Fibrous composites in structural design

Fibrous composites in structural design

world. And I have a plea. I do ask the author to consistently distinguish between the singular and plural of the noun 'medium'. Confusion can arise wh...

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world. And I have a plea. I do ask the author to consistently distinguish between the singular and plural of the noun 'medium'. Confusion can arise when singular and plural are conflated and it is for that reason that a clear distinction between singular and plural is possible in languages fit for scientific discussion, such as Latin, English and Chinese.

A. Kelly

Advances in composite materials Edited by A.R. Bunsell et al

Pergamon Press L td (1980) price £85. O0 Economic recession has had little effect to date upon the level of effort directed towards the development of fibre composites judging by the spread of papers and attendance at the Third International Conference on Composite Materials which was held in Paris during August of last year. Some 140 papers were presented and virtually all of them are contained within these two volumes. There was a wide spread of topics covered by the papers and as a result these two volumes give a reasonably well balanced view of the composites scene and they are therefore a useful reference for current developments. At a conference where papers are presented in parallel sessions one's overall view is clearly strongly influenced by the papers attended or perhaps I should say that one hoped to attend, since we still seem to have session chairmen who move papers forward when one is cancelled and it is possible to turn up to a different paper to that chosen. However the overall message of the conference seemed to be that optimism abounds for composites in aerospace and car industries and both are expected to become very large users by the later 1980s. New generation commercial aircraft may well top the bill. Turning now to the various sessions all one can hope to do in a review of this kind is to comment on a few. It is interesting to see that the subject of composite integrity under stress and stress plus environment is commanding greater interest and that in the United States many of the design and analysis experts are now applying themselves to the prediction of delamination and cracking phenomena that occur prior to ultimate failure in composites. Furthermore, the number of papers on environmental ageing and corrosion aspects almost reached double figures. Apart from the above comments, the sessions on fatigue and fracture, mechanical and physical properties, design and analysis and testing indicate further progress in our general understanding of composites and make interesting reading for those who have interests in these areas. It is difficult to single out any particular papers for specific attention. Yet once again one is impressed by the overwhelming domination of the design and analysis field by American engineers and scientists. The session on non-destructive testing and control of structures had several papers on the use of acoustic emission for assessing composite behaviour but I think the feeling still is that this technique has some way to go before it can be used simply, in evaluating the quality or mechanical degradation of laminates. Other sessions dealt with metal matrix

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composites, joints, aeronautical applications and there was a substantial session on fabrication techniques. An area in which I felt there was a lack of papers, no doubt reflecting the difficulty of the problem, is in assessing the properties and behaviour of matrix materials particularly in polymer composites in which there is now considerable evidence that curing in the presence of fibres often markedly affects the properties achieved, compared with those obtained for bulk polymer material. I should also mention that there was a session on applications covering, for example, the use of GRP in pipes and even violins! Finally, mention should be made of the plenary papers contained in these volumes. The paper by P. Peterson of the Airforce Wright Aeronautical Laboratories USA maps out comprehensively the US approach to composites in aerospace both past, present and future. A further one deals with the all fibre-composite Ford car built in the United States. Professor Menges presented a comprehensive paper on sorption behaviour of composites and S.J. Dastin reviewed design and concepts for composite structures. Finally, S. Antonioli discussed economic aspects of the development of polymer matrix composite materials. At a price of £83.00 for the two volumes, it is unlikely that many will be purchased out of personal resources but in view of the comprehensive coverage, I would expect to find them in most reference libraries. 3,E Bailey

Fibrous composites in structural design Edited by Lenoe, Oplinger and Burke

Plenum Press (1980) price $85.00 A number of edited volumes have appeared on the topic of the design of structures with fibrous composites. They are usually aimed at specific fields. This volume is the fourth conference on fibrous composites in structural design and succeeds the first three conferences on flight velucle design sponsored by the US Air Force and by NASA. This fourth conference held in San Diego in November 1978 was different from the first three in being sponsored by the US Army, Navy and Air Force together with NASA and being the first of such conferences to give attention to non aerospace applications. Aerospace applications figure largely, in particular the AV8B and a number of launch vehicles structures and helicopter rotor blades but in addition areas such as military bridge building, fly wheel storage systems and ship and surface vessel components are described. Problems of durability and reliability figure in the book with a number of papers on the prediction of failure processes by a mixture of observation and computer calculations of what is likely to occur under stress. In addition there are sections on environmental degradation, foreign object damage and the kinetics of moisture diffusion. There is an interesting analysis by Burke of whether advanced composite materials can compete in the automotive market. The book is unlikely to appear on the personal shelves of many workers and much of what is in it is available elsewhere. However, it is a useful record of the conference and it is perhaps a pity therefore that a number of the important summarizing papers given at the conference do not appear.

A. Kelly COMPOSITES . OCTOBER 1981