magnews - s3. · pdf filefields and flux tubes in an mri magnet. ... report on ukmag seminar...

Magnews Autumn 2008 1

magnews

The international publication of the UK Magnetics Society

Autumn 2008

Magnews is published by the UK Magnetics Society, Grove Business Centre, Grove Technology Park, Wantage, Oxon OX12 9FA

[email protected], www.ukmagsoc.org

World’s Largest Magnet Project Powers Up

2 Magnews Autumn 2008

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Fields and flux tubes in an MRI Magnet


Contents FROM THE CHAIRMAN

The Editor accepts no responsbility or liability in any way whatsoever for statements made or opinions expressed in Magnews

From the Chairman 3UKMAG members news 4,5Company profile, new member COMSOL 4 Professor David Howe retires 5Welcome to new UKMAG members 5 World’s Largest Magnet Project Powers Up 6 International Electrotechnical Commission Committee TC68: 7

Magnetic Alloys & Steels, Progress in Magnetic Standards Report on UKMAG seminar Advanced Electrical Machines 8

through Materials, at TRW Conekt, Solihull, 15 Oct 08Daytona Magnetics seminar, 8/9 June 08 11 Creating Unconventional Metals 13Letter to the Editor 14High Temperature, Flexible Nanocomposite Electrically 15

Insulating CoatingsCorrosion Effects on Bonded Magnets in an Automotive 15

Environment 10th International Workshop on 1&2 Dimensional Magnetic 19

Measurement and Testing (1&2 DM) Advertising in Magnews 21 25 Years of the NdFeB Magnet Industry (continued from 22

summer 2008 Magnews) Student Bursary Scheme/Dennis Hadfield Memorial Prize 26UKMAG forthcoming seminars: 28

5 Nov 08, • CAD for Electromagnetic Devices, at Rolls-Royce plc, Derby19 Nov 08, • Permanent Magnets in Extreme Environments, at University of Birmingham9 Dec 08, 22nd Ewing Lecture: • Healthcare Biomagnetics: a New Age for Magnetic Therapy, and afternoon programme Frontiers of Medicine: New and Emerging Roles for Bio-magnetics, at The Royal Society, London4 Feb 09, • Noise in Electrical Machines, at Cardiff University19 Mar 09, • Advanced Functional Materials, at the National Physical Laboratory, Teddington2 April 09, • More Electric Aircraft, at University of Bristol

Dates for your Diary 30 UKMAG Management Committee 30

Front page graphic: one of the 1232 dipole magnets for the LHC being lowered down the delivery tunnel at CERN before installation in the collider ring, image copyright CERN - see page 6

Welcome to the autumn edition of Magnews. Well, what a momentous start we all had to this autumn! Potentially,

one of the most groundbreaking scientific programmes for decades started with a finger on a button and countless others crossed. At 8.30am on Wednesday, 10 September, the Large Hadron Collider began its search for, amongst many other things, the source of mass. I listened intently to the events unfold through the earphone of my little personal radio as I sat in a café at the side of the A299. The level of excitement and collective anticipation, scientists and radio presenters alike, rose and then…. jubilation! as the first packet of protons made it through the first stage of the collider. As the folk at CERN popped their champagne, I smiled and raised my mug of Little Chef tea to the future we are on the brink of discovering.

Although perhaps not quite as big as CERN’s, our autumn seminar season also started with a bang at TRW Conekt in Solihull on 15 October, with the Advanced Electrical Machines through Materials seminar. This event focused on the results of three years of research by a consortium of 16 industrial and academic partners. Each programme of work designed to further the boundaries of electrical machine performance, from high temperature conductor insulation to improving measurement techniques. I really enjoyed the seminar and I hope you enjoy reading the write up in this issue by Dr Hugh Stanbury who managed the overall project, see page 8.

We have three further seminars to see out 2008. The first, CAD for Electromagnetic Devices, takes place on 5 November at Rolls Royce in Derby. As it did in 2006, this seminar offers a strong technical programme as well as an exhibition of the latest CAD software and tools during the lunchtime networking break. A highlight of the seminar will be a keynote speech on Design Optimisation, by Professor Jan Sykulski of Southampton University.

The CAD seminar will be followed by Permanent Magnets in Extreme Environments at Birmingham University on 19 November. The environmental spectrum covered by the seminar is extreme in itself, ranging from undersea to outer space.

Our final event of 2008 is, of course, the 22nd Ewing Lecture. This year’s lecture will be held at The Royal Society in London on 9 December and will be presented by Professor Quentin Pankhurst. Professor Pankhurst is the Director of the Royal Institution’s Davy Faraday Research Laboratory and a leading light in the field of Biomagnetics. His topic for this year’s Ewing Lecture is Healthcare Biomagnetics: A New age for Magnet Therapy. To complement Professor Pankhurst’s evening lecture, we have a diverse afternoon programme - Frontiers of Medicine: New and Emerging Roles for Biomagnetics, the award of the Dennis Hadfield Memorial Prize, followed by our usual wine and buffet supper. Full details of this year’s Ewing Event can be found on page 29.

I hope you enjoy this edition of Magnews and I also hope that the glorious shades of autumn warm you against the impending chill of winter.

Chris Maddison, Cummins Generator Technologies


UKMAG Members’ News

Copy for Magnews Members are invited to send technical articles, conference reviews, details of workshops or training courses, or general news for inclusion in forthcoming issues of Magnews to the Editor, [email protected] (see page 21 for copy deadlines)

NPL is about to embark on an exciting new channel to support UK based technology business and we are seeking

your help to deliver the best service.

Listening to our customers, we understand that access to our knowledge and facilities is key to product development and business success. We are looking to maximise the facilities of the NPL site by developing an innovation centre that will support knowledge exchange from our facilities and people to you.

As a supporter of NPL, we hope that you will take a few minutes of your valuable time to assist us in shaping this service by completing a brief survey: NPL Innovation Centre - Concept and Survey, www.npl.co.uk.

NPL is one of the top three National Measurement Institutes in the world. As a national resource, our goal is to ensure that our capability is accessible and relevant.

Your participation is highly valued and we are looking forward to your views. We will keep in touch with this project as it develops.For further details contact Dr Sally Wilson, Commercial Director, National Physical Laboratory, www.npl.co.uk

An Innovation Centre for NPL

Company Profile - new UKMAG memberCOMSOL develops and markets 3D modelling software

called COMSOL Multiphysics. This software has been developed to provide scientists and engineers with an easy-to-use environment that enables them to simulate the behaviour of multiple physical phenomena including electromagnetics; from low frequency applications such as motors and generators through to RF and Optics.

A unique characteristic of COMSOL Multiphysics is its ability to handle unlimited Multiphysics couplings. This means that users can develop models for electromagnetic behaviour that can also include heat transfer, structural mechanics, fluid dynamics, acoustics and so on. All of these couplings are solved in a single, fully-coupled solution if necessary.

COMSOL Multiphysics can be fully integrated with other tools used in design and optimisation including SPICE circuit lists and geometry file imports from CAD and ECAD systems.

Typical applications include: motors, generators, inductors; HVDC; microwave and RF heating; plasma physics; waveguides and photonics.

COMSOL Multiphysics is an entirely ‘open’ system so that although it is provided with an array of ready-made physics applications, users are free to add to or modify any of the equations provided. Models also can be fully linked to MATLAB programs. This makes it a very powerful tool for researchers and for those who need to go beyond the standard applications traditionally supplied by commercial modelling software. This equation-driven mode means that not only can users build their own applications but they can also enter loads, boundary conditions and material properties as equations or test data.

COMSOL is a Swedish company with 12 offices in the US and Europe and distributorships throughout the world. With over 40,000 licenses worldwide COMSOL Multiphysics enjoys widespread use in engineering companies, research establishments and academia.For further information visit www.uk.comsol.com or contact Keith Howard, tel: +44 (0)1707 636 020 or [email protected]

UKMAG seminar papers UKMAG seminar papers are available to members free of charge; non-members may purchase sets of papers after the event has taken place. For further details contact: [email protected]

Student Bursary Scheme/Dennis Hadfield Memorial PrizeStudents from institutions who are members of the UK Magnetics Society, academic or industrial partners, are are eligible for a bursary to support their attendance at international conferences (see page 26 for further details)


UKMAG members news contd...

After working for around 40 years in academia, Professor David Howe has retired as Head of the Electrical Machines

and Drives Group at the University of Sheffield. His first appointment was at Brunel University in 1966, the year in which he married his wife, Kay. He then moved to Southampton, where he obtained his PhD for research into end-effects in large electrical machines. He continued to work on electromagnetic problems associated with turbogenerators after taking up a post at C A Parsons/NEI Ltd in Newcastle.

However, for the past 30 years or so he has been with the Electrical Machines and Drives Group in Sheffield, his home city. During this time, he has overseen significant developments in the Group’s research activities and facilities, its international standing and its size, the Group currently numbering around 80 personnel. At the same time, he helped launch two spin-out companies; Magnetic Systems Technology Ltd in 1993 and Magnomatics Ltd in 2006, as well as the Rolls-Royce University Technology Centre in Advanced Electrical Machines and Drives, of which he was the first Director.

Much of the success of the Electrical Machines and Drives Group has been based on the extraordinary advances which have occurred in permanent magnets over the past 25 years, and associated developments in permanent magnet machines and drives as well as in other engineering applications. In this regard, a significant aspect was the Group’s participation in the EC-funded Concerted European Action on Magnets (CEAM) initiative, which was launched in the mid-80’s in response to rapid developments which were being made in rare-earth magnets. This not only enabled the Group to collaborate with other electrical engineers throughout Europe, in both academia and industry, but also with eminent physists and material scientists. David and his colleagues at Sheffield continue to pioneer the development of new and improved design/analysis techniques as well as novel and challenging applications, which range from magnetic gears and CVT’s to tubular machines for free-piston energy converters and active vehicle suspension.

During his very distinguished career, David Howe has given many invited presentations at major international conferences, as well as numerous public lectures, including the UK Magnetics Society Ewing Lecture at The Royal Society in 1994, the Hague Memorial Lecture at the University of Glasgow in 2006, the Blumlein Memorial Lecture at the IET, Savoy Place, in 1997, and the prestige lecture at the British Association for the Advancement of Science meeting in Sheffield in 1996.

To date, he has authored/co-authored around 800 journal/conference papers, many of which are definitive in their field. In recognition of his contributions to advancing knowledge in electrical engineering, David was elected a Fellow of the Royal Academy of Engineering in 2003.

Around 150 friends and colleagues, both past and present, attended David’s retirement party at the Hilton Hotel in

Professor David Howe retires!Sheffield on Friday, 3 October. The guests enjoyed a pre-dinner reception and three-course meal, with musical entertainment

from Absolute Strings, followed by a disco and a very late bar! Guests came from far and wide, from both industry and academia, and included many of his former research students and research associates/fellows. The academics included many UK Magnetics Society members, including: Professor Mike Coey, Trinity College, Dublin; Professor Rex Harris, University of Birmingham; Professors Alan Jack and Barrie Mecrow, University of Newcastle; Professor Rod Smith, Imperial College, and Professor Phil Mellor,

University of Bristol, whilst industrialists who attended included John Taylor, SG Magnets; Jeff Coles, TRW Conekt; Dr Chris Riley, Magnet Applications; Dr David Manley, MachineWorks Ltd; Carl Maxwell, Goodrich, and Brian Simmers, Rolls-Royce.

During the party, David was presented with various gifts in appreciation of his work over so many years. However, in a short response he made it clear that, although his retirement marked the end of a chapter in his life, he would continue his association with the Electrical Machines and Drives Group in his new capacity as Emeritus Professor, and that he was particularly looking forward to working with colleagues at Magnomatics Ltd. He also emphasised that the achievements of the Electrical Machines and Drives Group were very much the result of a team effort and praised the very important role which the Group secretaries, Sara and Fiona, had played in its success.

In summary, the event was a great celebration, which provided an opportunity for many happy reunions, not least of UK Magnetics Society members.

Reminiscing - David Howe, Mrs Vera Harris, Rex Harris and Hywel Davies

Welcome to new UKMAG membersCOMSOL LtdDyson Technology Centre Magnomatics LtdMetrolab Instruments SA, SwitzerlandElectronica Products LtdSchlumberger Oilfield UK plcMuirhead Aerospace Ltd


To much fanfare and after more than a decade of planning and construction,

the Large Hadron Collider at CERN, the European Organisation for Nuclear Research circulated its first protons around its 27km circumference, 100m underneath the border of France and Switzerland, on 10 September. Even though just a few days later a teething problem for the newest particle accelerator meant that the machine had to be shutdown for at least two months, to realise such a massive engineering project is a huge achievement.

The goal of the project is to answer questions – and no doubt to raise some more, stimulating new theories – about our understanding of fundamental particle physics:

to directly detect the • Higgs boson, the particle that mediates mass

to look for evidence of particles • relating to Supersymmetry theory that could help in the quest to unify the four fundamental forces (electromagnetic, strong, weak and gravity)

supersymmetric particles could also help • to explain theories about dark matter

the LHC will also help research into • antimatter and why our universe is made only from matter.

The LHC aims to do this by colliding two beams of protons accelerated to close to the speed of light and thus to energies not previously tested in particle accelerators, re-creating energy densities and temperature conditions that were

World’s Largest Magnet Project Powers Uppresent shortly after the big bang. The two beams are accelerated by a succession of accelerator rings - of which the LHC is the last one - and travel in opposite directions around two parallel ultrahigh vacuum tubes before being brought to a collision in four intersection points around the ring where the detector experiments are located and will trace the collision products with their state of the art sensor technology.

