valuable suggestions and constant help during the writing of the book, to Professor P. V. Gel'd for reading the manuscript and mak- ing valuable comments, and also to her colleagues in the Labora- tory for the Technology of Inorganic Compounds in the Institute for Problems in Materials Science of the Academy of Sciences of the Ukrainian SSR, in particular, to G. N. Makarenko, V. B. Fedorus, o. F. Kvas, and A. V. Tkachenko for assistance in planning the book and reading the manuscript. Contents Chapter I The Structure and Physi- chemical Properties of Carbides. . 1 Structures --. . . . . . . . . . . . . . -. -. . --. 1 Thermodynamic and thermophysical properties 22 Electrophysical and magnetic properties . . . . 30 Physicomechanical properties - . . - - . . . . . . 38 Chemical properties . . . . . . ---. . . --. -- 41 Chapter II Methods of Producing Carbides. . . 51 Chapter ITI Carbides of Metals of Group I -. . - 61 Carbides of the alkali metals . . . - . . - . - . . - 61 Carbides of metals of the copper subgroup. - - 66

The first ever book on the applications of fullerenes and nanotubes. World's experts on the industrial use of these new forms of carbon contributes chapters, that are based on lectures given in a large workshop held on February 2001, and expanded thereafter. The contents are intended for those who are interested in the exploration of industrial applications of fullerenes and carbon nanotubes.

The Sixth Army Materials Technology Conference, IICeramics for High Performance Applications-II I-Reliabilityll , was co-sponsored by the Army Materials and Mechanics Research Center and the U. S. Department of Energy, Office of Transportation Programs . The program highlighted all issues relevant to the reliability of ceramics in advanced systems. The conference emphasized programmatic reviews of the major efforts on ceramic gas turbine technology, on an international basis. The conference showed how ceramic design, materials development, materials processing, NDE, and component systems testing are being integrated and iterated in specific engine development programs . Further , the conference promoted inter change among the various technical disciplines working in the advanced turbine and heat engine areas. This volume will join its earlier companions, Ceramics for High Performance A lications (1974), and Ceramics for High Performance Applications-II 1 7 ,in chronicling the rapid progress being made in the applicaton of ceramics to the very demanding service environ ment of gas turbine and piston engines. At the last meeting of this series at Newport, R t, in March 1977, successful high temperature tests of ceramic components in test rigs were described.

During the past ten years, evidence has developed to indicate that seawater convects through oceanic crust driven by heat derived from creation of lithosphere at the Earth-encircling oceanic ridge-rift system of seafloor spreading centers. This has stimulated multiple lines of research with profound implications for the earth and life sciences. The lines of research comprise the role of hydrothermal convection at seafloor spreading centers in the Earth's thermal regime by cooling of newly formed litho sphere (oceanic crust and upper mantle); in global geochemical cycles and mass balances of certain elements by chemical exchange between circulating seawater and basaltic rocks of oceanic crust; in the concentration of metallic mineral deposits by ore-forming processes; and in adaptation of biological communities based on a previously unrecognized form of chemosynthesis. The first work shop devoted to interdisciplinary consideration of this field was organized by a committee consisting of the co-editors of this volume under the auspices of a NATO Advanced Research Institute (ARI) held 5-8 April 1982 at the Department of Earth Sciences of Cambridge University in England. This volume is a product of that workshop. The papers were written by members of a pioneering research community of marine geologists, geophysicists, geochemists and biologists whose work is at the stage of initial description and interpretation of hydrothermal and associated phenomena at seafloor spreading centers.

