V. I. MATKOVICH During the meeting of the International Symposium on Boron held in October, 1972 in Tbilisi, U.S.S.R., the idea was proposed to assemble a review of boron and refractory borides by the specialists present. The advantages of such a work were immediately apparent. Such diverse applications of borides as in protective armor, nuclear reactors, coat ings, reinforcement, etc. can hardly all be presented in sufficient detail by a single author. On the other hand it was also recognized that with so much specialization, some areas of interest may not be covered. Within the last decade or two a number of areas have been developed in which the use of refractory borides is growing and improvements are being actively explored. Thus, a number of borides have considerable potential as reinforcing material for plastics or light metals, though only boron fibers have been firmly established up to the present. Ap plication of flakes and films for two-dimensional reinforcement appears attractive, although the high cost of materials and development repre sents a considerable barrier. A number of borides have been used to manufacture lightweight protec tive armor. In this area relatively fast changes seem to be taking place as improvements in performance and weight are made. Boron carbide has found considerable use in this application and new developments exploit the light weight of beryllium borides.

Carbides, nitrides and borides are families of related refractory materials. Traditionally they have been employed in applications associated with engineering ceramics where either high temperature strength or stability is of primary importance. In recent years there has been a growing awareness of the interesting electrical, thermal and optical properties exhibited by these materials, and the fact that many can be prepared as monolithic ceramics, single crystals and thin films. In practical terms carbides, nitrides and borides offer the prospect of a new generation of semiconductor materials, for example, which can function at very high temperatures in severe environmental conditions. However, as yet, we have only a limited understanding of the detailed physics and chemistry of the materials and how the preparation techniques influence the properties. Under the auspices of the NATO Science Committee an Advanced Research Workshop (ARW) was held on the Physics and Chemistry of Carbides, Nitrides and Borides (University of Manchester, 18-22 September, 1989) in order to assess progress to date and identify the most promising themes and materials for future research. An international group of 38 scientists considered developments in 5 main areas: The preparation of powders, monolithic ceramics, single crystals and thin films; Phase transformations, microstructure, defect structure and mass transport; Materials stability; Theoretical studies; Electrical, thermal and optical properties of bulk materials and thin films.

A survey of current research on a wide range of carbide, nitride and boride materials, covering the general issues relevant to the development and characterisation of a variety of advanced materials. Topics include structure and electronic properties, modeling, processing, high-temperature chemistry, oxidation and corrosion, mechanical behaviour, manufacturing and applications. The volume complements more specialised books on specific materials as well as more general texts on ceramics or hard materials, presenting a survey of materials research as a key to technological development. After decades of research, the materials are being used in electronics, wear resistant, refractory and other applications, but numerous new applications are possible. Roughly equal numbers of papers cover theoretical and experimental research in the general field of materials science of refractory materials. Audience: Researchers and graduate students in materials science and engineering.

Carbide, Nitride and Boride Materials Synthesis and Processing is a major reference text addressing methods for the synthesis of non-oxides. Each chapter has been written by an expert practising in the subject area, affiliated with industry, academia or government research, thus providing a broad perspective of information for the reader. The subject matter ranges from materials properties and applications to methods of synthesis including pre- and post-synthesis processing. Although most of the text is concerned with the synthesis of powders, chapters are included for other materials such as whiskers, platelets, fibres and coatings. Carbide, Nitride and Boride Materials Synthesis and Processing is a comprehensive overview of the subject and is suitable for practitioners in the industry as well as those looking for an introduction to the field. It will be of interest to chemical, mechanical and ceramic engineers, materials scientists and chemists in both university and industrial environments working on or with refractory carbides, nitrides and borides.

Composite materials, often shortened to composites, are engineered or naturally occurring materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct at the macroscopic or microscopic scale within the finished structure. The aim of this book is to provide comprehensive reference and text on composite materials and structures. This book will cover aspects of design, production, manufacturing, exploitation and maintenance of composite materials. The scope of the book covers scientific, technological and practical concepts concerning research, development and realization of composites.

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