Crucial to the operation of the LHC is manipulation of the charged particles by magnetic fields. Some 1232 dipole magnets

keep the beams in a circular path around the ring whilst 392 quadrupole magnets focus the beams to increase the chances of collisions. In addition there are sextupoles and octupoles, which contribute to the optimisation of the particles’ trajectory not to mention the massive magnets in the detectors to guide particles resulting from the collisions to help to characterise them.

These are not permanent magnets, but superconducting magnets providing intense fields. The 1232 dipole magnets which line the 27km ring are cooled to 1.9K (cooler than space), their NbTi cables energised with currents of 11,700A to generate fields of 8.3T – important as the maximum energy of the LHC is proportional to the strength of the dipole field. Each dipole magnet is 15m long, weighs 35 tonnes as it contains so much iron and all 1232 together will have about 11GJ of energy stored in them. The cryogenic system for the dipoles constitutes the largest refrigeration project in the world, requiring 120 tonnes of liquid helium and a refrigeration capacity of over 150kW.

Rather than what one might imagine, just two protons coming together and colliding, there will be of the order of 100 billion protons in well-defined bunches circulating the LHC in a beam nominally a few centimetres long and 1mm wide, and confined to 16 microns at the intersection points. When the two bunches of protons come together there will be about 20 collisions between the 200 billion protons involved as they are of course electrically repelled by each other. However, as the particles are travelling close to the speed of light the bunches will circulate the 27km ring over 11,000 times per second such that the LHC generates up to 600 million particle collisions per second. By squeezing as many particles into as small a cross-sectional area as possible the luminosity of the machine is greater than any previous particle accelerator.

The total energy in each beam will be about 350MJ –about as energetic as a 400 tonne train travelling at 150km/h – enough energy to melt 500kg of copper! Clearly this amount of energy could be catastrophic for the machine should the beam become unstable during operation, and hence beam loss sensors detect instabilities and a set of magnets are able to divert the beam out of the ring and into a special beam stop block which will absorb the energy.

Once collisions are taking place, it is then the job of the gigantic detectors to count, track and characterise the particles from the collision. These are also extremely complex machines with the two principal ones, ATLAS and CMS, weighing in at 7,000 and 12,500 tonnes. These are the two ‘general purpose’ detectors furnished with many layers of different types of sub-detectors to identify the secondary particles by measuring their position in space, their charges, speed, mass and energy. There

Cross section of an LHC dipole magnet, image copyright CERN

Engineers carry out tests on the completed magnet ring, image copyright CERN


are another four detectors for more specialised measurements looking at answering specific particle physics questions.

The LHC project then becomes an exercise in statistics and computer power. Although the particle collision rate at LHC will be very high, the production rate of the more rare particles (those associated with supersymmetry theory, including the Higgs boson) will be very small and will be masked by the high proportion of other already well-known particle flavours that will be expected. The LHC experiments represent about 150 million sensors delivering data 40 million times per second. The data flow from all four main experiments will be about 700MB/s, equating to 15 million GB (15 Peta Bytes) for a whole year’s worth of data. LHC project physicists only expect to have enough statistics to make any meaningful conclusions to their experiments after a whole year of data taking. Patience is a pre-requisite of being a high-energy particle physicist.

In September this year, IEC TC68, the principal technical committee for the preparation of standards for magnetic

alloys and steels, held three working group meetings in the United Kingdom to progress the development of product specifications and measurement procedures for these materials.These followed on from the Plenary Meeting which was held in Shanghai last year and was reported in the Winter 2007 issue of Magnews. The meetings were attended by experts from Europe, Japan, Korea and China and were timetabled to match up with the 10th International Workshop being held in Cardiff University on 1&2 Dimensional Magnetic Measurement and Testing.

The Joint Working Group, which is responsible for the magnetic material specifications, met at the offices of the British Standards Institution in London under the convenorship of Bernard Creton.The new standard for grain oriented silicon steels, IEC 60404-8-7, has now been published. This covers the new low power loss, high permeability grain oriented grades which are achieved through domain refinement on the final continuous process line.

Further progress is now being made on the IEC document 60404-8-10 which sets out the specifications for relay steels following the round up of international comments received on the draft text. This will soon be available as a final voting document for international acceptance.

Working Group 2, which is responsible for the preparation of the magnetic measurement standards of the IEC, met at the Wolfson Centre in Cardiff University under the convenorship of Dr Geoff Hilton. Again, there was a very strong international attendance at this meeting and this enabled very detailed and informed discussions to take place on the standards documents under consideration.

At present, the IEC does not publish a measurement standard for the very important area of low permeability materials. This is now being addressed by a new work proposal which is based on the current British Standard on this topic. The project received international approval and a document was prepared as a committee draft which is destined for IEC 60404-15.

WG2 is preparing a Technical Report on methods of measurement of magnetostriction. It has now progressed well in the drafting stage and it will provide a full and comprehensive

survey of the methods of measurement of the magnetostriction of electrical steels especially where applied stresses have a critical influence on this parameter. The working group is also bringing together experts to assess the measurement of magnetic shielding by sheet materials. This is particularly relevant in the technology of MRI scanners and international comparisons are being set up to develop a consensus of opinion on the materials used in industrial magnetic shielding enclosures.

The international membership of the TC68 working groups provides excellent opportunities to carry out comparison measurements between organisations in order to develop the technology, and improve the accuracy, of a particular measurement before it is taken to a proposal for a measurement standard. Importantly, two comparative exercises are taking place at present – a round robin test for vibrating sample magnetometers and a permanent magnet round robin using permeameter and pulse field magnetometer methods.

In the technical area of magnetically hard materials Working Group 5, with Dr Hitoshi Yamamoto as convenor, is developing two technical reports to describe the magnetisation behaviour of permanent magnets and the stability of rare earth sintered magnets at elevated temperature. These documents have attracted considerable interest since the Shanghai meeting and will provide extremely valuable information to the permanent magnet manufacturers especially where the components are being used in harsh environments.

The international interest in magnetic specifications is very strong with over 40 experts attending these meetings and we are grateful to these experts and their organisations for their continuing support of this work.

I should also like to express my thanks to Mr Peter Slot of the British Standards Institution and Prof David Jiles of the Wolfson Centre for Magnetics for their welcome and support in hosting these meetings.For more information please contact Dr Hugh Stanbury, [email protected]

International Electrotechnical Commission Technical Committee TC68: Magnetic Alloys and Steels, Progress in Magnetics Standards Dr Hugh Stanbury, Chairman IEC TC68, Wolfson Centre for Magnetics, Cardiff University

All told, with the super-cooled magnets and the detectors, the power consumption of the Large Hadron Collider when operating throughout the year will be around 120MW, whilst the CERN site as a whole will require 230MW, equivalent to roughly a quarter of the capacity of a nuclear power station. Its yearly consumption is estimated to be 800,000 MWh, costing approximately 19 million Euros. Although the project leaders have expressed their obvious disappointment at the set-back with the quenching of a section of the magnets caused by an electrical fault, meaning that they have to be warmed up, the fault repaired and cooled back down again – a process that takes many weeks, once the LHC powers up once again at the start of 2009, all physicists will be hoping for many years of smooth fault-free operation that in time will give data that proves the theoreticians postulations of the last 20 years and allows them to delve deeper into how the physical universe works.


The seminar was hosted by TRW Conekt at their Solihull Technical

Centre and with an attendance of over 40 delegates there was a wide range of interest in the day’s nine presentations.The aim of the seminar was to disseminate the results of the researches undertaken through the Advanced Electric Machines through Materials Project (The Magnetics Project) which was co-funded by the Technology Strategy Board and led by Powdermatrix.

In his welcome to the delegates and introduction to the project Dr Hugh Stanbury explained that the project was launched in 2005 by PowdermatriX in response to a call by the DTI (now the Technology Strategy Board) Technology Programme to improve fuel efficiency and to reduce CO2 emissions. This three year, £2.4M project involved 16 partners from the UK Magnetics Industry to develop improved magnetic materials, processing technologies, measurement facilities and computer modelling capability for electric machines. The project focused on technologies being developed for more efficient power systems, particularly for the aerospace and automotive industries and was organised through five Work Packages to cover all aspects of the researches:

WP1–Magnetic materials test and measurement under operating conditionsWP2a–Low temperature (250oC) high strength soft magnetic materials for rotating machinesWP2b – High temperature (500oC) high strength soft magnetic materials for high speed rotating machinesWP3 – Modelling toolsWP4–Anisotropic NdFeB powder compression bonding, magnetisation and protectionWP5–High temperature (up to 500oC) insulation for magnet wire.

The project was specifically structured to establish collaboration through the magnetics supply chain and to optimise and extend the range of existing magnetic materials as well as developing new propriety products.

Philip McGoldrick, Goodrich Power Systems, set the scene for this work in his

presentation entitled Meeting the Material Challenges for the More Electric Engine and explained that there are three key domains of advanced materials that can

make a difference to electric machines:

the primary active materials (copper, • electrical steels and permanent magnetsthe ancillary secondary materials • (sleeves, liners, enamels, insulators etc)the manufacturing process control.•

Philip explained that a significant improvement in the overall electrical machine cannot be achieved through the improvement in performance of a single domain but that a “multi-strand” approach must be adopted. In particular, he illustrated this principle with a description of developments of the aircraft fuel pump where the unit becomes reduced in size and is subjected to a more stressed environment.

This theme was then taken up by Dr John Cullen of Rolls-Royce in his presentation on Meeting the Material Challenges of the More Electric Engine. John proposed that with novel designs and high strength magnetic materials weight savings of 15% could be achieved on engines of the future if they could be located within the gas turbine and so reduce the weight penalty of drive shafts, gearboxes. A key part of this concept will be the development of the integrated starter generator, co-axially inside the engine core.

The challenges that this presents to the magnetic material are immense. Iron-cobalt cores, which are the traditional choice of the aircraft generator manufacturers, have excellent soft magnetic properties but in order for

them to operate under extreme rotational forces and at high temperature a reduction in the magnetic properties is inevitable if the mechanical properties

at elevated temperature are to be improved.

The laboratories at Qinetiq have devised a fabrication route for producing hoop reinforced FeCo rings using a hybrid foil wire technique. The process is based on co-winding FeCo wire and SiC fibre into double spirals of alternate wire and fibre, which are interleaved with FeCo foil. This structure is then encapsulated, evacuated and hot isostatically pressed to consolidate it into a fully dense composite material, which could then be machined into the rotor of the electrical

generator. Further developments have produced a fibre reinforced foil which can form the FeCo laminated teeth of this composite rotor. The laminated pole pieces are then diffusion bonded to the fibre reinforced rotor hub. John then described briefly the development of a high temperature insulation for magnet wire which was undertaken by Teesside University and was described later in the seminar by Professor Simon Hodgson.

In the next presentation, Measurement of the Properties of Magnetic Materials –Underpinning the Project Needs and Enhancing the UK Capability, Dr Michael Hall of NPL described the measurement work which was carried out under Work Package 1 at NPL, the Wolfson Centre at Cardiff University and TRW Conekt. Michael explained that Work Package 1 provided the magnetic measurement and testing support to the partners in the project. These covered:

the measurement of the magnetic • properties under stress (in particular the fibre reinforced composite FeCo material developed by Qinetiq)the measurement of the properties of the • soft magnetic cores developed by CERAMthe behaviour of materials selected for • the project under magnetic excitation with flux waveforms (non-sinusoidal) and frequencies to duplicate those experienced by actual machines, eg automobile power steering motorspermanent magnets subjected to differing • magnetising and demagnetising conditions

UKMAG seminar Advanced Electric Machines through Materials (The Magnetics Project), 15 October 2008, at TRW Conekt, Solihull


the construction of a data base to cover • all the measurements performed for the project.

In meeting these objectives, new measurement systems have been devised as for example in the NPL dc permeameter where the dc magnetic properties of silicon steels and the high strength Rotelloy 8 have been measured under tensile stresses in 50MPa steps up to the point of fracture. Michael illustrated his talk with hysteresis loops taken at up to 650 MPa for Rotelloy 8 which had been annealed at 715ºC and 880ºC. The material showed an improvement in the dc properties at 50 MPa and thereafter a deterioration in the properties. The stress permeameter was designed, especially, for measurements on the new fibre strengthened FeCo strip material. However, closed circuit permeametry does have limitations when magnetic properties are being measured at extremes of stress and temperature and, in concluding his talk, Michael outlined the new open circuit permeameter developments at NPL which, it is expected, will accommodate these measurements.

Dr Alex Michaelides of Vector Fields described the work carried out in Work Package 3 in his presentation Advanced Multi-Physics Modelling of Electric Machines. The activities of WP3 were shared by the software modelling companies of Vector Fields and Motor Design Ltd.

The main objective for Vector Fields was to develop a new generation of software tools that meet the future needs of electrical machines designers, by establishing relationships with Prime Technology Companies, who are partners in the project, and to work with their design engineers, the main goals being:

the development of permanent magnet • magnetisation and demagnetisation solvers in OPERA-2d and OPERA-3d to allow designers to model accurately the performance of permanent magnet machines, accounting for operation under increased temperatures and de-magnetising armature currentsthe development of a new Hysteresis • solver in OPERA. This development would solve the notoriously difficult problem of hysteresis loss evaluation in electrical machines, while also quantifying drag force problems in actuators and machines that employ permanent magnetsin collaboration with partner companies • in the Magnetics Project, the expansion of the developments of Electric Machines Design Environments in order to accelerate the design of electrical machines, with a special focus on non-standard machine types such as axial flux geometries.