This volume contains a series of papers originally presented at the Symposium on Polymer Gels organized and sponsored by the Research Group on Polymer Gels, The Society of Polymer Science of Japan and co-sponsored by the Science and Technology Agency (ST A) and MIT , Japan. The Symposium took place at Tsukuba Science City on 18th and 19th September, 1989. Recognized experts in their fields were invited to speak and there was a strong attendance from government, academic and industrial research centers. The purpose of the Symposium was to review the state of the art and to present and discuss recent progress in the understanding of the behavioral properties of polymer gels and their application to biomedical, environmental and robotic fields. Most of the papers and related discussions concentrated on the swelling behavior of hydrogels and chemomechanical systems, both artificial and naturally occurring, in which external stimuli of a physical or chemical nature control energy transformation or signal transduction. The recent great interest in chemomechanical systems based on polymer gels has stimulated considerable effort towards the development of new sensors and actuators, controllable membrane separation processes, and delivery systems in which the functions of sensing, processing and actuation are all built into the polymeric network device. Artificial chemomechanical systems, through the use of environmentally sensitive polymer gels, are emerging as interesting materials for mimicking basic processes previously only confined to the biological world, and commercially viable applications are also foreseen in the not-too-distant future

Conferences have been held in the past on atomic collision phenomena and on the applications of ion beams to semiconductors. However, within the past year it became apparent that there is a growing new area of active research involving the use of ion beams to modify and study the basic properties of metals. As a result a topical conference was organized to bring together for the first time scientists with a wide range of backgrounds and interests related to this field. This book contains the proceed ings of the International Conference on Applications of Ion Beams to Metals which was held in Albuquerque, New Mexico, October 2-4, 1973. Much of the work presented herein represents ideas and concepts which have had little or no previous exposure in the open literature. The application of ion beams to superconducting prop erties for example is quite new, as is the chapter on ion induced surface reactions, which includes primarily oxidation and corrosion studies of implanted materials. These areas, as well as the chapter on implantation alloy formation, indicate important future areas of the application of ion beams to metals. A reading of the chapters on superconductivity and on oxida tion and corrosion can serve to bring one up to date on nearly all the existing information in these areas of the ion beam mod ification of metals. A broad perspective of the oxidation area is given in the invited paper by G. Dearnaley."

The 1984 Cargese Advanced Study Institute was devoted to the study of nuclear heavy ion collisions at medium and ultrarelativis tic energies. The origin of this meeting goes back to 1982 when the organizers met at the GANIL laboratory in Caen, France which had just started accelerating argon ions at 44 MeV per nucleon. We then realized that 1984 should be the appropriate time to review the first results obtained with such new kinds of facilities. The material contained in this volume, presenting many beautiful re sults on nuclei at high excitation, fully confirms this point. Many stimulating exchanges between experts in rather diffe rent fields already took place during the school and we hope that this cross fertilization will lead to further developments. About half of the present volume is also devoted to the field of relativistic heavy ion collisions, which is now expanding rapidly. As an illustration, let us recall that the construction of a 30 on 30 GeV per nucleon collider at Brookhaven has been recognized last year as one cf the major priorities by the US Nuclear Science Advisory Committee. We would like to express our gratitude to NATO for its ge nerous financial support which made this institute possible. We also wish to thank the Institut de Physique Nucleaire et de Physique des Particules (France), the Commissariat a l'energie atomique (France) and The National Science Foundation (USA) for the attribution of travel grants."

Resinography is a strange new word to many people. Like all scientific terms, it is a word coined for a specific purpose: to indicate (in this case) that resins, polymers, and plastics write their own history on the molecular and other structural levels. The word indicates further that anyone trained and equipped to ask the right questions (by means of instruments and techniques) will be able to read that history. That person must have sufficient training and experience to interpret the answers, of course, and he or she needs to have the temperament of a detective. But in the end, as readers of this book will discover, one is able to identify the material, to determine its history of treatment, and to learn much about its possible field of usefulness. Obviously, the resinographer seeks to do the same thing with res ins, polymers, and plastics that the metallographer does with metals and their alloys. Often the investigative techniques and the instru ments, too, are similar, but sometimes they are decidedly different. Perhaps it would be best to say that resinography and metallographyl (and petrography as well) share a common origin, and that origin is deeply rooted in microscopy. The "grandfather" of all three "ographies" was Henry Clifton Sorby (1826-1908),2 who initiated 3 metallography and petrography, and was the first to report on the microstructure of a resin (amber, a natural fossil resin)."

