Structural And Phase Stability Of Alloys

This vohune contains the papers presented at the Adriatico Research Conference on Structural and Phase Stability of Alloys held in Trieste, Italy, in May 1991, under the auspices of the International Centre for Theoretical Physics. The conference brought together participants with a variety of interests in theoretical and experimental aspects of alloys from Argentina, Belgium, Bulgaria, Czechslovakia, France, Germany, Italy, Japan, Mexico, People's Republic of Congo,Portugal, Switzerland, United Kingdom, United States, U. S. S. R. , and Venezuela. The conference was purposely designed to succinctly cover experimental and the oretical aspects of magnetic and non-magnetic alloys, surfaces, thin films and nanos tructures. The Conference opened with an overview of a select class of advanced structural materials, with a potential in engineering applications, for which the con ventional "physics" approach, both theoretical and experimental, should have a sig nificant impact. A number of papers were dedicated to the use of phenomenological approaches for the description of thermodynamic bulk and surface properties. It was clear from these presentations that the phenomenological models and simulations in alloy theory have reached a high degree of sophistication. Although with somewhat limited predictive powers, the phenomenological models provide a valuable tool for the understanding of a variety of subtle phenomena such as short-range order, phase stability, kinetics and the thermodynamics of surfaces and antiphase boundaries, to name a few.

Hardbound. The main purpose of this book is to describe the modern tools of solid state physics (in particular, electronic structure calculations and statistical thermodynamics) that enable us to understand ordering effects in alloys and to determine phase diagrams. This approach is used more to throw light on the most important physical mechanisms rather than to be able to make accurate predictions suitable for particular applications. On the other hand, more phenomenological, practically oriented approaches can expand the scope of these new theoretical insights. A second purpose of the book is to show that materials science can provide wonderful and too often ignored examples to test and discuss the most fundamental physical theories. For example, many real alloys on a face centered cubic lattice are marvellous examples of the Ising model on this lattice with many different ordered structures, commensurate or not.The text is therefore defi

One of the ultimate goals of materials research is to develop a fun damental and predictive understanding of the physical and metallurgical properties of metals and alloys. Such an understanding can then be used in the design of materials having novel properties or combinations of proper ties designed to meet specific engineering applications. The development of new and useful alloy systems and the elucidation of their properties are the domain of metallurgy. Traditionally, the search for new alloy systems has been conducted largely on a trial and error basis, guided by the skill and intuition of the metallurgist, large volumes of experimental data, the principles of 19th century thermodynamics and ad hoc semi-phenomenological models. Recently, the situation has begun to change. For the first time, it is possible to understand the underlying mechanisms that control the formation of alloys and determine their properties. Today theory can begin to offer guidance in predicting the properties of alloys and in developing new alloy systems. Historically, attempts directed toward understanding phase stability and phase transitions have proceeded along distinct and seemingly diverse lines. Roughly, we can divide these approaches into the following broad categories. 1. Experimental determination of phase diagrams and related properties, 2. Thermodynamic/statistical mechanical approaches based on semi phenomenological models, and 3. Ab initio quantum mechanical methods. Metallurgists have traditionally concentrated their efforts in cate gories 1 and 2, while theoretical physicists have been preoccupied with 2 and 3.

Understanding the electronic structure of solids is a basic part of theoretical investigation in physics. Application of investigative techniques requires the solid under investigation to be "periodic." However, this is not always the case. This volume addresses three classes of "non-periodic" solids currently undergoing the most study: alloys, sur

This book is dedicated to the fundamental physical aspects of stability, the influence of structural defects on the properties and structural phase transformations of BCC alloys. The authors present patterns that occur in the structural-phase states of functional alloys with low stability or instability under thermal cycling effects. Structural-phase transformations and the physical laws governing the influence of the thermomechanical effect on the properties of alloys are examined to advance development of technological processes for processing functional materials. Features: Studies the correlation between structural phase states and changes in the physico-mechanical properties of intermetallic compounds Explores the influence of thermomechanical cycling on the properties of functional alloys Details low-stability pretransition states in alloys