These activities built on the interchange of design and performance specifications between the electric generator constructors and the software developers throughout the project. For example, the second goal received significant support from TRW who manufacture electrically powered steering systems, requiring electric motors which meet extremely demanding specifications. One of these is that it should take very little torque to rotate the motors’ rotors when the coils are not energised (this torque is referred to as ‘drag-torque’). As drag-torque is related to the hysteresis loss in the stator lamination material, when the rotor magnets move past the stator teeth, a design tool that would include the ability to simulate hysteresis would be particularly useful for the company. Harvey Smith of TRW Conekt described the motor builder’s perspective of this in his presentation later in the day.

The third goal was supported by Cummins Generator Technologies who have long experience in the manufacture of conventional electrical machines. The company’s standardised products share common features over the product range and, in order to design, model and analyse electrical machines using Vector Fields OPERA, significant user-interaction is required which can be considerably reduced by creating variations to the standardised products simply by changing a set of parameters defining the model geometries. This user-software designer interaction was especially important in the 3D modelling of the TORUS axial flux machine.

In parallel with this, the work of Motor Design Ltd was to develop a method to expand the electric motor thermal models automatically constructed in the Motor-CAD software to include the surrounding system within which they are built. The surrounding system may be quite complex for a motor embedded deep within apparatus such as aircraft turbines. Thermal analysis of such machines is critical as very high temperatures are expected and the high temperature applications within this project are typical of such systems and so improved thermal analysis methods were seen to be important.

The two modelling partners worked closely throughout the project and established improved data links between

the OPERA, MotorCAD and SPEED software (from Glasgow University). This enabled the electric machine designer to make more extensive design calculations easier and faster.

Dr Chris Riley of Magnet Applications Ltd described the work undertaken in Work Package 4 on the corrosion effects on bonded magnets in an automotive environment in his presentation, Corrosion Effects on Bonded Magnets in an Automotive Environment. Polymer bonded magnets are used in brushless dc motors for electric water coolant pumps in the “more electric” or hybrid electric vehicles. The pump, which is built by Pierburg Pump Technology Ltd, is designed for use in either de-ionised water, as in fuel cell applications, or in ethylene-glycol/water mixtures for automotive cooling systems where the temperature will reach 90ºC. Critically, the pump is designed so that the pumped liquid flows

around the permanent magnet rotor as well as the impeller. The magnet is normally protected from the liquid by being encased in a stainless steel can but this, in effect, increases the air gap in the motor and can reduce the performance of the motor. A solution would be to protect the magnet against the corrosive effects of the liquid.

Two approaches to this problem were taken:

a study of the effectiveness of sol-gel • coatings in protecting the magneta fundamental examination of the • corrosion mechanisms in NdFeB magnets undertaken by Birmingham University.

The corrosion testing programme covered a very wide range of accelerated environmental tests to duplicate the operating conditions of the motors with variations of epoxy and sol-gel magnet coatings in immersion tests. Essentially, the coatings were not found to offer much protection against these harsh

Speakers left: Hugh Stanbury, Alex Michaelides,Simon Hodgson, Chris Riley, John Cullen, Michael Hall, Philip McGoldrick, Nick Adkins, Harvey Smith


much protection against these harsh environmental conditions with, for example, the BH max product reducing by as much as 10% and the coercive field strength by as much as 25% for sol-gel coatings in de-ionised water at 90ºC.

The Birmingham University investigation into these deteriorations in magnetic properties concluded that:

the decrease in coercive field strength is due • to the absorption of hydrogen which can diffuse rapidly from the aqueous corrosion of the MagneQuench NdFeB flakesPTFE bonding provides the best • protection against antifreeze, although there is some initial deterioration the properties which then stabilise.

Chris concluded that although coatings can give some protection against surface corrosion of the magnets, there will still be a high deterioration of the magnetic properties. The ingress of hydrogen has been shown to be associated with this loss. Further work is planned to examine alternative sol-gel formulations and resins.

A principal consideration in the development of electrical machines required to operate at higher temperatures is that of the electrical insulation of the conducting wires. This was taken up by Prof Simon Hodgson of Teesside University in his presentation on High-Temperature Flexible Nanocomposite Electrically Insulating Coatings. Insulated wire needs to be produced in volume, and at reasonable cost, to be compatible with machine designs (mechanical strength, flexibility and high dielectric strength) and to be able to withstand the mechanisms of winding and assembly. The aims of a high temperature wire are to withstand temperatures of greater than 450ºC in the long term and to have high electrical resistance under these conditions. Commercially available polyimide insulated wire has an upper, long term temperature limit of 250ºC. Other alternatives, such as inorganic coatings (enamels or sol-gel silica), can be too brittle to survive assembly and may become conducting at high temperature.

The insulating coating which has been developed at Teesside University consists of a multi-layered structure of graded composition. The Teesside approach has considered the design requirements at different stages in the manufacture and service life of these machines. The requirement of mechanical flexibility is critical at the winding and assembly stage, but when the winding has been assembled the service requirement of high temperature dielectric strength is the critical parameter. The coating was therefore multi-layered and required that copper wire is nickel plated to assist the coating adhesion.

The insulation is based on hybrid organic-inorganic nano-composites which can be engineered to allow the functionality to be modified at different stages in the life cycle of the material. The composite is comprised of a base layer and an outer layer. The base layer has the lowest organic content to minimise shrinkage and outgassing, whereas the top layer has increased organic content to provide the required flexibility. The composite suspension includes a ceramic filler of vermiculite particles in platelet form. This means that the design constraints can be relaxed by consideration of the “stage of life” where the organic functionality can be temporary. On heating, the organics are burnt out and the inorganic bonding is formed to provide the insulated state for service – the photographs of twisted wires do show exceptional flexibility and lack of cracking for this high temperature/high dielectric strength specification. The University has a pilot plant facility for producing 100 m lengths of insulated wire and through optimisation of the process an insulated wire was produced which achieved all the aims of the project:

exceptional flexibility without fracturing • or peeling off the wiregreater than 1000V breakdown voltage• low current leakage• operating temperature of greater than • 450ºC over the long term.

A patent application has been filed for this new process and future work will see this material being assessed further by the aerospace electrical machine industry.

Dr Nick Adkins of CERAM described the project work on A Novel Soft Magnetic Composite Material where he considered the ideal properties of a soft magnetic composite as having the highest magnetic material density as possible whilst ensuring that the metallic cores of the powders remain electrically isolated from each other. In the CERAM process a nano-scale magnetite was used to coat the larger metal powders which were then pressed and sintered. Since magnetite is an insulator and is also ferromagnetic it was expected that it would also provide a contribution to the magnetic permeability of the compact. The conventional method of providing a high electrical resistivity is to form an insulating coating by wet coating on the powder particles before they are pressed and sintered together to form a monolithic solid of high density.

However, this process was found to be unreliable so a method of fluidising the iron powder by rotation in a flow of CO2 gas at a temperature of 500ºC or 550ºC was developed. This produces a magnetite (Fe3O4) coating on the iron

particles through the action of CO2 on the Fe powder. The fully dense blocks were then formed by hot isostatic pressing (HIPing) at 1100ºC for two hours. In order to accommodate magnetic measurements on these compacts standard test toroids were produced through design of the HIP container and the magnetic and electrical properties of these test specimens were measured at the Wolfson Centre, Cardiff University. The measurements showed that the electrical resistivity of the test specimens was unexpectedly low and the specific total loss (power loss) was very high when compared to commercial soft magnetic composites. However, on examination of the microstructure, the reason for this poor performance could be traced to small breaks in the coating which would create conductive paths between the particles and thus reduce the bulk resistivity of the compact with resulting increases in the eddy current loss.

CERAM then undertook very lengthy investigations into optimising the coating and HIPing conditions and it was determined that coating at a lower temperature for a shorter period produced much improved magnetic properties. The best material produced through this process gave a dc magnetic flux density of 1.443 T at 8 kA/m, which is better than commercially available material, ac permeability was 5-–6 times higher than commercial material although the ac loss was poorer. It was also determined that a further heat treatment after the final process was not necessary as this was found to have a deleterious effect on the magnetic properties.

Nick concluded that following the optimisation of coating time and temperature, 15 mins at 475ºC, further work could lead to the investigation of higher purity iron powder and the scaling up of the coating equipment.

The final presentation of the day was given by Harvey Smith of TRW Conekt who described the work carried out in Work Package 2a on Drag Torque vs Material Properties in TRW Steering Motors. Harvey started his talk by stating that automotive power steering systems driven by electric motors are more efficient and “greener” than conventional hydraulic systems. However, in order to give acceptable performance the “drag torque” of the system must be minimised. This is the torque set up by the motor in opposition to its motion when the motor is not energised and it is being driven by the self-centring action of the road wheels so that the drag torque contributes to the overall friction of the system. The selection of the lamination material in the motor is critical in minimising the drag torque so the Work Package set up

Advanced Machines through Materials seminar contd...


an assessment of electrical steel lamination materials against drag torque performance.

A selection of non-oriented silicon steels was supplied by Cogent and the assessments were conducted by TRW. Since the drag torque effect takes place at a very low rate of change of flux the assessments were made against the dc magnetic properties of the lamination materials, particularly for those materials of low hysteresis. In addition, a material of high coercivity was selected for comparison purposes and the dc measurements were carried out on the TRW dc permeameter on toroidally wound ring samples of laminations.

Drag torque measurements were performed on laminations prepared through wire erosion (and annealing where required for semi-processed materials) and tested on a test rig where the stator laminations are embedded in a non-magnetic housing. The torque was measured by a torque transducer as the rotor was rotated at 1–2 rpm under a magnetic excitation to match normal operating conditions.

Analysis showed that the hysteresis loss was closely related to the drag torque and coercivity, in particular, showed a clear linear relationship. This link was also supported by software modelling undertaken the partners in Work Package 3. Therefore, material selection on the basis of coercivity, which can be measured routinely, will be a key part of material selection for power steering motors.

The UK Magnetics Society and Powdermatrix would like to thank the speakers, the organisers of the meeting and TRW Conekt for kindly hosting the seminar. It was an ideal opportunity to disseminate the results of the Magnetics Project and there was considerable interest in the presentations, as shown by the keen questioning from the delegates after each presentation. The excellent buffet lunch also presented plenty of opportunities for the delegates to network.

Acknowledgement:This project is co-funded by the Technology Strategy Board’s Collaborative Research and Development programme, following an open competition. The Technology Strategy Board is an executive body established by the Government to drive innovation. It promotes and invests in research, development and the exploitation of science, technology and new ideas for the benefit of business - increasing sustainable economic growth in the UK and improving quality of life.

Dr Hugh Stanbury, Powdermatrix, [email protected]

I had met Karl Strnat 30 years ago just after he had made his far-reaching

discoveries of new permanent magnet materials (SmCo, both 1-5 and 2-17), so it was of considerable interest to read the papers presented which included several by his son Reinhold Strnat, and others at Dayton University. A friend of mine, Stan Trout, who helped organise the conference, kindly provided me with copies of the papers so I have written the following notes on them.

Magnetic Testing and Characterisation of Permanent Magnets and Magnetically Soft Materials, Reinhold M W Strnat, Magnetic Instrumentation Inc/KJS Associates: Compares methods of magnetic measurements, hysteresis graphs using ring sample, Epstein frame or with electromagnet. Single sheet tester, coercimeter solenoid for hci. electromagnet/yoke.Magnetising & Calibrating Permanent Magnets, Reinhold M W Strnat, Magnetic Instrumentation Inc/KJS Associates: Magnetisation before or after assembly. Calibrating motors and generators or loudspeakers etc. Capacitor discharge magnetiser.Researches for New Permanent Magnetic Materials with High Performance, Christina Chen and Sam Liu, University of Dayton Magnetics Laboratory: Covered the development of nano-composite magnets over the last 20 years including the deposition of alpha iron or mixtures of iron and cobalt on to NeFeB. Other possible new magnet alloys suggested are Dy or DyAl, but are speculative.Basics of Magnetism, Stan Trout, Spontaneous Materials: Michael Faraday described the first electric motors and was asked by a politician what good they were and replied “At present I do not know, but one day you will be able to tax them”. He covered magnetic poles, the use of iron filings to show the magnetic field lines, magnetic paper, different materials (soft, easy to change - ie for recording, hard to change - ie permanent magnets). Also hysterysis effects, units and formulae.Circuit Design Basics, Stan Trout, Spontaneous Materials: Formulae for magnetic circuit design.Mountain Pass Mine Update, Bob Noll, Sales Manager, Chevron Mining Inc: Has mines in five states for coal, rock etc. The Mountain Pass Mine in California is 50 miles south of Las Vegas and is the only developed source of rare earths in the Western world. The mine was last operated in 2002 but has recently

restarted separation. China produces over 95% of rare earths and consumes over 50%, output has increased by 28% a year since 2002. Global demand forecast to increase by 9% a year through 2012. Supply shortfalls predicted by 2010 as China restricts production. Magnets are one of four growth markets within the auto industry. Mountain Pass Mines bastnasite with approx 8.5% RE Oxide containing 12% Nd and 4% Pr. The mine can produce high purity products. It is proposed to reopen operations, first (from 2007) by processing existing stock piles to produce didymium for the magnet industry. Then (2009) by processing bastnasite from the stockpile. Finally by a full restart (2012) with new milling and separation facilities.

