Ordered Intermetallics


Book Description

Ordered intermetallics constitute a unique class of metallic materials which may be developed as new-generation materials for structural use at high temperatures in hostile environments. At present, there is a worldwide interest in intermetallics, and extensive efforts have been devoted to intermetallic research and development in the U.S., Japan, European countries, and other nations. As a result, significant advances have been made in all areas of intermetallic research. This NATO Advanced Workshop on ordered intermetallics (1) reviews the recent progress, and (2) assesses the future direction of intermetallic research in the areas of electronic structure and phase stability, deformation and fracture, and high-temperature properties. The book is divided into six parts: (1) Electronic Structure and Phase Stability; (2) Deformation and Dislocation Structures; (3) Ductility and Fracture; (4) Kinetic Processes and Creep Behavior; (5) Research Programs and Highlights; and (6) Assessment of Current Research and Recommendation for Future Work. The first four parts review the recent advances in the three focus areas. The fifth part provides highlights of the intermetallic research under major programs and in different institutes and countries. The last part provides a forum for the discussion of research areas for future studies.




Intermetallics


Book Description

Intermetallic compounds play an extraordinary role in daily life for construction materials and well-defined functions that are based on their specific chemical and physical properties, e.g. magnetism and superconductivity. High-tech materials are meanwhile indispensable in our technology-driven information society. The Periodic Table comprises more than 80 metallic elements which offer an incredible potential for formation of binary, ternary and even multinary intermetallic compounds with peculiar crystal structures and properties. The present textbook introduces into the basics of intermetallic chemistry with an emphasis on crystal chemistry and selected chemical and physical properties.




Physical Metallurgy and processing of Intermetallic Compounds


Book Description

The attractive physical and mechanical properties of ordered intermetallic alloys have been recognized since early in this century. However, periodic attempts to develop intermetallics for structural applications were unsuc cessful, due in major part to the twin handicaps of inadequate low-temper ature ductility or toughness, together with poor elevated-temperature creep strength. The discovery, in 1979, by Aoki and Izumi in Japan that small additions of boron caused a dramatic improvement in the ductility of Ni3Al was a major factor in launching a new wave of fundamental and applied research on intermetallics. Another important factor was the issuance in 1984 of a National Materials Advisory Board reported entitled "Structural Uses for Ductile Ordered Alloys," which identified numerous potential defense-related applications and proposed the launching of a coordinated development program to gather engineering property and processing data. A substantial research effort on titanium aluminides was already underway at the Air Force Materials Laboratory at Wright Patterson Air Force Base in Ohio and, with Air Force support, at several industrial and university laboratories. Smaller programs also were under way at Oak Ridge National Laboratory, under Department of Energy sponsorship. These research efforts were soon augmented in the United States by funding from Department of Defense agencies such as Office of Naval Research and Air Force Office of Scientific Research, and by the National Science Foundation.




High Temperature Aluminides and Intermetallics


Book Description

This volume of proceedings is concerned with an increasingly important area, that of intermetallics and high temperature aluminides, which has recently been attracting a great deal of attention. Nearly 150 papers presented at the meeting held in San Diego in September 1991 are reproduced here. They cover a wide range of related topics such as the bonding characteristic and alloying behaviour of TiA1 intermetallic compounds and the cleavage fracture of ordered intermetallic alloys. All the papers have been reviewed according to the standards set by Materials Science and Engineering. This book will be of interest to metallurgists and materials scientists working with composites who are interested in the latest developments in this fast–moving field.




Intermetallics


Book Description

Derived from the highly acclaimed series Materials Science and Technology, this book covers the properties as well as the present and emerging applications of intermetallics. Mechanical characteristics, microstructure as well as the environmental influence on intermetallics are treated in depth. In addition, the prospects and risks inherent in materials development as well as typical applications of intermetallics are critically assessed. It is the author's aim to provide the basis for understanding the physical mechanisms, which influence the properties of the materials and ultimately their areas of application. Materials covered include: Titanium Aluminides and Related Phases * Nickel Aluminides and Related Phases * Iron Aluminides and Related Phases * Cu-Base Phases * A15 Phases * Laves Phases * Rare-Earth Compound * Beryllides * Silicides Intermetallics is a valuable source of information for researchers and graduate students working in materials science, metallurgy, condensed-matter physics, and engineering.