The possibility of initiating chemical reactions by high-intensity laser exci tation has captured the imagination of chemists and physicists as well as of industrial scientists and the scientifically informed public in general ever since the laser first became available. Initially, great hopes were held that laser-induced chemistry would revolutionize synthetic chemistry, making possible "bond-specific" or "mode-specific" reactions that were impos sible to achieve under thermal equilibrium conditions. Indeed, some of the early work in this area, typically employing high-power continuous-wave sources, was interpreted in just this way. With further investigation, however, a more conservative picture has emerged, with the laser taking its place as one of a number of available methods for initiation of high-energy chemical transformations. Unlike a number of these methods, such as flash photolysis, shock tubes, and electron-beam radiolysis, the laser is capable of a high degree of spatial and molecular localization of deposited energy, which in turn is reflected in such applications as isotope enrichment or localized surface treatments. The use of lasers to initiate chemical processes has led to the discovery of several distinctly new molecular phenomena, foremost among which is that of multiple-photon excitation and dissociation of polyatomic molecules. This research area has received the greatest attention thus far and forms the focus of the present volume.

The inspiration for translating this classic text came during a sabbatical year spent at the University of Karlsruhe in 1974. Under the leadership of the late Professor Hans Rumpf, the Institut fUr Mechanische Verfahrenstechnik, Karlsruhe, from the early 1960s onwards, by extensive research and advanced teaching had promoted the discipline of mechanical process technology, a branch of process engineering which had been rather neglected, especially in many chemical engineering depart ments of universities in the English-speaking world. There is a need for texts of this kind, particularly for the more specialized teaching that has to be done during the later stages of engineering courses. This work, which is really a monograph, serves as a concise and compact introduction, albeit at an advanced level, to all those functions of process engineering that have to do with the handling and treatment of particulate matter and bulk solids. Much of this information has previously been scattered around journals and other books and not brought together in one work. Furthermore, Rumpf has emphasized the physical and theoretical foundations of the subject and avoided a treatment that is simply empirical."

There is a tradition to organize IUTAM Symposia "Creep in Structures" every ten years: the first Symposium was organized by N.J. Hoff in Stan ford (1960), the second one by J. Hult in Goteborg (1970), and the third one by A.R.S. Ponter in Leicester (1980). The fourth Symposium in Cracow, September 1990, gathered 123 par ticipants from 21 countries and reflected rapid development of the theory, experimental research and structural applications of creep and viscoplas ticity, including damage and rupture. Indeed, the scope of the Sympo sium was broad, maybe even too broad, but it was kept according to the tradition. Probably the chairman of "Creep in Structures V" in the year 2000 (if organized at all) will be forced to confine the scope substantially. Participation in the Symposium was reserved for invited participants, suggested by members of the Scientific Committee. Total number of sug gestions was very large and the response - unexpectedly high. Apart from several papers rejected, as being out of scope, over 100 papers were accepted for presentation. A somewhat unconventional way of presenta tion was introduced to provide ample time for fruitful and well prepared discussions: besides general lectures (30 minutes each), all the remain ing papers were presented as short introductory lectures (10 minutes) followed by a I-hour poster discussion with the authors and then by a general discussion. Such an approach made it possible to present general ideas orally, and then to discuss all the papers through and through."

