Proceedings of the NATO Advanced Research Workshop on `Tailoring of High Temperature Properties of Si3N4 Ceramics', Schloß Ringberg/Munich, Germany, October 6--9, 1993

The nitrides and carbides of boron and silicon are proving to be an excellent choice when selecting materials for the design of devices that are to be employed under particularly demanding environmental and thermal con- tions. The high degree of cross-linking, due to the preferred coordination numbers of the predominantly covalently bonded constituents equalling or exceeding three, lends these non-oxidic ceramics a high kinetic stability, and is regarded as the microscopic origin of their impressive thermal and mechanical durability. Thus it does not come as a surprise that the chemistry, the physical properties and the engineering of the corresponding binary, ternary, and even quaternary compounds have been the subject of intensive and sustained efforts in research and development. In the five reviews presented in the volumes 101 and 102 of "Structure and Bonding" an attempt has been made to cover both the essential and the most recent advances achieved in this particular field of materials research. The scope of the individual contributions is such as to address both graduate students, specializing in ceramic materials, and all scientists in academia or industry dealing with materials research and development. Each review provides, in its introductory part, the chemical, physical and, to some extent, historical background of the respective material, and then focuses on the most relevant and the most recent achievements.

A comprehensive overview of recent developments in the field of non-oxide ceramics with special emphasis placed on the combustion synthesis of group I-VI nitrides and oxynitrides. To ensure the widest possible perspective, the authors are experts in academia, industry, or government research, and each chapter discusses different synthetic methods and process parameters, as well as important material properties and applications. The result is invaluable reading for researchers and practitioners in the industry as well as those looking for an introduction to the field. It is equally of great interest to chemists and materials scientists as well as engineers working in the area of inorganic and solid-state chemistry, structural and functional materials, catalysis, metallurgy, and electrochemistry.

In this book, improvements in the heat resistance of silicon nitride (Si3N4) ceramics using grain boundary control and in plasticity at high temperatures using grain size control in order to reduce the cost of shaping Si3N4 are described. The heat resistance of Si3N4 is improved by mixing a slight amount of sintering additive as an impurity into the original material powder. The author presents his findings on the high heat resistance of Si3N4. The author also develops a new fabrication method for Si3N4 nano-ceramics that produces high plastic formability. The method developed offers two improved points in grinding and sintering processes. The author found that the plastic formability of Si3N4 nanoceramics is dependent on load stress; the results of his research are detailed in this book.

Several ceramic parts have already proven their suitability for serial application in automobile engines in very impressive ways, especially in Japan, the USA and in Germany. However, there is still a lack of economical quality assurance concepts. Recently, a new generation of ceramic components, for the use in energy, transportation and environment systems, has been developed. The efforts are more and more system oriented in this field. The only possibility to manage this complex issue in the future will be interdisciplinary cooperation. Chemists, physicists, material scientists, process engineers, mechanical engineers and engine manufacturers will have to cooperate in a more intensive way than ever before. The R&D activities are still concentrating on gas turbines and reciprocating engines, but also on brakes, bearings, fuel cells, batteries, filters, membranes, sensors and actuators as well as on shaping and cutting tools for low expense machining of ceramic components. This book summarizes the scientific papers of the 7th International Symposium "Ceramic Materials and Components for Engines". Some of the most fascinating new applications of ceramic meterials in energy, transportation and environment systems are presented. The proceedings shall lead to new ideas for interdisciplinary activities in the future.

Describes the structure and mechanics of a wide range of cellular materials in botany, zoology, and medicine.