Intermetallics


Book Description

The fascinating world of intermetallics is largely unexplored. There are many exciting physical properties and important technological applications of intermetallics, from magnetism to superconductivity. The main focus of this book is on the statistics, topology and geometry of crystal structures and structure types of intermetallic phases. The underlying physics, in particular chemical bonding, is discussed whenever it helps understand the stability of structures and the origin of their physical properties. The authors' approach, based on the statistical analysis of more than twenty thousand intermetallic compounds in the data base Pearson's Crystal Data, uncovers important structural relationships and illustrates the relative simplicity of most of the general structural building principles. It also shows that a large variety of actual structures can be related to a rather small number of aristotypes. The text aims to be readable and beneficial in one way or another to everyone interested in intermetallic phases, from graduate students to experts in solid state chemistry and physics, and materials science. For that purpose it avoids the use of enigmatic abstract terminology for the classification of structures. Instead, it focuses on the statistical analysis of crystal structures and structure types in order to draw together a larger overview of intermetallics, and indicate the gaps in it - areas still to be explored, and potential sources of worthwhile research. The text should be read as a reference guide to the incredibly rich world of intermetallic phases.




Intermetallic Chemistry


Book Description

Intermetallic science is closely related to physics, chemistry, metallurgy, materials science & technology, and engineering. This book emphasizes the chemical aspects of this science, and therefore the mutual reactivity of metals and the characteristics of intermetallic compounds. Topics included are:• Phase diagrams of alloy systems. Many intermetallic systems form several compounds, generally not obeying common simple stoichiometric rules, which are often homogeneous in a certain range of compositions. The stability and extension of these phases are conveniently presented through phase diagrams.• Selected aspects of intermetallics structural chemistry, with emphasis on the solid state. The general structural characteristics of intermetallic phases are considered, with attention to nomenclature and to alternative and complementary methods of presenting crystal-chemical data. A brief account is given of derivative and degenerate structures, modular aspects of crystal structures, and of a few special groups of alloys such as quasicrystals and amorphous alloys. A number of selected structural prototypes with typical features, their possible grouping in structural "families and their distribution among different types of alloys are provided.• Intermetallic reactivity trends in the Periodic Table. Attention is given to a few selected elemental parameters such as electron configuration and valence electron number and to their changes along the Table, which act as reference factors of the intermetallic behaviour. As an example, the relationships are considered between crystal structure and the number of valence electrons per atom (or per formula) in various classes of compounds or solid solution phases.• Alloying behaviour systematics of intermetallic systems with a description of the intermetallic reactivity of each element, or group of elements, in the order of their position in the Periodic Table. For each pair of metallic elements, their capability to form intermediate phases is summarised by maps and schemes. • A description of small scale preparation methods of intermetallics. A number of interesting and significant peculiarities are, e.g., those related to their high melting points, insolubility in common solvents, etc.· Systematic treatment of alloying behaviour· Wide overview of intermetallic chemistry· Illustrated, with many examples







Mechanical Behaviour of Materials - VI


Book Description

Significant progress in the science and technology of the mechanical behaviour of materials has been made in recent years. The greatest strides forward have occurred in the field of advanced materials with high performance, such as ceramics, composite materials, and intermetallic compounds. The Sixth International Conference on Mechanical Behaviour of Materials (ICM-6), taking place in Kyoto, Japan, 29 July - 2 August 1991 addressed these issues. In commemorating the fortieth anniversary of the Japan Society of Materials Science, organised by the Foundation for Advancement of International Science and supported by the Science Council of Japan, the information provided in these proceedings reflects the international nature of the meeting. It provides a valuable account of recent developments and problems in the field of mechanical behaviour of materials.




Mechanical Alloying And Milling


Book Description

This book surveys the broad field of mechanical alloying from a scientific and technological perspective to form a timely and comprehensive resource valuable to both students and researchers. The treatment progresses from the historical background through a description of the process, the different metastable effects produced, and the mechanisms of