In recent years microstructural analysis has been a rapidly changing field of scien tific endeavor. No longer are the efforts of the microstructural analysts (sometimes referred to as metallographers, materialographers, ceramographers, and similar desig nations) limited to the tasks of polishing, etching, and photographing specimens of materials. The performance demanded of materials used for many current applica tions requires much more complete characterizations than were possible only a scant few years ago. Although the individuals who have been expected to develop new and improved techniques to permit these required characterizations have been severely challenged, in large part they have met the challenge. In view of the many new developments in the field of microstructural analysis and recognizing the requirements to communicate these developments to the wide audience that might make use of them, the American Society for Metals and the In ternational Metallographic Society joined forces to co-sponsor a symposium that was intended to bring participants and attendees up to date on the subject "Inter pretive Techniques for Microstructural Analysis." This symposium was held in Min neapolis, Minnesota, USA, June 29 and 30, 1975. It followed two earlier symposia co-sponsored by the same two societies on other subjects of current interest to the metallographic community, Microstructural Analysis - Tools and Techniques, 1972, and Metallographic Specimen Preparation - Optical and Electron Micros copy, 1973."

This volume contains the papers presented at the NATO Advanced Research Workshop in "Reflection High Energy Electron Diffraction and Reflection Electron Imaging of Surfaces" held at the Koningshof conference center, Veldhoven, the Netherlands, June 15-19, 1987. The main topics of the workshop, Reflection High Energy Electron Diffraction (RHEED) and Reflection Electron Microscopy (REM), have a common basis in the diffraction processes which high energy electrons undergo when they interact with solid surfaces at grazing angles. However, while REM is a new technique developed on the basis of recent advances in transmission electron microscopy, RHEED is an old method in surface crystallography going back to the discovery of electron diffraction in 1927 by Davisson and Germer. Until the development of ultra high vacuum techniques in the 1960's made instruments using slow electrons more accessable, RHEED was the dominating electron diffraction technique. Since then and until recently the method of Low Energy Electron Diffraction (LEED) largely surpassed RHEED in popularity in surface studies. The two methods are closely related of course, each with its own specific advantages. The grazing angle geometry of RHEED has now become a very useful feature because this makes it ideally suited for combination with the thin growth technique of Molecular Beam Epitaxy (MBE). This combination allows in-situ studies of freshly grown and even growing surfaces, opening up new areas of research of both fundamental and technological importance.

High pressure science is a rapidly growing diverse fi. e1d. The high pressure technique has become a powerful tool for both the study and preparation of materials. In spi. te of the many high pressure conferences held in recent years, I felt that there was a need for scientists within a well-defined area (not bound merely by the common experimental technique) to meet in an atmosphere conducive to frank exchange and close interaction. In this spirit, the Cleveland State University hosted such a conference from July 20 to 22, 1977, in which the physics of solids under high pressures and at low tempera tures was specifically examined. Both the original and review papers presented at the conference and the candid discussions following their presentations appear in this volume. They clearly cover a rather complete spectrum of current research in the physics of solids at high pressures and low temperatures. I wish to thank the National Aeronautics and Space Administra tion, the Office of Naval Research and the National Science Founda tion for their financial support of the conference. In addition, I wish especially to thank Steinar Huang for his unceasing assistance in arranging this conference. I also wish to thank him and Francis Stephenson for their assistance in preparing this book. C. W. Chu, Chairman, International Conference on High Pressure and Low Temperature Physics v Contents HYDROGEN AND METAL-HYDRIDES (Chairman: I. Spain) PROSPECTS FOR METALLIC HYDROGEN 1 A. L."

This volume chronicles the proceedings of the Symposium on Particles on Surfaces: Detection, Adhesion and Removal held under the auspices of the Fine Particle Society in San Francisco, July 28-August 2, 1986. The study of particles on surfaces is extremely important in many areas of human endeavor (ranging from microelectronics to optics to biomedical). A complete catalog of modern precision and sophisticated technologies where particles on surfaces are of cardinal importance will be prohibitively long, but the following eclectic examples should underscore the concern about particles on a variety of surfaces. In the semiconductor world of shrinking dimensions, particles which, a few years ago, were cosmetically undesirable but functionally innocuous can potentially be killer defects now. As the device sizes get smaller, there will be more and more concern about smaller and smaller particles. In the information storage technology, the gap between the head and the disk is very narrow, and if a particle is trapped in the gap that can have very grave consequences. The implications of particulate contamination on sensitive optical surfaces is all too manifest. So the particulate contamination on surfaces is undesirable from functional, yield and reliability points of view. This symposium was organized with the following objectives in mind: to bring together active practitioners in this field; to provide a forum for discussion of the latest research and development activities in this area; to provide opportunity for cross-pollination of ideas; and to highlight topics which needed intensified effort.