Rare Earth Resources, Jim Herchenroeder, Magnequench: The Neo Material Technologies Company, headquartered in Toronto, Canada, has two divisions: Magnequench (magnetic powder) and AMR (performance materials). Customers include Daido, Epson, Panasonic-Matsushita, Neomax/Sumitomo/Hitachi and others for non-magnet applications. The MQI Division based in Tianjin, China, has four alloy furnaces and 10 jet casters producing 3,850 tonnes/annum. The MQI Division based in Korat, Thailand, has two jet casters producing 770 tonnes/annum (two more are under construction).

Global demand for REs for magnets was 22,000 tonnes in 2006 and estimated at 45-50,000 tonnes for 2012, but mining quotas in 2007 caused prices to double. Also China increased export tax from 10% to 15% and 17% VAT rebate eliminated.

Rumoured further reduction in export quotas of 10-20% in second half of 2008. New RE suppliers are expected – Mountain Pass USA and Lynas Corporation, Mount Weld, Australia (21,000 tonnes by 2010). Other possibilities are in Russia, India, Australia and Canada – total possible output by 2012 is 45-60,000 tonnes but a significant shortfall in Dy and Tb output is expected (only 4.5% of Nd/Pr output); high temperature magnets need 25% Nd and 5% Dy ie 20% of Nd (See Comments at end)

Soft Magnetic Materials (Powder Cores) Bill Glass, Senior Applications Engineer, Magnetics (A Division of Spang & Co): Powered core technology is described and compared with ferrite powders, iron powders, Ni powders, iron/silicon.

Dayton Magnetics Seminar held 8-9 June 2008, at the University of Dayton


Ferrite Permanent Magnet Materials & Applications, Tony Morcos, Energy Conversion Systems: The paper commenced with a comparison of Neo, SmCo and Ferrite performance which offers lowest cost and has advantages of being not electrically conductive and non-corrosive. Also Lanthanum-Cobalt additives increase performance (Grades 9 & 11). Brushed and brushless DC motor examples are given, also loudspeakers with ferrite magnets.

Alnico Magnets: Over 80 Years of High Performance, Ed Richardson, Thomas & Skinner: Alni magnets were first developed in Japan and were followed by Alnico in 1933. Most of the alloy is iron but with a small amount of copper and titanium in some grades. GE used it in radio speakers. Alnico is very stable, allowing constant flux density over a wide temperature range and is corrosion resistant but brittle. Today, they are used in aerospace sensors and relays, some motors and hysterysis clutches, guitar pickups, radar, guidance systems and hearing aids. Most exports go to China, Japan and the UK.

Sm-Co Permanent Magnets and their Applications, Jinfang Liu, Electron Energy Corporation: The paper lists 1-5 and 2-17 grades including temperature compensated grades. The 2-17 magnets include high energy grades and high temperature magnets.

Magnet properties are given and show a wide range of capabilities, eg operating temperatures up to 550oC. Applications include accelerometers and gyroscopes, motors and generators, magnetic bearings and couplings. Hall Effect devices and travelling wave tubes.

Neodymium Iron Boron, Proliferation of Application and Manufacturing, Shuk Rashidi, Tridus International: Strip casting is now generally used, typically 3mm x 2mm thick which allows a fast cooling rate and closer control of particle size.

Application: Use of flywheel energy storage to provide power supply when needed.

Global sales of PMs expected to grow to $11 billion by 2010 ($7.9 billion in 2007)

Sales of Neo magnets expected to be $6.1 billion in 2010 ($4.34 billion in 2007)

Bonded Magnets, Steve Constantinides, Director of Technology, Arnold Magnetic Technologies: Arnold has manufactured magnets since 1939 and bonded magnets since 1992 following the acquisition of Plastiform from 3M.

There are now three facilities: Flaxmag Industries in Marietta, Ohio; Plastiform in Norfolk, Nebraska; and Bonded Magnet Group of Arnold Magnetics in Shenshen, China.

A wide range of bonded magnets are manufactured from Alnico, SmCo, NdFeB, Ferrite and Hybrids in injection moulded, compression moulded, flexible and rigid extruded forms. Performance and prices of bonded magnets are given, eg less than $2/lb for bonded ferrite to over $60/lb for bonded anisotropic Neo.

Compression bonded magnets use epoxy as the binder whereas extruded magnets use polyethylene and injection moulded use polyamide (nylon) or PPS.

Examples of magnetic orientations were given used in motors, couplings, loudspeakers, etc. Different forms of jet casting of Neo powders are compared.

Relative system cost comparison for a motor shows sintered Neo offers the lowest overall cost, sintered ferrite is 10% higher cost, sintered SmCo is 30% extra, injection moulded ferrite is 60% more, compression bonded Neo is 90% extra, injection moulded SmCo double the cost and injection moulded Neo 2.5 x the cost of sintered Neo.

Future of Magnets, Bhanu Chelluri, IAP Research, Inc: Described motor applications using insulated iron particles to obtain 3D designs, with embedded windings. A technique called Dynamic Magnetic Compaction, DMC, giving higher density with minimum use of binders. A comparison with Magnequench shows higher Br, Hc and BHmax. Magnets are embedded into the field assembly with a precise diameter. High strength rotors failed at 48,184 rpm (cf Magnequench at 24,000 rpm). SMC powdered iron was also shown with windings on individual teeth or with windings embedded into SMC pressed cores, achieving a uniform density of 7.5g/cc and improved thermal management due to the conduction of heat to the structure. Improved reliability and lower cost are also claimed.

Finite Element Analysis of Permanent Magnet Applications, Yuriy Zhilichev, Vector Fields, Inc: Describes the FEA technique using triangulation with a regular or irregular mesh with linear or quadratics elements to improve accuracy. Examples are given including the calculation of cogging torque ripple and demagnetisation effects at elevated temperature and stall conditions.

New Applications, Dr James Bell,

Magnet Applications: Magnet Applications has manufacturing plants in Berkhamsted, UK, and DuBois, PA, USA, and a sales office in Philadelphia PA. The company was acquired in April 2008 by Bunting Magnetics who manufacture magnetic conveyors, magnetic separators, flexible magnets, PM holding assemblies, etc.

The presentation listed present applications: automotive motors and sensors, industrial brushless DC motors, disc drive motors and actuators, aerospace and military, medical (MRI, surgical tools, pacemakers).

The future is expected to include small wind turbines (Air-X), the largest selling unit in the USA (15-20,000 per annum) which use about 3 tonnes of magnets per annum. Also midsize wind turbines, eg Skystream in 2007, 1.8kW costing $10,000 which uses an alternator with Neo magnets (3.2 kg/unit). Large size wind generators, eg Clipper 2.6 MW costing $4 million. Each unit has 4 PM generators. Estimated that 37,000 MW of new installations in 2020 which could require magnets of 10,000 to 40,000 tonnes/year. Note: This assumes the use of PM generators. Another application is in hybrid vehicles, eg Toyota and Honda use PM motors. By 2020, GM expects 80% of production to be hybrids. Magnet production would be 60,000 tonnes.

Estimated total production from 2007 to 2020:Ferrites: 725,000 to 1,210,000 tonnesNeo: 63,000 to 120,000 tonnes

Conclusion: Shortage of Neo will increase prices.

Comment: Peter Campbell writes a column in Magnetics Business & Technology and covered the Cost Benefit of Additives for NdFeB in the August/September 2008 edition. He concludes that motors for power steering and hybrid electric cars that need to operate up to 200oC need Dy additions. Even at the present $155/kg, Dy is justified.

2 wt% cobalt addition is also justified at its current cost of $95/kg (cobalt is a byproduct of nickel mining so further investment in the Congo is expected to bring cobalt down to $25/kg by 2015). Even so, 2% wt of cobalt is considered to be the optimum amount for sintered Neo. For bonded Neo using melt spun powder the optimum amount is higher (4wt%) as this increases flux by 2% for a premium of $1/kg.John G W West

Dayton Magnetics seminar 2008 contd...


The semiconductor silicon and the ferromagnet iron are the basis for

much of mankind’s technology, used in everything from computers to electric motors. In the 21 August 2008 issue of the journal Nature, an international group of scientists, including academic and industrial researchers from the London Centre for Nanotechnology (UK), USA and Lesotho, report that they have combined these elements with a small amount of another common metal, manganese, to create a new material which is neither a magnet nor an ordinary semiconductor. The paper goes on to show how a small magnetic field can be used to switch ordinary semiconducting behaviour (such as that seen in the electronic-grade silicon which is used to make transistors) back on.

The new material exists in a quantum halfway house between magnet and semiconductor - in the same way that much more complex materials such as ceramics which exhibit high temperature superconductivity exist in quantum halfway houses between metals and magnetic insulators. The research is of fundamental importance because it demonstrates, for the first time, a simple recipe for reaching this halfway house, whilst also suggesting new mechanisms for controlling electrical currents and magnetism in semiconductor devices.

Professor J F DiTusa of Louisiana State University and a co-author of the paper said: “It’s amazing that something which was thought to exist theoretically in mathematical physics could actually be found in an alloy which was simply formed by melting together a few common elements.”

Professor Gabriel Aeppli of UCL (University College London), another member of the research team and Director of the London Centre for Nanotechnology, added: “It might be possible to see similar effects in devices made using materials and methods of the type used to make laser pointers. This would put what we’ve seen firmly in the realm of that which can easily be achieved using current technologies.”

The first author of the paper, Dr N Manyala of the National University of Lesotho, said: “We are looking forward to investigating whether we can see these effects using thin layers of the same materials deposited directly on the silicon wafers. These wafers are the same as those used by mass market electronics manufacturers as the basis for integrated circuits.” Dr Ramirez, who is now with LGS-Bell Labs Innovations, echoed this thought, noting that “with the end of

Moore’s law in sight, mechanisms for controlling and understanding possible new information bits such as spins in solids are actively being sought after.”

Contact details:For further information, to speak to Professor Aeppli, or to obtain a copy of the paper (Doping of a Semiconductor to Create an Unconventional Metal, N Manyala, J F DiTusa, G Aeppli, and A P Ramirez), please contact Dave Weston in the UCL Press Office on +44 (0) 20 7679 7678 or [email protected].

About the London Centre for Nanotechnology: The London Centre for Nanotechnology is an interdisciplinary joint enterprise between University College London and Imperial College London. In bringing together world-class infrastructure and leading nanotechnology research activities, the Centre aims to attain the

Creating Unconventional Metals - International Team Discovers Quantum Halfway House between Magnet and Semiconductor

An unconventional metal: The magnetic bar magnets (called “magnetic moments”) associated with the mobile electrons (red arrows) responsible for electrical conduction and manganese atoms (green arrows) in manganese doped iron silicide (Fe1-xMnxSi). This figure depicts the coupling of the magnetic moments as the temperature is reduced from room temperature (top of the figure) where the magnetic dipoles are independent, to very low temperature (bottom of the figure) where coupling between the dipoles creates regions where the moments add to zero (light blue region). The existence of a population of uncoupled complexes (depicted here in the yellow region) down to the lowest temperatures results in the material being neither a magnet nor common semiconductor. External magnetic fields align these rare yellow regions to the magnetic field, switching on ordinary semiconducting behaviour.

critical mass to compete with the best facilities abroad. Research programmes are aligned to three key areas, namely planet care, healthcare and information technology, and bridge together biomedical, physical and engineering sciences: www.london-nano.com.

About UCL (University College London):Founded in 1826, UCL was the first English university established after Oxford and Cambridge, the first to admit students regardless of race, class, religion or gender, and the first to provide systematic teaching of law, architecture and medicine. In the government’s most recent Research Assessment Exercise, 59 UCL departments achieved top ratings of 5* and 5, indicating research quality of international excellence. UCL is in the top 10 world universities in the 2007 THES-QS World University Rankings, and the fourth-ranked UK university in the 2007 league table of the top 500 world universities produced by the Shanghai Jiao Tong University. UCL alumni include Marie Stopes, Jonathan Dimbleby, Lord Woolf, Alexander Graham Bell, and members of the band Coldplay: www.ucl.ac.uk.

About Louisiana State University:LSU is the flagship institution of the state of Louisiana and is one of only 21 universities nationwide holding land-grant, sea-grant and space-grant status. Since 1860, LSU has served the people of Louisiana, the region, the nation, and the world through extensive, multipurpose programs encompassing instruction, research, and public service. The University brings in more than $120 million annually in outside research grants and contracts, a significant factor for the Louisiana economy: www.lsu.edu.

About The National University of Lesotho:The National University of Lesotho is a growing institution striving to meet the needs of the nation, through producing competent and skilled graduates who can easily take up the call to assist in the development of Lesotho. The 80 hectare University site is situated at Roma (pop 8,000), some 34 kilometers south-east of Maseru, the capital of Lesotho. Roma Valley is broad and is surrounded by a barrier of rugged mountains which provides magnificent scenery. The University enjoys a temperate climate with four distinctive seasons: www.nul.ls.

About LGS Bell Labs Innovations:LGS is the successor to the former


Letter to the Editor Dear Editor: Further to the article which appeared in the summer 2008 issue of Magnews: E3 Academy enterprise welcomed by CBI Director-General as engineering graduate numbers hit crisis point, I would like to respond as follows:Paul Acarnley and the E3 Academy require a miracle to influence those not already committed to engineering.Engineering careers are not as “financially rewarding as any other”, as the article itself implies. During my 45 years in engineering, reality has been a shortage of engineers willing to work for the money on offer. The capitalist system offers a simple solution involving opening wallets. The frustrations of bureaucracy encourage good engineers to leave large companies so that they can innovate.

