itb (institut teknologi brunei) engineering materials introduction pce1enm 2013
DESCRIPTION
ITB (Institut Teknologi Brunei) Engineering Materials Introduction PCE1ENM 2013TRANSCRIPT
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Chapter 1 -
Before we begin……..DGH needed a crown
Chapter 1 -
• Get into groups of 3-4 students and think:
What properties does DGH require in the
material used for his crown?
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Chapter 1 -
A tooth “fit for a lecturer”
Properties:
Water proof
Resistant to chemical attack
Durable for duration of human lifespan
Surface feel same as a normal tooth
As “ard” as a tooth
Tastes like a tooth
Smells like a tooth
Doesn’t attract “stuff” onto its surface
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Chapter 1 - 4
Engineering Materials
Course Objective...
Introduces fundamental concepts in MaterialsScience and Engineering
You will learn about:• material properties / structure
• how properties dictate structure
• how processing can change structure
This course will help you to:• use/design materials properly
• realise new design opportunities with materials
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Chapter 1 - 5
LECTURES
Lecturer: David Hassell
Time (during Ramadan):
Wed 09:45 – 11:00 and Thurs 11:00 – 12:00
Activities:
• Present new materials/lecture notes
• Lectures/ Example classes
• Group work and discussions
Chapter 1 - 6
ASSESSMENT
Degree[PCE1ENM]
Higher Diploma[PCE1ENH]
In-class test 10 10
Report 10 20
Assessed
exercises
10 10
Exam 70 60
Coursework will be mainly the same, but marked
differently.
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Chapter 1 - 7
Chapter 1 - Introduction to Materials Science and Engineering
• What is materials science/eng?
• Why should we know about it?
• Materials drive our society
– Stone Age
– Bronze Age
– Iron Age
• Now?
– Silicon Age?
– Polymer Age?
Chapter 1 -
Student exercise:
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Split into groups of 4:
Task: Think of the products and materials that we use today. List down ten items that we use regularly today (2013) that we didn’t 10 years ago (2003).
We’ll then go through the list of each group and see what products are everyday items
Q: What materials make these products possible? Are they new, or are they old materials?
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Chapter 1 -
Student exercise:
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Opic fibre cables for phone/internet
Clever phone
“A* grade” television
Thunderbolt
Digital camera
James Bond style camera contact lens
Google everything!
3D cinema glasses
e-cigar
Hybrid (ugly) car
Chapter 1 -
Examples cont….:
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3D printer
Blue ray DVD’s & “stuff”
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Chapter 1 - 11
Age Period Tools
Stone
age
Palaeolithic Handmade tools and objects found in nature –
cudgel, club, sharpened stone, chopper,
handaxe, scraper, spear, harpoon, needle,
scratch awl
Mesolithic
(other name
epipalaeolithic)
Handmade tools and objects found in nature –
bow and arrow, fish – basket, boats
Neolithic Handmade tools and objects found in nature –
chisel, hoe, plough, yoke, reaping-hook,
grain pourer, barley, loom, earthenware
(pottery) and weapons
Bronze Age Copper and bronze tools, potter's wheel
Iron Age Iron tools
Historical Perspective
Chapter 1 - 12
Materials Science vs Engineering
Materials science – investigating the relationships that exist between the structures and properties of materials
Materials engineering – designing or engineering the structure of a material to produce a pre-determined set of properties
Material scientist - develops/synthesizes new materials
Material engineer – creates new products/systems using existing materials and/or develops techniques for processing materials
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Chapter 1 - 13
Material Structures
• Structure relates to the arrangement of its internal components
• Subatomic structure - electrons, protons and neutrons
• Atomic structure - encompasses the organisation of atoms or molecules relative to one another
• Microscopic structure - large groups of atoms that are normally agglomerated together, that can be viewed under the microscope.
• Macroscopic structures – very large groups of atoms that can be viewed by the naked eye
Chapter 1 - 14
Material Properties
1. Mechanical – elastic modulus, strength
2. Electrical – electrical conductivity, constants
3. Thermal – thermal conductivity, heat capacity
4. Magnetic – response of a material in a
magnetic field
5. Optical – refractive index, reflective index
6. Deteriorative – chemical reactivity
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Chapter 1 - 15
Material Processing and Performance
Aluminum oxide may be transparent, translucent, oropaque depending on
the material structure.
single crystalpolycrystal:low porosity
polycrystal:high porosity
Chapter 1 - 16
Why study Materials Sc/Eng?
