simple fluids is bound to be of only academic interest.

The final three chapters concern special processes, the particular considerations involved in the grinding of hard refractory and ceramic materials and precision finishing methods - these are the areas of most active current research and development and therefore contain the most recent references in the literature. The development of both the semiconductor industry and of a variety of surface coating and engineering techniques has refocused attention of those abrasive machining processes in which the abrasive element is free rather than embedded in a wheel or grinding element. Although the investigation of lapping, honing, polishing and buffing has a long pedigree there is even now no unanimity about the removal and deformation mechanisms dominant in each. The introduction of novel features and geometries is leading to several innovative production routes for the manufacture of machine components in materials

otherwise almost impossible to form at economically realistic removal rates. By about 1970 grinding accuracies down to about 1 micron had been achieved; although this has improved by about a factor of 10 in current best practice, the demands of the developing field of nanotechnology, especially in the optical and electronic fields, require further significant increases in precision. In ductile materials single point diamond turning can produce results of the sort required but makes great demands on both the accuracy and stiffness of ‘the machine tool on which the process is carried out and on the sharpness of the cutting edge-it is suggested that single stone diamonds can be polished to a tip radius of about 10 nm which means that it should be possible to machine in a conventional chip- forming sense at depths of cut down to about 50 nm. At these sorts of length-scales the usual assumptions of homogeneity and isotropy of the workpiece also become questionable and the

A Guide to Surface Engineering Terminology

PII: SO301-679X(96)00053-9

This book stems from a study carried out by a team of 12 international experts set up by the International Federation for Heat Treatment and Surface Engineering. This team was charged with defining the main terms used in surface engineering technologies and met on several occasions between 1987 and 1990 to devise a structured set of terminology definitions.

It is perhaps disappointing that the names of the people on the working party are not recorded anywhere within this volume, although one can appreciate that many of the definitions originally

Institute of Materials, ISBN 09 01716 642, f40

proposed have not been used or may have been changed by the editors. Indeed the editors are to be congratulated on having avoided a straight listing of definitions. Instead the text contains narrative which elucidates concepts and interrelationships between processes in greater detail than a mere dictionary of terminology would achieve. Furthermore, line drawings and photographs have been used to illustrate particular concepts. This makes the book more readable and informative than would otherwise have been the case.

Nevertheless, in any book which aspires to cover a diverse subject area comprehensively, there are a few entries which may be considered rather trivial or which

structural aspects of dislocation activity become rather different from those at more conventional scales; these can be explored through the techniques of molecular dynamics, though, as Shaw comments, those simulations insufficiently large to encompass some form of defect structure will be of limited use.

There is a lot of information, judgement and data in this volume which is produced to the sort of standards of printing, paper and illustration one would expect from this OUP Series in Advanced Manufacture; it will not revolutionize grinding practice but should prove an enormously valuable compendium of wisdom for those concerned with the longer term development of this important manufacturing technology.

John Williams Cambridge University

Department of Engineering Cambridge, UK

could equally well be found in a normal dictionary (e.g. ‘cleaning’ is defined as ‘any method of removing surface contamination’). The book is much stronger and really comes into its own on more recent terms, whose definitions cannot be found elsewhere. For many of these the text would have benefited from more follow-up references, allowing the reader to discover where further information could be found. Likewise, more cross-referencing is needed in a number of areas. particularly since no alphabetical index is included at the back. For example ‘cleaning’ is not cross-referenced to ultrasonic degreasing or vapour degreasing, which are defined further. Similarly ‘abrasive blast cleaning’ and ‘grit blasting’ are

460 Tribology International Volume 30 Number 6 1997

separately defined and not cross- referenced.

Ther: are some idiosyncrasies in the text. These may have arisen partly because the editors have tended to emphasize their special fields of interest. For example, one individual is given a citation; that is Bernard Berghaus. Whilst he and l.he companies he represented were clearly extremely influential in vacuum plasma-based processes, it seems odd that he alone should have biographical details recorded when one considers all of the pioneering individuals and companies involved in coating and treatment technologies.

It would be difficult not to miss some terms in a book of this kind, especially when these may have recently come to the fore. However there are some expressions and words in increasing usage which are notable by their absence. For example ‘hybrid’ coatings and treatments and ‘functionally graded’ coatings and materials are now widely researched, and (in the latter case) ever1 have whole conferences devoted to them. Neither is met tioned here.

There are also a few examples of inaccuracies or misconceptions in the text, for example fatigue failure is defined in terms of rolling contact fatigue, then a gear tooth subjected to root (i.e. bending) fatigue is taken as an example. Process descriptions also, partly due to the need for brevity and succinctness, sometimes convey incorrect information. For example in discussing the supported glow discharge plasma, increasing the current density at the substrate is said to improve the coating adhesion and the throwing power of the process. This is most certainly not necessarily true. Increased ion bombardment can lead to increased stresses and poorer effective adhesion. Also many enhanced plasma devices (such as unbalanced magnetrons) are actually highly directional in terms of the ion flux and thus can result in reduced throwing power. Also, in regard to such processes, terms such as ‘plasma enhancement’ and ‘ionization efficiency’ are commonly used but not defined here. Of course some terms and acronyms are often used with

High Efficiency Deep Grinding Taghi Tawakoli

PII: SO301 -679X(96)00050-3

Grinding is one of the basic manufacturing processes used to produce surfaces with required roughness and dimensional precision. A number of new grinding methods such as creep feed grinding, ultrasonic assisted grinding, energy beam assisted grinding, magnetic fluid grinding, triblochemical grinding which have been developed over the years are welcome additions to conventional reciprocating grinding. The current development efforts in this area are directed to improve efficiency of grinding which is especially important in the case of very hard

Mechanical Engineering Publications, Len- don, ISBN 0 85298 820 6, 1993, 14lpp

and brittle materials such as ceramics.

High efficiency deep grinding, the theme of the book, departs significantly from practices of conventional grinding. This is because the results of theoretical and applied research show that increasing individual parameters such as wheel speed, depth of cut or specific removal rate results in the increase of grinding temperature which, in turn, can cause damage to the work-piece. However, these parameters are usually set at a very high level in high efficiency deep grinding; nevertheless the grinding temperatures are lower than in

different meanings by different groups. In that case it is best to define both meanings, or the most common. DLC is a case in point, which most often is Iused to mean ‘diamond-like-carbon’ rather than ‘diamond-like-coating’ as defined here. In the particular definition made, the authors describe the coating as being very hard; in practice however, such films can possess a range of properties, including more elastic or even polymeric characteristics. In this regard it would perhaps be most appropriate to define also the terminologies ‘amorphous hydrogenated carbon’ (a-C:H) and ‘metal-carbon’ (M-C:H) films, which are probably the most widely used coatings of this type in industry.

Notwithstanding these criticisms the editors have effectively met what must have been a most difficult challenge to produce a text which will be helpful to those active in industry and research who deal with surface engineering processes.

Allan Matthews

conventional grinding. For that reason previous findings on conventional grinding cannot be used in high efficiency deep grinding. Therefore, machine and tool requirements in high efficiency deep grinding are also different from those applicable to conventional grinding.

This book is a translation from German. It describes and discusses the technological requirements and theoretical fundamentals of high efficiency deep grinding. The role of machine settings and their influence on the process of material removal is considered and explained. Also, the guidance for practical applications of the

Tribology International Volume 30 Number 6 1997 461