In the view of the scientifically and technically illiterate majority of the UK population, engineers are people with an IQ of 90 who repair appliances, as portrayed by many companies. Why have the institutions not re-branded with a series of protected titles for the range of levels, and excluding the technically tenuous from them as management responsibility itself is not the criteria? Although far from perfect, 50 years ago there was a successful system of schools, apprenticeships, technical colleges, polytechnics and universities, providing a multi-layered matrix of training, education and qualifications (the difference between education and training being “understanding”). With 3% of the population then being graduates, at the bottom end they had an IQ of 130, and were potentially good problem-solvers. In my experience, now 90% of “raw” graduates either don’t understand the basis of the subject, or can’t think straight, and often suffer from both afflictions. The other 10% (tallying with 4% of the population) range from acceptable to excellent. This is a predictable outcome in extending university entrance to those of average ability.

People are born with differing abilities and aptitudes. They receive different stimulation and develop at different rates. One size most definitely does not fit all. Scientists and engineers are abnormal. Only a fraction of 1% of the population have mind sets appropriate to high levels in these fields. Schools have largely stopped developing spatial awareness, mental visualisation, graphic representation of abstract concepts, and structured development by rigorous logic. The distribution of aptitude in these mind sets varies with gender. Those that do not have these abilities cannot appreciate them. Do we screen undergraduates for their aptitude?

Dumbing down at the “top end” is evident when comparing text books and examination papers from say 1890 and 1960 with those of today. In consequence, freshers are laggingone to two years behind. The rote learning at school destroys interest in studying subjects. As an example, dyslexics have been over-represented in the ranks of great scientists and engineers, as they have the right mind sets. But schooling now concentrates on memory and language, at which they are weak. Bright people can be ‘turned off’ by constant failure, and prevented from obtaining the entry tickets to higher education. Companies often ignore the need for post graduate training, even when they are able to define the skills and knowledge required to do a job, and assess these qualities in candidates.

So come on CBI, EEF, IET, IMechE, EC and Universities, get your acts together to define the terms, set the salary levels, and then bang the drum and shout loudly to get the government and the population to change their perceptions and fall into line.

Yours faithfullyJ L Tasker

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Please note that the above views are the views of the author and the editor of Magnews accepts no responsibility or liability in any way whatsoever for these views.

If you have any comments on the Letter to the Editor, or any other issues relating to magnetics or articles contained in Magnews, the Editor will be pleased to hear of them

Lucent and Alcatel Government Solutions business units. Beginning operations on 1 January 2007, LGS is an independent and wholly-owned subsidiary of Alcatel-Lucent’s North-American operations. Alcatel-Lucent is the leading provider of telecommunications and networking products and services worldwide. Delivering the promise of ideas through the power of Bell Labs technology, LGS continues to play a prominent role, on behalf of the US Government, in preserving the technological pre-eminence of America. We have a long and proven heritage of delivering highly reliable and secure network technology, and breakthroughs in the way the Federal Government communicates amongst itself, with its constituency and other jurisdictions, and around the world. LGS also has proven experience in forming alliances and partnerships with leading defense contractors, system integrators, and service providers: www.lgsinnovations.com.

Creating Unconventional Metals contd...


High Temperature, Flexible Nanoscomposite Electrically Insulating Coatings Professor Simon Hodgson, University of Teeside, School of Science and Technology [This paper was presented at the UKMAG one day seminar Advanced Electric Machines through Materials, held at TRW Conekt, Solihull on 15 October 2008 - members can access the full presentation on the Society’s website www.ukmagsoc.org]

The materials used for the electrical insulation of the windings in

electrical machines and generators have remained relatively unchanged since the earliest commercial applications. These materials, often termed varnishes, are essentially organic polymers, typically based on epoxy or polyester. Although some more exotic (and costly) polymers have begun to be used, there remains a fundamental limitation in the temperature capability of such organic materials with even the best performing available materials constrained to temperatures of below 250oC for long term use.

In practice the thermal degradation of these organic polymers is one of the major causes of failure of electrical machines, with hot spots in the windings generating temperatures sufficiently high to cause breakdown of the insulation. Even where failure does not occur, the need to limit the temperatures generated in the windings below the service limits of the polymers places a significant constraint on the current carrying capacity of the conductors and hence the power output of the machine, and/or requires the addition of secondary cooling systems to limit the winding temperatures with significant penalties of weight, cost and complexity.

Emerging applications for electrical machines and generators, particularly for the aerospace sector, are expected to require the ability to operate at

significantly higher temperatures with 400-500oC capability a basic design requirement. Such systems are essentially unrealisable with the current materials technologies used for electrical insulation. Long term exposure to such temperatures is beyond the capability of even the most high performance organic polymers and requires the consideration of new classes of materials. Nevertheless, the low cost, speed and ease of application, mechanical flexibility and high dielectric strength of traditional organic insulation materials represent a formidable challenge to alternative materials technologies to match.

In practice, there are no obvious candidate materials which can simultaneously provide all the desirable attributes of the currently used organic polymers plus the high temperature capability. This basic limitation of materials technology has essentially provided a constraint to the evolution of high performance electrical machines for almost a century. In this work, we develop an alternative design approach in which we consider the design requirements at different stages in the manufacture and service life of these machines. It then becomes apparent that in practice there is no single stage in the product lifecycle at which all the above properties are simultaneously critical and the fundamental design constraint can be freed. In particular, the key requirements of mechanical flexibility are critical

to the insulated wire production and particularly the winding and assembly processes, but less important once the winding is assembled in situ, whereas the high temperature capability is only important in service.

Based on this approach we have developed a new class of economical insulation materials, based on hybrid organic-inorganic nanocomposites, engineered to allow the functionality to be modified at different stages in the life cycle of the material. By appropriately distributing the organic phase at the molecular level, the mechanical characteristics can be adjusted to achieve the required flexibility for assembly, whilst the material can be designed to undergo controlled decomposition in situ to yield essentially inorganic high temperature insulation. Such materials can be successfully used to produce electrical windings with service temperature capability above 450oC. Here we will discuss the coating design, materials used, the roles of the phase distribution, filler type and morphology and the manufacturing process used to produce this new class of high temperature insulation materials for electrical windings.Prof Simon Hodgson, University of Teeside, School of Science and Technology

Corrosion Effects on Bonded Magnets in an Automotive Environment Dr Chris Riley, Magnet Applications Limited[This paper was presented at the UKMAG one day seminar Advanced Electric Machines through Materials, held at TRW Conekt, Solihull on 15 October 2008 - members can access the full presentation on the Society’s website www.ukmagsoc.org]

Bonded NdFeB magnets have many advantages over their sintered

counterparts in terms of “net shape” manufacture, alternate molding techniques, higher resistivity and magnetisation shaping. However, despite the fact that the polymer into which the NdFeB powder is bonded offers some degree of corrosion protection, often sufficient for everyday applications, they are still susceptible to high degrees of corrosion in more extreme environments.

One application area where there has been growing interest is the design of permanent magnet motors for electric water coolant pumps in the ‘more electric’ or hybrid electric vehicles. This presentation describes one such application for which a small brushless DC motor has been designed based on polymer bonded magnet technology using standard isotropic NdFeB magnet components. The pump has been designed to be used for either DI water for a fuel cell application or

ethylene-glycol/water mixtures which could reach temperatures up to 90°C. The design of this pump combines the motor and pumping functions into one integrated product. The rotor of the pump consists of a multi-pole magnetised bonded NdFeB ring magnet fixed to a mild steel rotor hub and shaft which is mechanically coupled to the impeller of the pump so that when the pump is in operation, the pumping liquid flows around the permanent magnet rotor as well as the impeller.


In order to protect the magnets, they must either be coated with a suitable coating resistant to DI water and ethylene-glycol or completely sealed from the hot liquid using a stainless steel welded can. The issues with this latter option are that the welded can adds a significant cost to the manufacture in materials, assembly and testing to ensure there are no leaks. On top of this, the airgap of the motor has to be increased to accommodate the can, which in turn increases the volume of magnet needed to generate the required airgap field of the motor.

Sol-Gel is a chemical process which can be used to create thin film coatings (typ 1-5µm) which can be applied to substrates by conventional techniques such as ‘dipping’ or ‘spraying’. One of the advantages is that the ‘recipe’ for the Sol-Gel formulation can be altered depending on the environment in which it is to be used and the degree of flexibility in the coating that is required. In the case of water pumps, the coating could be altered depending on whether they are pumping fuel, oil or water based liquids. Also as the coatings are very thin they can be used to coat the actual magnet powder in the bonded magnet to add an extra degree of protection.

This presentation focuses on two separate investigations. The first half covers a study into the effectiveness of a number of commercially available and Sol-Gel coatings for bonded magnets in hot liquid coolants such as ethylene-glycol or DI water where it has been shown that although surface coatings can be effective in protecting against surface corrosion the magnets experience a large irrecoverable loss in magnetic properties. The second part will show the findings of a more fundamental investigation carried out by Birmingham University into the causes of this high loss in coercivity which was believed to be related to the production and subsequent absorption of hydrogen by the NdFeB flakes during the corrosion process and whether an alternative binder in the bonded magnet can be used to limit the corrosion.

8 Pole Bonded Magnet Rotor100W, 5000rpm Water Pump

Corrosion Effects on Bonded Magnets in an Automotive Environment contd...

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TGA and mass spectrometer results for MQ powder

Members training courses and workshopsMembers: please let us have details of your training courses and workshops for free inclusion in Magnews.Contact: [email protected] coated magnet


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10th International Workshop on 1&2 Dimensional Magnetic Measurement and Testing (1&2DM), 1-3 September 2008, at Cardiff UniversityThe first three days of September saw

the 10th International Workshop on 1&2 Dimensional Magnetic Measurement and Testing, which this year was held at Cardiff University and hosted by the Wolfson Centre for Magnetics. Talks and poster sessions were presented over two days covering a wide range of topics, from advances in magnetic measurements, to the standardisation of measurement techniques. Over 60 delegates attended the conference, making it one of the most popular workshops in the event’s 17-year history.

The majority of delegates arriving in Cardiff on the Monday evening were greeted by grey skies and thunderous showers, but this did not dampen their spirits as on the first night all were invited to unwind and relax with a drink in the conference centre’s lounge. Formerly damp delegates soaked up the atmosphere, as well as a beer or two, and began liberally discussing matters of research and the events scheduled over the following two days.

On Tuesday morning the serious business of presentations began with the opening remarks given by Dr David Grant, Vice-Chancellor of Cardiff University, Prof Hywel Thomas, Director of Cardiff’s School of Engineering, Dr Johannes Sievert, Chairman of the International Committee, and Prof Tony Moses, Workshop Chairman. This was followed by a plenary lecture presented by Mr Masao Yabumoto of Nippon Steel, who reviewed the wide range of physical and optical techniques used to measure magnetostriction in electrical steels and emphasised the industry’s need to move towards standardisation. Mr Yabumoto continued on this theme by reporting on the progress of the IEC/TC68 project already underway, which is seeking to outline such an industry standard for measuring magnetostriction.

Dr A Kedous-Lebouc, of G2ELab, Grenoble, France, presented the recent developments in magnetic refrigeration at Grenoble and Dr Pfutzner spoke about thin film technique for localised magnetic analysis in laminated cores.

The morning session concluded with Dr Carlo Ragusa of Politecnico di Torino, discussing his investigation of grain-oriented and non-oriented electrical steels under alternating unidirectional and rotating field conditions. Both fieldmetric and thermometric approaches were used to independently evaluate loss. When compared, the results from these demonstrated a remarkable level of agreement between the two techniques.

The afternoon session focused on potential magnetic measurements applicable to the industry. Dr Michael Hall, from the National Physical

Laboratory, discussed open circuit measurements which are being used to develop efficient modelling predictions and building devices for environmentally-friendly transport applications. It is difficult to realise some operating environments in the laboratory whilst trying to incorporate the yoke for a closed loop system, and so it becomes desirable to instead use an open-circuit measurement. To account for the demagnetising field, the system has been calibrated by measuring the field strength at increasing distances from the source and the effective closed-loop measurements on the surface of the material can then be determined by extrapolating back to the source.

Mr Richard Wood, of the Wolfson Centre for Magnetics, also discussed open-circuit measurements and examined the problem of flux divergence when locally magnetising sheets of electrical steel using a single-yoke magnetic measurements system. Guard yokes

were introduced in an attempt to resolve the problem and thus increase the accuracy of the measurement by creating a more uniform distribution of flux directly under the central measuring yoke.

Day 1 ended with a poster session, where delegates had the chance to discuss the ideas introduced over the course of the day and view technical posters, the majority of which were supplied by research students. These covered a diverse range of topics such as magnetic modelling, magnetostriction, thin films, harmonics and magnetic refrigeration. Most embraced the opportunity to get feedback on their

work from the senior academics and members of industry present at the workshop.