The need for alternate energy sources has led to the develop ment of prototype fusion and MHD reactors. Both possible energy systems in current designs usually require the use of magnetic fields for plasma confinement and concentration. For the creation and maintenance of large 5 to 15 tesla magnetic fields, supercon ducting magnets appear more economical. But the high magnetic fields create large forces, and the complexities of the conceptual reactors create severe space restrictions. The combination of re quirements, plus the desire to keep construction costs at a mini mum, has created a need for stronger structural alloys for service at liquid helium temperature (4 K). The complexity of the required structures requires that these alloys be weldable. Furthermore, since the plasma is influenced by magnetic fields and since magnet ic forces from the use of ferromagnetic materials in many configur ations may be additive, the best structural alloy for most applica tions should be nonmagnetic. These requirements have led to consideration of higher strength austenitic steels. Strength increases at low temperatures are achieved by the addition of nitrogen. The stability of the austenitic structure is retained by adding manganese instead of nickel, which is more expensive. Research to develop these higher strength austenitic steels is in process, primarily in Japan and the United States."

The interest in materials property determination by nondestructive means is increasing especially for in-process and in-service inspection of structural and electronic materials and components. Such attention is due to several factors, including increased automation of manufacturing processes, the demand for greater reliability in consumer products and military hardware, and more severe demands on the performance of materials. This book represents the proceedings for the Symposium on Nondestructive Hethods for Haterial Property Determination held April 6 to 8, 1983, at the Hotel Hershey in Hershey, Pennsylvania. That symposium was one of the first meetings concerned specifically with nondestructive material property determination (characteriza tion). Its purpose was to stimulate intercourse between researchers, engineers, and theoreticians so as to focus upon the multidiseiplinary problems of advancing the state of the art in this area. The papers in the book are concerned mainly with acoustic (including ultrasonic), magnetic, electrical, and x-ray diffraction techniques and applications. Hany of the papers describe well developed technologies that are currently in practical application, while others discuss concepts which will never emerge from the laboratory but perhaps will provide the groundwork for more practical ideas."

During late 1978, a symposium entitled "Science Underlying Radioactive Waste Management" was one component of the Annual Meet ing of the Materials Research Society held in Boston, Massachusetts. The purpose of this Symposium was to bring together for the first time the entire range of sciences that form the basis for the treatment, solidification and isolation of radioactive wastes. Some 79 papers were presented to an international audience of over 300. The Symposium was such an impressive success that another will be held at the 1979 Annual Meeting of the Materials Research Society. The proceedings of the forthcoming symposium will also be published and it is for this reason that the present volume has been desig nated Volume 1. The scope of the Symposium was defined by the following steer ing committee: Rustum Roy, The Pennsylvania State University (Chairman) Richard S. Claassen, Sandia Laboratories Don Ferguson, Oak Ridge National Laboratory Victor I. Spitsyn, U.S.S.R. Academy of Sciences, Moscow David B. Stewart, United States Geological Survey Torbjorn Westermark, Royal Institute of Technology, Stockholm. The program was organized by the following committee: Gregory J. McCarthy, The Pennsylvania State University (Cha- man) Harry C. Burkholder, Battelle Memorial Institute Arnold M. Friedman Argonne National Laboratory Werner Lutze, Hahn-Meitner Institut, Berlin John G. Moore, Oak Ridge National Laboratory Robert W. Potter, II, United States Geological Survey Richard L. Schwoebe1, Sandia Laboratories Roger W. Staehle, Ohio State University."

