Developments in reinforced plastics—5

Developments in reinforced plastics—5

Book reviews 75 differential straining between the adhesive and laminate is enhanced so that adhesive stresses are increased locally leading to prem...

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differential straining between the adhesive and laminate is enhanced so that adhesive stresses are increased locally leading to premature failure. So a careful balance between adhesive and laminate properties must be chosen. To improve the efficiency of joints, the shape of the end of the overlap region requires careful consideration. Double lap joints, being symmetrical, remove some of the bending problems. Tapering the ends of the lapping piece may reduce discontinuities. Scarfed and stepped lap joints are also described. These are more complicated to design and manufacture but can be highly efficient. The two chapters on design written by Hart-Smith reflect present-day practice in the aerospace industry where high safety standards are paramount. The methods can however be applied to all structural joints whatever their fields of application. This book gives a good review of the relevant fields and is a must for anyone concerned with composite joint design and manufacture, or as a background to follow later results in this field. K. J. Pascoe Developments in Reinforced Plastics---5. Edited by G. Pritchard. Elsevier Applied Science Publishers, London, 1986. Price £37.00. This publication is the fifth volume of the Series and is concerned mainly with processing and fabrication of high performance composites. It is considerably more than a review of techniques for the production of fabricated parts. Rather, different aspects of materials science related to the processing of polymer-based composites have been treated in some depth by leading scientists in the field. The result is an interesting collection of papers, generally well written, but not sufficiently coordinated. In the first chapter, Cattanech and Cogswell present a very extensive review of the properties and processing of carbon-fiber-reinforced polyether ether ketone (PEEK) composites based on their deep knowledge of the subject. It is a very descriptive article with informative pictures but few experimental data. In contrast, the second chapter by Landman describes in detail the chemistry and the processing ofpolymides and bismaleimides used in composites and as sealants and adhesives. It is packed with information and experimental data on commercial materials and represents an interesting reference paper for scientists and engineers working in the area. The third chapter, a review of prepreg technology written by Wiedenman and Rothe, is mainly concerned with electrical grade laminates. The analysis of epoxy cure-kinetics is oversimplified and represents only an approximation of actual behaviour, and the remainder of the chapter is very

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Book reviews

descriptive. In the next chapter, however, a more detailed analysis of the curing processes of acetylene terminated resins is presented by C. Y. C. Lee. The cure kinetics and the processing of this new class of materials for high temperature composites are presented and the dependence of mechanical properties on cure is discussed. Chapter 5, prepared by Apicella, deals expressly with the effect of chemo-rheology on epoxy resin properties. A detailed literature survey is offered and basic polymer chemistry and physics are used to develop a model for predicting the change of viscosity with temperature for a reactive system. In Chapter 6, D. E. Kranbuchel discusses very clearly the use of three dielectric parameters, which characterize ionic and dipolar molecular properties of a material, for monitoring nondestructively the cure of high-performance composites during processing as a means of quality control. Experimental data for both thermoplastic and thermoset composites are presented. In the next chapter, D. P. Bashford briefly reviews the technology for joining composite parts. Both mechanical fastening and adhesive bonding techniques are described and some design parameters are discussed. In the last chapter, T. Hirai analyses theoretically the rheology of carbon fiber prepregs and presents numerical results obtained under different processing conditions. In conclusion, this book consists of 7 chapters with different levels of quality and scientific depth and, as pointed out in the preface, no attempt has been made to provide a comprehensive survey of the science and technology of the processing of reinforced plastics. Some of the chapters, however, are very well organised and contain useful information. The book is a valuable addition to the library shelves of scientists and engineers working in the composite field. L. Nicolais