A visit to the Welsh capital would seldom be complete if delegates were not treated to a traditional Welsh banquet and nobody was disappointed by the magnificent feast that followed the eventful first day. Cardiff Castle, a prominent location in the heart of the city centre, was the venue and after a short tour of the clock tower, all of the guests were welcomed into the banquet hall with glasses of mead wine. The hall was rife with cheerful banter as the hosts ‘Nosweithiau Bute-iful Nights’ entertained the crowds with a wealth of Welsh songs and a

number of amusing anecdotes of Welsh tradition. As the evening drew to a close, all had an opportunity to reflect over the day’s events as they sat down for a quiet drink in the Castle’s bar.

On Wednesday morning Prof Jian Guo Zhu, of University of Technology, Sydney, began the presentations by discussing the application of soft magnetic composites (SMC). These pure iron powders have certain advantages over electrical steels when fabricating novel motor cores, because of powder metallurgies potential for compressing SMCs into complex 3-dimensional shapes. This feature has been exploited by developing a 3D magnetic property tester, which is capable of measuring the magnetic properties of an SMC under 3D magnetisation. Using this system it has been possible to develop modelling tools that have optimised the design of numerous SMC motors. contd on page 21

Delegates enjoying the workshop banquet at Cardiff Castle


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Delegates at the 1&2 DM Workshop

1&2 Dimensional Measurement and Testing Workshop [contd from page 19]Dr Zurek, of Megger Group, showed how anisotropy of power loss and permeability for GO electrical steel

is symmetrical. Mr Wakabayashi, of Oita University, discussed the vector relationship between the magnetostriction, the magnetic field vectors and the internal stress and its importance in reduction of noise in transformer cores. Mr Ranvah, of Cardiff University, presented a magnetostriction model based on Jiles–Atherton theory which couples the magnetic and magnetostrictive hysteresis and helps to study the effect of mechanical stress on them. Prof Pfützner, of Vienna University of Technology, reported his study of the magnetic state of model transformer cores using a multi-parametric compound sensor. Dr Miyagi, of Okayama University, explained how the use of diagonal excitation coil can increase the measurement accuracy of 2 dimensional magnetic properties of electrical steel at high flux density. Miss Fonteyn, of Helsinki University of Technology, discussed the measurements of magnetic properties of electrical steel sheets under alternating field with a vertical yoke system.

One topic attracting a good deal of attention at the conference, was that of magnetic shielding, with some of

the keener e x p o n e n t s of shielding r e s e a r c h gathering to discuss ideas in a break out session on the first day of the conference.

This subject took centre stage again on Day 2, when Prof Yasuo Okazaki, of Gifu University, talked about the effectiveness of

shielding with grain-oriented electrical steel under alternating fields of up to 100 kHz.

Beginning by validating the need for shielding and identifying some of the sources of electromagnetic radiation within the household, Prof Okazaki continued by comparing the shielding effectiveness of electrical steels when aligned in either the rolling or transverse directions. The results showed that eddy currents, because of the skin effect in the material and conductivity of the join, play a significant role in the success of the shielding. Dr Matsuo, of Kyoto University, concluded the morning session by presenting measurement simulated results of transient vector hysteretic property of electrical steel sheets.

The afternoon session commenced with Mr Ahlers, of Physikalisch-

Technische Bundesanstalt, discussing the precision of measurements of magnetic material properties using a SQUID susceptometer. Prof Todaka, of Oita University, pointed out the counter clockwise/clockwise (CCW/CW) effect on rotational loss measurement under high magnetic field and its compensation. Dr Kedous-Lebouc, from Grenoble-INP, discussed magnetic properties, characterisation and modelling of magnetic materials required for high speed electrical machines. The final talk was the measurement and modelling of magnetic properties of electrical steels at high flux densities for fault current limiters presented by Prof Jiles of Cardiff University.

To end Day 2 of the workshop, visitors were given a tour of the Wolfson Centres laboratories, where demonstrations of dynamic-domain observation and magnetostriction measurement drew a great deal of interest. Following the tour a final farewell buffet allowed delegates a welcome opportunity to relax before their long journeys home.

The location of the 11th International Workshop on 1&2 Dimensional Magnetic Measurement and Testing in 2010 has already been announced and will be held at Oita, Japan.Manjunath Balehosur, Sakda Somkun and Steven Turner, Wolfson Centre for Magnetics, Cardiff University

Speakers at the 1&2 DM Workshop


Table 2 Percentage changes of used sintered magnets in Japan (1996-2003)

25 Years of the NdFeB Magnet Industry[this article continues from the Summer 2008 issue of Magnews]

Sintered NdFeB magnet applications

The advent of sintered NdFeB magnets was in 1983. It was the time of the popularisation and miniaturisation of computers, office automation and home electronics. Magnets with high energy products are vital for motors to reduce their size and weight, whilst their torque is increased. Thus, NdFeB magnets were put to best use, which is evident in the applications of sintered NdFeB magnets in developed countries. In Japan VCM (voice coil motors), MRI (magnetic resonance imaging), and motors/generators are the three major applications of sintered NdFeB magnets. NdFeB magnets are widely used in HDD (hard disk drives) of computers, consumer electronics. VCM is the biggest application of NdFeB magnets. The proportion of magnets used for MRI is relatively stable and the motor/generator market shows the greatest growth. NdFeB magnets are also used in communication and acoustic devices.

Applications in Japan

Sintered NdFeB magnets are widely used in HDD of computers and consumer electronics. Although VCM is the largest application of NdFeB magnets, its weight percentage has reduced continuously from 57% of the total in 1996 to 35% in 2003. This is because the most advanced magnets with energy products ≥ 48 MGOe are used. Consequently the weight per piece is much reduced. Now HDD are widely used not only in PCs, but are used as memory in video systems in televisions, car navigation systems and mobile phones etc. The weight of the VCM piece for a 2” HDD is 5-7g, while the weight of the VCM piece for a 1” or 0.8” HDD is far smaller at 0.036 gram, ie a 1 kg magnet block can produce 27,000 VCM magnets. The size of such VCM magnets is about 3x2x0.8mm with an unsymmetrical shape and so they are difficult to prepare. This makes its price

rather high. In other words, material cost for such VCM magnets is minor and negligible.

The MRI magnet sector is relatively stable and ranges between 13-17%. MRI is used not only for medical purposes, but digital MRI with low magnetic fields can be used for quality control of agricultural products and space-orientation applications etc.[19].

There has been an increase in acoustic and communication devices in recent years. Here small size magnets are used

for applications such as micro-speakers, pick-ups for CD and DVD drives, vibration motors in mobile phones and audio-systems for automobiles instead of ferrite magnets. The section of magnets used for motors/generators shows the most growth. The proportion used for certain applications varies year

by year; their changes during 1996-2003 are listed in Table 2[3].

A remarkable increase in the motor application sector has been observed since 1995. The driving force behind this increase is closely related not only to the performance improvement of the magnets, but also to progress in motor design. This includes SPM (surface permanent magnet) type motors and IPM (interior permanent magnet) type motors using high performance magnets. The SPM type is mainly applied in

servomotors for fabric automation, office automation and elevator lifting motors. The IPM type is expanding

into many applications, including compressor motors. The reason for the increased use of the IPM type is that simple rectangular shaped magnets can be used. These give a significant cost saving in preparation and assembly in comparison with segment magnets. IPM-type motors have been adopted by Toyota and Honda for their Hybrid electric vehicle (HEV). The magnets used are the 38UH grade with (BH)MAX= 38 MGOe, IHC ≥ 25 kOe, which can be used at temperature 180-220oC.

One possible rotor structure of high speed brushless DC motors used for compressors is an IPM type with four

sintered NdFeB magnets of 39EH or 40UH. The magnet plates are inserted into slots in the rotor as shown in Fig 10a. Alternatively, the rotor can be designed as a SPM type shown in Fig 10b. Here a radially-oriented ring made from MAGFINE is installed on the rotor surface.

Applications in China

A proportion of sintered NdFeB magnets made in China is exported into the international market; the rest is used in the domestic market. According to the published data of the China Customer Office the export tonnage and value of NdFeB magnets during 1998-2007 are shown in Figure 11.

When studying the export oriented character of NdFeB magnets made in China for different applications care must be taken. Until 2002 most NdFeB magnets were exported. Consequently the use of NdFeB magnets in China was quite different from that in developed countries.

Figure 11 shows that the NdFeB magnet industry in China in 1998 was export oriented with 89% of her total magnet

VCM Motor/

generatorMRI Acoustics Communic-

ationOthers

1996 57% 14% 16% 3% 5% 5%1997 58% 15% 14% 3% 6% 4%

1998 55% 15% 14% 3% 8% 5%1999 50% 20% 14% 3% 10% 3%2000 47% 24% 13% 2% 11% 3%2001 43% 29% 16% 2% 9% 2%2002 36% 32% 17% 4% 9% 2%2003 35% 34% 15% 8% 8% 2%

Inserted by sintered NdFeB(IMP) with a radially-oriented ring(SPM)

Motor body: φ112xL60 mm 4 pieces of sintered NdFeB, 39 MGOeMagnet weight 84 g

Motor body: φ90xL55 mmRadially oriented Ring MF25, 25 MGOe Magnet weight 130 g

(a) (b)Figure 10 High Speed Brushless DC Motor (Air Compressor)(a) IPM design with 4 pieces of 39EH or 40 UH sintered NdFeB(b) SPM design with a ring made from MAGFINE


production being exported and only 11% being used in the domestic market. The fraction of magnets used in the domestic market has increased significantly in the last ten years and since 2002 more than half of the annual NdFeB production has been used in the domestic market. The application of NdFeB magnets in China is different from that in developed countries. There are three traditional applications: speakers, separators and magnetisers (including dewaxers used in oil fields). Low grade uses include magnetic buttons for clothing, boxes and furniture. The high-tech applications were formed after 2003. The applications of NdFeB magnets in China are displayed in Figure 12.

Note: EB—electric bicycle; EAV—electro assisted vehicle.

The applications of NdFeB magnets in China can be divided into three groups:

1) Traditional applications including speakers, separators and magnetisers formed the largest group. It occupied 64.2% of the total in 1998 but was reduced to 35.2% in 2007. Among the traditional uses, speakers are the biggest section at

32.2% in 1998, falling to 25% in 2007. The magnet volume used for separators is also declining; it was 18% in 1998 and fell to 8% in 2007. Magnets used for magnetisers (including dewaxers widely used in the petroleum industry and oil fields) are reducing more significantly: they occupied 14% in 1998 and dropped to 2% in 2007. In general the traditional use is around one third of the total.

2) Low grade magnets such as those made in Cixi city, are mostly used as magnetic buttons in cases, clothing and furniture [5]. The volume of such use was around 13-16% of the total during 1998-2007. Such applications may retain their market share for a certain

period of time - its absolute tonnage may even still be increased but its percentage should decline in the long term. It is clear that such applications are neither economical nor reasonable considering the limitation of rare earth resources.

3) High-tech applications including MRI, VCM, CD pick-up, DVD/CD ROM, mobile phone, cordless tools and EB+EAV, appeared from 2003. The share of this sector is increasing.

N d F e B m a g n e t s produced in China are used mainly in the domestic market, and have been since 2002. In the last decade the magnet v o l u m e s used in the d o m e s t i c market have i n c r e a s e d

year by year. High-tech applications have gained market share since 2003, increasing from 22.2% in 1998 to 48.5% in 2007. The percentage of traditional use has fallen from 64.2% in 1998 to 35.2% in 2007. The low grade use remained around 13-17% during 1998-2007.

The electric bicycle (EB) has become rather popular in south China since the late 1990s. Key to the design is a DC motor made with sintered NdFeB magnets [21]. The price of rare earth has significantly increased since 2006, and the output of EBs has increased at the same time. Therefore, a special grade of NdFeB was developed with the intention of reducing magnet cost. Gadolinium (Gd) is used to replace Dysprosium (Dy) as the current price of Dy is ¥800/kg, while price of Gd is ¥100/kg (at time of writing)! It should be noted that such a low price of Gd is abnormal as there has been no use for Gd for a long time.

The electrical bicycle output and tonnage of NdFeB magnets used in electrical bicycles is shown in Figure 14.

The production of electric bicycles in recent years has increased too fast generating severe competition between the manufacturers and causing quality problems. To reduce production costs unqualified magnets are used, which reduces the life time and reliability of the DC motor made with NdFeB magnets. Customers have consequently lost interest and sales dropped significantly in 2004. This forced the manufacturers to improve the quality of their products and now more advanced DC brushless motors are used. 5,700 tons and 2,385 tons of magnets are used each year for electric bicycles and electric assisted vehicles respectively.

Magnets used for CD pick-ups and DVD/CD ROMs are another big application in this section. They represent 5.2% and 8.8% of the total in 2007, respectively. Magnets used for VCMs and RMI are

Figure 11 Export and domestic NdFeB tonnage, export market value and NdFeB price in China

Figure 12 Distribution of sintered NdFeB in applications in China

0

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25 Years of the NdFeB Magnet Industry contd...


3% and 2.7% in 2007. They are not so big at present but they are expected to increase in the future. Use in cordless tools and mobile phones consumed 6.2% and 6.5% respectively in 2007. The use of motors in automobiles is not yet included. The high-tech sector has the highest growth rate. It will be more than half of the total shortly.

In 2007 the high-tech sector was 49% of the total, traditional uses

including speakers, separators and magnetisers occupied 35% and low grade uses occupied 14%. Numerous new applications will appear in the 21st Century. Much improvement in both quality and quantity of NdFeB magnets will take place in next decade and consequently customers all over the world will enjoy cheaper and better NdFeB magnets!