Dr. George P. Thomon, Nobel Laureate in Physics said, "We have labelled civilizations by the main materials which they have used: The Stone Age, the Bronze Age and the Iron Age *** a civilization is both developed and limited by the materials at its disposal. Today, man lives on the boundary between the Iron Age and a New Materials Age." The ever more stringent requirements for materials to accomplish specific functions and withstand extreme conditions, as dictated by the needs of industry and defense, con tinue to spur ever more intensive research in Materials Science. According to the recent report "Trends and Opportunities in Materials Research" a vital goal of materials research is to design synthesize and fabricate in high yield, new materials with properties that can be pre dicted, varied and controlled. In the past this has been a fairly empirical process, but as we gain more comprehensive understanding of the behavior of matter on an atomic and molecular scale this goal becomes ever more attain able. An important recent trend is the increasing sophistication and power of theoretical approaches. Aided by the development of computers and versa tile numerical techniques, as well as concepts from statistical mechanics, theorists are beginning to confront the complexity of real materials. Important advances are expected through a concentrated attack on model systems in which the theorist, experimental scientist and engineer all work together towards designing new materials and controlling their properties.

In order to make the subject manageable the term 'injection moulding' has been restricted in its use so that only those processes which rely on thermal softening of the polymeric materials have been described and discussed in this book. It is intended to discuss the subject of reaction injection moulding in a separate book. However, even with this omission, the subject is still a very large one as nowadays many sorts or types of polymers are injection moulded. For example, it is estimated that one-third of all plastics materials are injection moulded-the range of products produced is enormous and increases daily. Because most moulding materials are based on plastics, in particular thermoplastics, the materials guides which form a large part of this book concentrate on the moulding of thermoplastics materials. Such guides should only be treated as general guidelines as each of the materials is normally available in a wide range of grades. These may differ in polymer molecular weight, molecular weight distribution, the additives used and their concentration, the physical form of the moulding compound, etc. A wide range of processing behaviours and end-use properties is therefore possible from any of the materials listed. This versatility is typified by the rubbery polymers which are compounded into an incredibly wide range of compounds. Because of this versatility only a very general guideline has been given for such materials.

The continuous and ever expanding development of high-temperature tech nology involves the use of high -temperature refractory materials and one of the most important classes of these is the oxides, i.e., compounds of elements with oxygen. Oxides are the oldest refractory compounds known in technology and this is connected with their high chemical stability and abundance in nature. In addition to the use of oxides as raw materials for metallurgical processes, the refractoriness, chemical stability, and magnetic and other technically important properties of oxides have been put to use since antiquity. At the present time the importance of oxides as bases of many materials for new technology is substantial and is growing rapidly with the development of processes for the direct conversion of various forms of energy into electrical energy, the development of nuclear technOlogy, electronics, semiconductor and dielectric technOlogy, and cosmic technology, where the refractoriness and chemical stability of oxides are used in combination with their specific physical properties. Oxides are the foundation of the so-called oxygen -containing or oxygen refractory materials, which are fundamental to high-temperature tech nology. Oxides are no less important as the bases of practically all structural ma terials and rocks. A number of oxides are involved in biological processes."