• Important in the investigation and design
of materials
• Selecting the right material for an
application
• Economics of material selection and
utilisation
• Basically, an engineer with the above
knowledge would be one who is proficient
and confident when making selection or
designing materials
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Chapter 1 - 17
Types of Materials
• Metals:
– Strong, ductile
– high thermal & electrical conductivity
– opaque, reflective.
• Polymers/plastics: Covalent bonding ���� sharing of e’s
– Soft, ductile, low strength, low density
– thermal & electrical insulators
– Optically translucent or transparent.
• Ceramics: ionic bonding (refractory) – compounds of metallic & non-metallic elements (oxides, carbides, nitrides, sulfides)
– Brittle, glassy, elastic
– non-conducting (insulators)
Chapter 1 - 18
1. Metals
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Chapter 1 - 21
Beverage containers:
what are adv and disadv of each?
Aluminium cans
Plastic bottles
Glass bottles
Chapter 1 -
Beverages – why la?
• Plastic fantastic
• Cheap, light, can
be
reused/recycled,
ductile,
transparent, inert?
• Mundane Metal
• Cheap (ish),
recyled, light,
ductile, shiny, inert
• Gorgeous glass
• Expensive
(relatively), heavy,
inert, brittle,
recyled
(elsewhere), cool22
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Chapter 1 - 23
Advanced Materials
Advanced materials – materials used in high or advanced technological applications
What do we mean by high technology?
A device or product that operates / functions using relatively intricate and sophisticated principles
Examples?
Electronic equipment (camcorders, CD/DVD players, etc), computers, fibre-optic systems, spacecraft, military, rocketery, etc
Chapter 1 - 24
Classification of Advanced Materials
1. Semiconductors
2. Biomaterials
3. Smart materials
4. Nano-engineered materials
3 and 4 are known as “materials of the
future”
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Chapter 1 - 25
1. Semiconductors
• Electrical properties that are intermediate
between the electrical conductors and the
insulators
• Example semiconductor materials – silicon,
germanium
• They are extremely sensitive with the
presence of impurities, even at minute
concentrations (doping)
• Semiconductors have totally revolutionised
the electronics and computer industry
Chapter 1 - 26
2. Biomaterials
• Employed in components planted into the
human body for replacement of diseased or
damaged body parts
• These materials must not produce toxic
substances and must be compatible with
body tissues
• All the basic materials – metals, ceramics,
polymers, composites, etc may be used as
biomaterials
• Following is an example of biomaterial
utilisation in artificial hip replacements
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Chapter 1 - 27
Example – Hip Implant
• With age or certain illnesses joints deteriorate.
Particularly those with large loads (such as hip).
Chapter 1 - 28
Hip Implant
• Requirements
– mechanical
strength (many
cycles)
– good lubricity
– biocompatibility
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Chapter 1 - 29
Hip Implant
Chapter 1 - 30
Hip Implant
• Key problems to overcome
– fixation agent to hold
acetabular cup
– cup lubrication material
– femoral stem – fixing agent
(“glue”)
– must avoid any debris in cup
Femoral
Stem
Ball
Acetabular
Cup and Liner
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Chapter 1 - 31
3. Smart materials
• Smart/ Intelligent materials – group of new state-of-the-art materials
• Are able to sense changes in their environments and then respond to these changes in pre-determined manners (traits that are found in living organisms)
• Components of smart materials –traditional materials (metals, ceramics, polymers) + sensors (piezoelectric ceramics, magnetostrictive materials and electrorheological/magnetorheological fluids, etc)
Chapter 1 - 32
Example – Helicopters
• A smart material which can reduce aerodynamic cockpit noise that is created by the rotating rotor blades
• Piezoelectric sensors inserted into the blades monitor stresses and deformations; feedback signals from these sensors are fed to a computer-controlled adaptive device, which generates noise-canceling anti-noise
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Chapter 1 - 33
4. Nano-engineered materials
• Materials which are produced by
arranging individual atoms (at the nano
level) – provides us with the opportunity
to design new materials, with new
mechanical, electrical, magnetic and
other properties
• A “bottom-up” approach
• One important material – the carbon
nanotube
Chapter 1 - 34
Example – Carbon Nanotubes
3D model of three types
of single-walled carbon
nanotubes.
This animation of a
rotating Carbon
nanotube shows its
3D structure.
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Chapter 1 - 35
1. Pick Application Determine required Properties
2. Properties Identify candidate Material(s)
3. Material Identify required Processing
Processing: changes structure and overall shape
ex: casting, sintering, vapor deposition, dopingforming, joining, annealing.
Properties: mechanical, electrical, thermal,magnetic, optical, deteriorative.
Material: structure, composition.
The Materials Selection Process