The use of NdFeB magnets for MRI and VCM are increasing but their percentages are still relatively small (in 2006 it was 3% and in 2007 2.7%). The use of DVD/CD ROM is the second largest of the high-tech applications with 8.8% of

total in 2007. The use for mobile phones increased quite fast, although its amount was only 6.5% of the total in 2007. Use for cordless tools was 6.2% of the total in 2007.

The recently developed electric bicycle (EB) was the biggest application in the field of high-tech use; it reached 12.6% of the total in 2007. The DC motors used in electric bicycles are made with 380g sintered NdFeB magnet in each

motor. The manufactured output of electric bicycles is more than ten million pieces annually - one can imagine the volume of NdFeB m a g n e t s needed! If the use for electric assisted vehicle (EAV) and electric vehicle (EV) is included, then

the use of this section will grow rather fast in the near future.

The share of high-tech applications in China is increasing rather quickly: it was 22.2% in 1998, rising to 34%, 35.2%, 36.9%, 42.2% and 48.5% in 2003, 2004, 2005, 2006 and 2007 respectively. Now it is half of the total output. Considering the uses for various types of automobile motors, the volume of this section may grow rapidly in the future. It may exceed half of the total soon.

By the end of the 1990s the electric bicycle was popular in South China. An NdFeB motor is used for its drive,

and a special grade of NdFeB has been developed for such use. In the beginning 38H and 35SH was used, later people found that 35H is suitable for such use. The price of rare earth has dramatically increased since 2005, and the use for electrical bicycles is so large now that a special grade of magnet has been developed. Gd is used to replace Nd and Dy in magnets. The reason is obvious; the current price of Nd is ¥340/kg, Dy is ¥ 800/kg, Gd is ¥100/kg. It should be noted that the abundance of Gd is less than both Nd and Dy. In other words, the price of Gd should be higher than that of Nd and Dy. The current situation is due to the storage of Gd for quite a long time.

Further improvement and development of NdFeB magnets will be made in the 21st Century. Quantity and quality will be increased in the magnet industry in China during the next decade. As a result customers all over the world will enjoy cheaper and better magnets!

Developmenty of the rare earth magnet industry in China and developed countries

Rare earth magnets in developed countries are typically new materials used in high-tech fields with special requirements, the price of which is rather high. Due to unique requirements the hardware for the preparation of such magnets is quite expensive. Accordingly, the development costs for the software are also rather high. Thus, the rare earth magnet industry in developed countries is described as “Three Highs”, ie high investment, high output, high return. The rare earth magnet industry in developed countries is regarded with special respect and enjoys certain preferential treatment.

The situation in China is completely different. Chinese magnet producers are unable to get expensive equipment to prepare magnets. Therefore, they have to make changes in the software to remedy the weaknesses of the hardware. The most obvious example is the “two step forming process” adopted by most Chinese magnet manufacturers to replace the advanced automatic press. In China a simple press and steel mould is used for pre-forming block magnets, then the block is put into an iso-static press to increase its density. The equipment cost of such forming process is only 1/10-1/8 of an imported press.

The sintering furnace is another example. Products at different stages of sintering are placed in different chambers of a

Figure 13 Share change of different application sectors in China

0%

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EB, x10000 NdFeB, t on

Figure 14 Electric bicycles production and tonnage of sintered NdFeB used



continuous multi-chamber sintering furnace. Such furnaces are excellent and very productive, but the costs are too high. So most Chinese magnet manufacturers use single chamber furnaces in which the sintering cycle is longer and the power consumed is greater. However, the performance of the products is

acceptable. The price of a multi-chamber furnace is at least 10 times higher than that for a single chamber furnace! Recently, a sintering furnace with three chambers has been developed. The whole sintering process can be finished within the same furnace and cycle time is comparable with multi-chamber furnaces. The price is 1/5 of that of an imported one, and is three times higher than a Chinese made single furnace. Now the most popular domestic made sintering furnace is a furnace with double chambers, its batch volume is 300 kg.

In order to eliminate the existence of α-Fe in the alloy, strip casting methods have been used to replace conventional ingot in Japan since the middle of the 1990s. Such processes much improved both the magnet performances and the performance consistency. But the price of strip casters is too high to be accepted by the Chinese magnet manufacturers. Thus the plate ingot with thickness 10-15 mm (both sides water cooled) is widely used in China, which can be prepared by conventional induction smelting furnace. In this way most α-Fe in ingot is eliminated. By using such plate ingot,

magnets with (BH)MAX = 45 MGOe are prepared stably and reliably.

Recently, the Japanese strip caster maker (ULVAC) made a joint venture with China North Vacuum Technology Co Ltd to prepare strip casters specially. The price of the strip caster was reduced

to one third of the original one. Now a local Chinese furnace manufacturer has built a strip caster with 200 kg alloy per melt. It works quite well and its price was ¥1.3x106, such price is acceptable to Chinese magnet producers.

It is well known that hydrogen decrepitation is a very effective way to prepare the powder

needed for powder metallurgy process. But the existing equipment for hydrogen decrepitation is not only too expensive, but also ineffective for use. Now, new equipment for hydrogen decrepitation has been developed, which eliminates all possible defects, its working cycle is one

third to one fifth of that of an imported one and the total cost is one fifth to one

eighth of the former.

Based on the experience of many years, we strongly believe that, in time, Chinese magnet producers will develop more advanced hardware. The product level will be comparable with that of developed countries, but the price will be the best and lowest. This is key to keeping the position of China magnets in the global market.

Price – Quality – VolumeThe higher the price is, the better the quality is. In other words, the price of products is directly proportional to their quality. Price also depends on sales volume: the bigger the sales volume, the lower the price, ie price is inversely proportional to its sales volume. The correlation between price, quality and sales volume can be expressed as triangle or pyramid shown Figure 16. High grade products are located in the top of the pyramid (zone 1). The price is high, but the volume is limited. The middle part (zone 2) means middle price and its volume is much greater than the top. The price in the bottom part (zone 3) is much lower in comparison with the top and its volume is expanded significantly as well. Each company should make clear about its position in the market, ie its location in this pyramid - then its business will run successfully and freely.

SmCo magnets formed the majority in the high performance magnet market in the

1980s; magnet prices were high and the market volume was limited at that time. Since the arrival of NdFeB magnets, the price of which is comparable with SmCo, its performance has improved. With the popularisation of NdFeB magnets the pressure on price reduction increased. The products of “Three Highs” could hardly meet the market demand. The products of China, which followed the philosophy of “Two Lows and One High”, ie low investment, high output, low profit, were just what were required by magnet customers all over the world.

Consequently, the jump in NdFeB output in China since 2002 was inevitable!

The starting point and the targets of the rare earth magnet industry in developed

Figure 15 Application distribution of NdFeB magnets in China (2007)

4% 3% 6%9%

7%7%

13%25%

8%2%

14% 2%

MRI VCM CD pi ck- up DVD/ CD ROM Mobi l e phone ToolEB+EAV Speaker Separ at or Magnet i zer Low gr ade ot her

|← Market volume (sales volume) →|

Figure 16 Correlation between price, quality and sales volume

Price Quality



countries and in China are quite different. Obviously, the rare earth magnet industries in developed countries and China follow different paths. Consequently, the acceptability of their products in the global market is also quite different. In the early 1980s, when NdFeB magnets appeared, the output of developed countries was dominant (85% compared with China's 15% in 1983). Twenty four years later, in 2008, a dramatic change has occurred: the output of developed countries is 21.5% (Japan 19.8%, Europe 1.7%, USA 0%) of the total, but the output of China is 78.5% of the total!

It is fortunate that China did not build up a rare earth magnet industry following the “Three Highs” philosophy as seen in the developed countries, but followed the philosophy of “Two Lows and One High”, which is able to keep the price low, and to meet the quality requirements from customers. Thus, orders all over the world are now sent to China. It is just what Chinese magnet producers have dreamt of day and night. In fact it is return for their many years of efforts. It is most important for Chinese magnet manufacturers to keep in mind the gaps between them and developed countries, to do their best to eliminate existing gaps as soon as possible. They must renew their hardware, build up a well trained technical team and quality control team. Otherwise the current favourable situation may disappear quickly, just as a flash in the pan. The Chinese magnet industry should be strengthened further, so it can withstand the storms of market without damage.

REFERENCES[1] M Sagawa, S Fujimura, M Togawa, H Yamamoto & Y Matsuura, J Appl Phys, 55, No 6, Part II A(1984) 2083[2] Y Kaneko, Technological Evaluation and Application Trends of NdFeB Sintered Magnets in Japan, Proc of 18th Int Workshop on HPMA (Annecy, France, 2004), vol 1, p40-51 [3] S Hirosawa, Recent Developments and Future Perspectives of Nd-Fe-B Permanent Magnets for Automotive Applications, BM News, No 35, 2006, 3, 31, p135-154[4] J J Croat, Technical Report of Magnequench, Delco Remy Div of GM (1990)[5] Y Honkura, Automotive Motor Innovation with Anisotropic Bonded Magnet, Proc of 19th International Workshop on REPM and their Applications (Beijing, China, August 30 – September 2, 2006), p231-239[6] Y Luo, Development of NdFeB Magnets in China, Proc of 11th International Workshop on REPM and their Applications (Pittsbugh, Pennsylvania, USA, October, 1990), p491-505[7] Y Luo, Current Status of Global

NdFeB Magnet Industry, BM News, No 33 (2005.3.31), p122-151[8] Y Luo, The Role of China’s Rare Earth in the Global, Proc of 16th Int Workshop on REM and their Applications (Sendai, Japan, August, 2000), Vol 1, p25-38[9] P Wheeler, private communication (June 28, 2000)[10] Jia Gui-yuan, Jia Yin-yang, Proc of 2004 China Magnet Symposium (Garden Hotel, Xian, China, May, 2004)[11] Jia Gui-yuan, Alnico Magnet Industry in China, Proc of 2004 BM Symposium (Hotel Lungwood, Tokyo, Japan, Dec 3)[12] Zhang Jian-liang, Current Status of Hard Ferrite Magnet Market & Raw Materials in China, Proc of 2004 BM Symposium (Hotel Lungwood, Tokyo, Japan, Dec 3, 2004)[13] T K Clagett, Current Status of Ferrite Magnet Production & Raw Materials in The USA and Europe, Proc of 2004 BM Symposium (Hotel Lungwood, Tokyo, Japan, Dec 3, 2004)[14] Yung-pil Yang and J J Croat, The Current Status and Future Outlook of The Bonded Neodymium Magnet Industry, Proc of 2004 BM Symposium (Hotel Lungwood, Tokyo, Japan, December 3, 2004)[15] M Sagawa, 20 Years of NdFeB, Proc of 2004 HPMA’04 (Annecy, France, August, 2004), vol 1, p7-11

[16] M Katter, speech at 2004 HPMA’04 (Annecy, France, August, 2004)[17] Sam Liu, Lee Don, Huang Mei-qing, Ashil Higgins, Shen Yu-hui, He Youngson, Chen Christina, Research and Development of Bulk Anisotropic Nanograin Composite Rare Earth Permanent Magnets, Proc of 19th International Workshop on REPM and Their Applications (Beijing, China, August, 2006), p123-135 [18] Y C Yang, Proc of China Magnet Symposium 2004 (Beijing, China)[19] Y Luo, Application of New Technology and New Equipment in NdFeB Production, Journal of Magnetic Materials and Devices, Vol 37, No 5 (2006) p1-5 [20] A Asfour et al, Digital MRI at Low-Field: Promising New Avenues for Permanent Magnet Flux Sources, Proc of 18th International Workshop on HPMA (Annecy, France, August, 2004), Vol 2, p609-615[21] Y Luo, Note on Visit to NdFeB Magnet Plant in Cixi and Electric Bicycle Plant in Nanjing, Magnetic Materials and Devices, Vol 36, No4 (2005), p1-3.

Professor Yang LUO, IEEE TC-15 Voting Member, Beijing, China [email protected]


STUDENT BURSARY SCHEME As part of its role in securing the future vitality of the magnetics community, the UK Magnetics Society has introduced a competitive bursary scheme to assist postgraduate students to attend international conferences. A total of 5 x £100 bursaries per year are available to support attendance at conferences of international standing in the UK or abroad, in subject areas which reflect the interests of the UK Magnetics Society membership. The award of a bursary is intended to acknowledge the student’s contribution to the magnetics community and act as a catalyst for attracting additional support.

The following eligibility criteria will be applied in selecting students: • restricted to full-time postgraduate students, ie not contract research

staff; • restricted to students from institutions which are members of the UK

Magnetics Society; • students should be presenting a paper, either poster or oral; • applications from students presenting a paper on collaborative work between two or more members of the UK Magnetics Society (academic

or industrial partners) will be particularly welcome; • successful recipients of student bursaries are requested to provide a brief review of the conference to appear in a subsequent issue of Magnews.

DENNIS HADFIELD MEMORIAL PRIZE In addition to the Student Bursaries, the annual Dennis Hadfield Memorial Prize of £100 will be awarded to the best Student Bursary conference report published in Magnews each year, and will be given out at the annual Ewing Event, held each December. The prize winner will be invited to attend the Ewing Event free of charge.