LIOn Delamination of Laminated Composites (a) Fiber-Reinforced Composites Considerable technological advances in the production of high-strength fibers (graphite, boron, etc.) have led to a wide use of light high-strength composite materials (graphite epoxy, boron-epoxy, etc.). It is expedient, to make thin walled composite rods, plates, and shells from such materials. Plates can be made by bonding a set of unidirectional thin fiber layers, Fig.l.l. Such plates are orthotropic, as a rule. A random short-fiber composite is shown in Fig. 1.2. Fiber-reinforced composites are widely used in thin-walled aircraft structures because of their specific high strength. For example, the graphite-epoxy composite is characterized by a unidirectional tensile strength of 1.4 GPa while the density is 1.6 Mg/rrt? . For comparison, we may take a steel (steel 4340) whose corresponding properties are identified by values like 1.2 GPa and 7.8 Mg/rrt? . 1. INTRODUCTION Figure 1.1 2 1.1. On Delamination of Laminated Composites Figure 1.2 3 1. INTRODUCTION It is characteristic for laminated plastic material to possess a fairly low bonding. Therefore, low-velocity impacts and defects in manufacturing lead to local delamination. (b) Linear Problems of Delamination Buckling Delamination can significantly reduce the compressive strength and stiffness of the laminate. Local delamination can be considered as a crack in the bond. Under buckling there appears a high interlaminate stress at the crack edge that leads to a spreading of the crack. Delamination growth can lead to structural instability."

Industrial radiography is a well-established non-destructive testing (NDT) method in which the basic principles were established many years ago. However, during 1993-95 the European Standards Organisa tion (CEN) commenced drafting many new standards on NDT including radiographic methods, and when completed these will replace national standards in all the EC member countries. In some cases these standards vary significantly from those in use in the UK at present. These CEN standards are accepted by majority, not unanimous voting, so they will become mandatory even in countries which vote against them. As most are likely to be legal by the time this second edition is published, they are described in the appropriate places in the text. The most important new technical development is the greater use of computers in radiology. In the first edition, computerized tomography was only briefly mentioned at the end of Chapter 11, as it was then largely a medical method with only a few equipments having found a place in industrial use. The method depends on a complex computer program and a large data store. Industrial equipments are now being built, although their spread into industry has been slow. Computer data storage is also being used for radiographic data. Small computers can now store all the data produced by scanning a radiographic film with a small light-spot, and various programs can be applied to these data."

Carbon fibre reinforced carbon composites form a very specialized group of materials. They may be considered as a development of the family of carbon fibre reinforced polymer composites which are becoming ever more prevalent in modern engineering. Since the early 1960s a large number of so-called 'advanced materials' have appeared on the scene. Carbon arbon is arguably the most successful of all these products finding many and varied applications. In the field of Formula 1 motor racing for example, the present levels of performance simply could not be achieved without the use of carbon-carbon brakes and clutches. Despite the materials' obvious assets, they have not, and will not, reach their full potential until their inherent problems of excessive production costs and oxidation resistance have been addressed properly. In this respect the 'carbon-carbon story', of much potential but only limited success, serves as a lesson to all those involved in materials research, development and application. In writing this book I have tried to set up a logical progression of what the materials are, how they are made, what their assets and deficiencies are, what they are used for and to what extent they are commercially exploited. Each specialized chapter may be considered in isolation or as part of a sequence, whereas the final chapter provides a summary of the principal concepts as well as a basic review of the economic situation past, present and, hopefully, future.

This volume contains the edited Proceedings of the Sixth World Round Table Conference on Sintering, held in Herceg-Novi, Yugoslavia on September 2-6, 1985. It was organized by the International Institute for the Science of Sintering (IISS), headquartered in Beograd. Every fourth year since 1969, the Institute has organized such a Round Table Conference on Sintering, each has taken place at some selected lo cation within Yugoslavia. A separate series of IISS Summer Schools have also been held at four year intervals, but they have been offset by about two years, so they occur between the main Conferences. As a rule, the Summer Schools have been devoted to more specific topics and they also take place in different countries. The aim of these Conferences and their related Summer Schools has been to bring together scientists from allover the world who work in various fields of science and technology concerned with sinter ing and sintered materials. A total of six IISS Conferences have been held over the period 1969-1985, and they have been supplemented by the three Summer Schools held in Yugoslavia, Poland and India (in 1975, 1979 and 1983, respectively). This most recent five day Conference addressed the fundamental scien tific background as well as the technological state-of-the-art in sintering and sintered materials. It encompassed many of the high technology sintered materials needed for a wide variety of research and industrial applications."