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This year the regular UK Magnetics Society’s CAD exhibition/seminar offers a strong technical programme consisting of presentations from the users of a range of software tools and packages for electromagnetic design and analysis. The presentations will give an insight into how these tools are applied to model a wide range of electromagnetic devices and the particular challenges encountered, as well as highlighting the latest developments in the available modelling capabilities; primarily presented from a user’s perspective, and a diverse range of industries and applications will be represented. The keynote speech will be given by Professor Jan Sykulski of the University of Southampton. To support the technical presentations, there will be an exhibition with demonstrations of the latest CAD software from the developers and vendors, which will offer an excellent opportunity to discuss modelling requirements with key players in the industry.from 0900 REGISTRATION/COFFEE Chairman: Dr John Cullen, Rolls-Royce plc1000 WELCOME/INTRODUCTION 1010 Modern Design Optimisation Exploiting Field Simulation, Professor Jan Sykulski, University of Southampton, School of Electronics and Computer Science 1040 Accurately Predicting the Performance of Linear Induction Motors, Dr Denis Edwards, University of Sussex, Dept of Engineering & Design 1110 Practical Application of CAD in a Hgh Power Density Motor for a Very Short-Duty Aerospace Actuator, Alastair Flew, Electro-Kinetic Designs Limited1140 Does the World Need Yet Another Finite Element Programme? Professor Dave Rodger, Bathwick Electrical Design Ltd 1210 LUNCH/EXHIBITION

Chairman: Dr Alex Michaelides, Vector Fields1340 End User Customisation of Quickfield Software, Peter Dickson, Pac-Rim Engineering Services Inc 1410 Modelling of Advanced Electromagnetic Devices, Dr David Powell, Magnomatics Limited1440 TEA/COFFEE1510 Insulation Design for 800KV DC, David Wright, AREVA T&D UK Limited1540 Improvements and New Developments in Generators: Requirements on Finite Element Analysis, David Gerada, Cummins Generator Technologies1610 END visit www.ukmagsoc.org, or telephone +44 (0)1235 770652 to register for this event

UKMAG forthcoming seminars

19 November 2008: Permanent Magnets in Extreme Environments, at the University of Birmingham, Department of Metallurgy and Materials

The increasing demand for permanent magnet based electrical systems has provided materials manufacturers with new challenges to combat the hostile environments in which many of these systems operate. Extreme temperatures and aggressive environmental operating conditions have meant that permanent magnet materials and supporting hardware require higher levels of corrosion protection and temperature stability while maintaining acceptable operating performance. This seminar describes some of these challenges and the developments in materials to meet them.from 0900 REGISTRATION/COFFEE Chairman: Dr Andy Williams, University of Birmingham, Dept of Metallurgy & Materials1000 WELCOME/INTRODUCTION 1015 High End Corrosion Protection Coatings for Rare-Earth Permanent Magnets, Dr Lothar Zapf, Vacuumschmelze GmbH, Germany1045 Enabling Melt Spun NdFeB Magnets in Under the Hood Applications, Dr David Brown, Magnequench Technology Centre, Singapore1115 Key Metals in Extending Environmental Tolerance of Rare-Earth Magnets, David Kennedy, Less Common Metals Ltd1145 The Application of Permanent Magnets in Oilfield Drilling Tools, Nigel Hale, Schlumberger-Stonehouse Product Centre 1215 LUNCH/EXHIBITION

Chairman: Dr Chris Riley, Magnet Applications Limited1345 The Behaviour of Rare Earth Magnets in Reducing and Oxidising Atmospheres, Professor Rex Harris, University of Birmingham, Department of Metallurgy and Materials1415 Linear Direct-Drive Permanent-Magnet Generators for Ocean Wave Energy Conversion, Dr Henk Polinder, TU Delft University, The Netherlands1445 TEA/COFFEE1515 Design Consideration for the MICE Target Actuator on the ISIS Accelerator, Dr Chris Booth, University of Sheffield, Dept of Physics and Astronomy1545 Samariam Cobalt Magnets in Extreme Temperature, Radiation and Space Environments, Richard Frolish, Electron Energy Corporation, USA1615 END

visit www.ukmagsoc.org, or telephone +44 (0)1235 770652 to register for this event

5 November 2008: CAD for Electromagnetic Devices, at Rolls Royce plc, Derby


Professor Quentin Pankhurst, Director of The Royal Institution’s Davy-Faraday Research Laboratory, will give a lecture on the Laboratory’s current work and future direction - Healthcare Biomagnetics: a New Age for Magnetic Therapy. Ever since Mesmer enthralled Europe during the Age of Enlightenment, “magnetic healing” has had many colourful champions all too ready to proclaim the amazing powers of magnetism. No less amazing though is the current revolution in healthcare biomagnetics, all of which is based on the solid ground of cross disciplinary innovation. In this lecture the field will be reviewed, with particular attention being given to the sensing, moving and heating of magnetic non-particles in the human body. A number of diagnostic and therapeutic medical applications will be discussed, including a biomagnetometer that is currently being tested by cancer surgeons, and an actuator for the targeted treatment of cardiovascular disease. Professor Pankhurst’s lecture will be complemented by an afternoon programme - Frontiers of Medicine: New and Emerging Roles for Biomagnetics - by four international speakers from the forefront of both academic and industrial biomagnetic research. from 1500 REGISTRATION/COFFEEChairman: Dr Chris Maddison, Cummins Generator Technologies 1530 WELCOME/INTRODUCTION FRONTIERS OF MEDICINE: NEW AND EMERGING ROLES FOR BIOMAGNETICS 1540 Medical Diagnostics Based on Magnetic Nanoparticles, Professor Dr Menno W J Prins, Philips Research, The Netherlands1610 Localised Nucleic Acid Delivery using Magnetic Nanoparticles and Magnetic Force, Dr Christian Plank, Technical University Munich, Institute of Experimental Oncology, Germany 1640 Magnetic Microbubbles for Localised Ultrasound Imaging and Therapy, Dr Eleanor Stride, University College London, Department of Mechanical Engineering1710 Magnetic Nanoparticles as MRI Contrast Agents, Dr Nguyen Thanh, University of Liverpool, Department of Chemistry and School of Biological Sciences1740 INTERVAL: TEA/COFFEE1830 22ND EWING LECTURE: HEALTHCARE BIOMAGNETICS: A NEW AGE FOR MAGNETIC THERAPY, Prof Quentin Pankhurst, Director of the Royal Institution’s Davy-Faraday Laboratory2000 DENNIS HADFIELD MEMORIAL PRIZE AWARD2015 BUFFET SUPPER2200 END

4 February 2009: Noise in Electrical Machines, at Cardiff University Noise is a major concern to the designers and users of electrical machines. The sources of noise in electromagnetic cores include the effects of magnetostriction and Maxwell forces between laminations. Many factors are known to affect the acoustic noise generated by these cores including stress, magnetisation conditions and mechanical resonance but the relationship between material properties, building factors and noise in the electrical machine is not well understood. The magnetostriction of materials can now be characterised in the laboratory under simulated conditions but standardisation of these measurements is still some way from being achieved. This seminar aims to explore the issue of acoustic noise in electromagnetic and electromechanical machines: its causes and mitigation in transformer, inductor and rotating machines and the implications for machine builders particularly with respect to the environmental constraints within which they must now operate.

19 March 2009: Advanced Functional Materials, at National Physical Laboratory, Teddington Continued advances in fabrication and lithography techniques make it possible to produce novel material structures that have no natural equivalent. These artificial structures exhibit novel properties that offer exciting opportunities in areas such as sensors, high frequency electronics and quantum computing. The complex nature of the structures requires a multiphysics approach to the measurement of their properties and this seminar will bring together experts from a number of disciplines. Talks that cover aspects of the magnetic, dielectric and piezoelectric behaviour as well as coupled behaviour will be given. Visits to NPL laboratories involved with developing measurement methods for these unique properties will be available. The seminar aims to provide both an academic and industrial perspective on the following issues amongst others: novel magnetic, dielectric and multiferroic materials; new measurement techniques and applications such as spintronics.

2 April 2009: More Electric Aircraft, at University of Bristol

9 December 2008: 22nd Ewing Lecture - Healthcare Biomagnetics: a New Age for Magnetic Therapy

Professor Quentin Pankhurst at The Royal Society, London

UKMAG forthcoming seminars contd...

Further details and programmes for the above events will appearon the Society’s website when finalised: www.ukmagsoc.org

If you would like to be considered for presenting at one of these events, please contact [email protected]


CHAIRMANDr Chris Maddison, Cummins Generator Technologies, tel: +44 (0)1780 686203, [email protected] VICE CHAIRMANStuart Eaton, QinetiQ Ltd Farnborough, tel: +44 (0)1252 397409, [email protected] Alex Michaelides, Vector Fields Ltd, tel: +44 (0)1865 854932, [email protected] Greaves, Hoganas GB Ltd, tel: +44 (0)1732 377726, [email protected] John Cullen, Rolls Royce plc, tel:+44 (0)1332 260033, [email protected] Dr Robin Cornelius, Hirst Magnetic Instruments Ltd, tel: +44 (0)1326 372734, [email protected] Kennedy, Less Common Metals Ltd, tel: +44 (0)151 652 9747, [email protected] Dr Ernie Hill, University of Manchester, School of Computer Science, tel: +44 (0)161 275 4552, [email protected]

Graham Kemp,TRW Conekt, tel: +44 (0)121 627 3590, graham.kemp@ trw.comDr Michael Hall, National Physical Laboratory, tel: +44 (0)20 8943 7189, [email protected] Glynn Atkinson, University of Newcastle-upon-Tyne, School of Elec, Elec & Computer Eng, tel: +44 (0)191 222 5699, [email protected] Chris Riley, Magnet Applications Ltd, tel: +44 (0)1442 875009, [email protected] Philip Anderson, Wolfson Centre for Magnetics, Cardiff University, tel: +44 (0)29 2087 5936, [email protected] Jonathan Sturgess, AREVA T & D Technology Centre, tel: +44 (0)1785 786519, [email protected] Genhua Pan, University of Plymouth, School of Elec, Comm & Elec Eng, tel: +44 (0)1752 232603, [email protected] Andy Williams, University of Birmingham, Dept of Metallurgy & Materials, tel: +44 (0)121 414 3959, [email protected]

UKMAG Management Committee

200815 Oct UKMAG seminar Advanced Electrical Machines through

Materials, TRW Conekt, Solihull: www.ukmagsoc.org27-30 Oct 5th Int Congress of NanoBio & Clean Tech 2008: www.nan-

otechcongress.com5 Nov UKMAG seminar CAD for Electromagnetic Devices, Rolls

Royce plc, Derby: www.ukmagsoc.org10-14 Nov 53rd Conf on Magnetism & Magnetic Materials, Texas, USA:

www.ieeemagnetics.org/2008/nov.htm 19 Nov UKMAG seminar Permanent Magnets in Extreme Environ-

ments, Univ of Birmingham: www.ukmagsoc.org5-13 Dec CISSE 2008, 4th Int Joint Conf on Computer Information and

Systems Sciences and Engineering: www.cisse2008online.org9 Dec UKMAG 22nd Ewing Lecture: Healthcare Biomagnetics: a

New Age for Magnetic Therapy, and afternoon programme: Frontiers of Medicine: New and Emerging Roles for Biomag-netics, at The Royal Society, London: www.ukmagsoc.org

20094 Feb UKMAG seminar Noise in Electrical Machines, Cardiff Uni-

versity: www.ukmagsoc.org9-11 Feb CWIEME New Delhi, India, Exhibition and Conference: info-

[email protected], tel: +44 (0)1202 743906 15-19 Feb TMS 2009 Annual Meeting and Exhibition, San Francisco,

California, USA: [email protected] Mar UKMAG seminar Advanced Functional Materials, National

Physical Laboratory, Teddington: www.ukmagsoc.org2 April UKMAG seminar More Electric Aircraft, University of Bristol:

www.ukmagsoc.org3-6 May IEEE IEMDC 2009, Intl Electrical Machines and Drives Con-

ference, Miami, Florida: www.iemdc2009.org

4-8 May Intermag2009 Conference, Calif, USA: www.intermagconfer-ence.com/intermag2009

11-12 June EMC Europe Workshop - Materials in EMC Applications, Athens, Greece: [email protected], http://emceu-rope2009.iccs.gr

7-9 Sept SMM19, Torino, Italy: TBC10-12 Sept ISEF09, 14 Int Symposium on electromagnetic fields in

mechatronics, electrical and electronic engineering, Arras, France: www.isee.fr/isef09/

22-26 Nov Compumag 2009, Florianopolis,Brazil: www.compumag2009.comDec UKMAG 23rd Ewing Event: www.ukmagsoc.org

201017-21 Jan Joint MMM/Intermag Conference, Sacramento, USA: www.

magnetism.org/futureconf.htmlTBC 11th Int Workshop on 1&2 Dimensional Magnetic Measure-

ment of Testing (1&2DM), Oita, Japan: details TBCDec UKMAG 24th Ewing Event: www.ukmagsoc.org

201112-15 July Compumag 2011, Sydney, Australia: details TBCDec UKMAG 25th Ewing Event: www.ukmagsoc.org

DATES FOR YOUR DIARY

You are invited to send details of appropriate events for inclusion in Dates for your Diary in future issues of Magnews - for the interest and benefit of Magnews readers

UK Magnetics Society, Grove Business Centre, Grove Technology Park, Wantage, Oxon OX12 9FA, UKtel: +44 (0)1235 770652 fax: +44 (0)1235 772295 email: [email protected] www.ukmagsoc.org

Editor-Magnews: Jane Ward, UK Magnetics SocietyEditorial Committee: Chris Maddison, Cummins Generator Technologies Stuart Eaton, QinetiQ Limited Graham Kemp, TRW Conekt


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