This book is dedicated to Professor E. Bonnier and Dr Himo Ansara.

Professor Bonnier, the first chairman of SGTE, provided tremendous enthusiasm, vision and patience during the creation, development and implementation of a European-based structure for the Scientific Group Thermodata Europe (SGTE). His wise leadership through the initial years of SGTE as a European group, first as a project supported by the French CNRS and afterwards by DG XIII of the European Community, was largely responsible for the establishment of the present wide-reaching joint activities of SGTE members.

Himo Ansara was the first manager of the SGTE Pure Substance Database. He had an infectious love for the application of Gibbs energy thermodynamics to practical problems which led to the generation of valuable databases as well as to the development of fundamental Gibbs energy models for non-ideal solutions. His many insights have made thermodynamics such a valuable tool to the materials industry for the development and optimization of materials and processes.

Their colleagues in SGTE, present and past, will always remember their contributions with affection.

The major purpose of this book is to illustrate how thermodynamic calculations can be used as a basic tool in the development and optimisation of materials and processes of many different types.

Since the first edition of this book was published in 1996, the field of 'computational thermochemistry' has exploded as the reliability and scope of commercial databases have grown, as software packages have been developed to cover kinetic considerations and as more scientists have become acquainted with the potential that the field offers for understanding and modeling industrial and environmental processes. The examples selected in this book are, to a large extent, real case studies dealt with by members of SGTE and their collaborators in the course of their work.

SGTE is a consortium of European and North-American research organisations working together to develop high-quality thermodynamic databases for a wide variety of inorganic and metallurgical systems. SGTE has been at the forefront of the broader international effort to unify thermodynamic data and assessment methods by promoting use of standard reference data for the elements and binary systems, and generic models to represent the variation in thermodynamic properties with temperature and composition. SGTE data can be obtained via members and their agents for use on personal computers with commercially available software, to enable users to undertake calculations of complex chemi­cal and phase equilibria efficiently and reliably. The case studies presented in the book have been treated using SGTE data in combination with such software.

Members of SGTE have played a principal role in promoting the concept of 'computational thermochemistry' as a time- and cost-saving basis for the control and modelling of various types of materials processes. In addition, such calculations provide crucial process-related information regarding the nature, amounts and distribution of environmentally hazardous substances produced during the different processing stages.
While further developments in data evaluation techniques, in the modelling of Gibbs energies of the different types of stable and metastable phases, in the coupling of thermodynamics and kinetics and in the scope of application software are still needed, the case studies presented in this volume demonstrate convincingly that thermochemical calculations have great potential for providing a sound and inexpensive basis for materials and process development in many areas of technology.

Alan Dinsdale
Chairman

On the market since February 2008.

This substantially revised new edition explores both the theoretical background to thermodynamic modelling and its wide range of practical applications. These applications include the analysis of hot salt and other types of high-temperature corrosion, understanding the loss of corrosion resistance in stainless and other types of steel, the processing of steels, as well as the use of thermodynamics to improve the functionality of materials for microelectronics and lighting applications, and in the analysis of nuclear safety issues. New case studies also illustrate applications to kinetically-controlled processes such as the solidification, melting and heat treatment of alloys as well as the production of silicon and titanium oxide pigment.

The SGTE casebook will be a valuable reference for those manufacturing steels and other materials, those using materials in high-temperature applications such as the power industry and also those engaged in other areas such as microelectronics and lighting.

Below is given the table of contents of the casebook:

Chapter 1: Theoretical Background

'The real raison d'être for the continuation of extensive experimental research in metallurgical thermochemistry is the potential application of its principles and data to practical, in particular industrial, problems. For this purpose the gathering of raw experimental data is obviously not enough. Missing numerical information must be supplemented by estimates ... Raw data must be sifted and critically evaluated to provide for every chemical system a consistent set of thermochemical properties....

In practice, it is true, the knowledge of reaction rates is as important as that of equilibrium, if not more so, but the kinetic problems can only be tackled when the thermodynamic ones have been settled. It is also true that, in practice, metallurgical reactions are quite involved ... but with some effort it will be found that even complicated chemical processes may be broken up into simpler reactions which are accessible to normal thermodynamic evaluation.'

The above points are made in the 5th edition of MetallurgicalThermochemistryby Kubaschewski and Alcock in 1979 [79Kub]. Elsewhere in the same book the term databank is used, albeit in quotation marks. Most of the statements are still relevant: computer supported calculations provide an enormous potential for the application of thermodynamic principles to the solution of practical problems. There is still the need for good estimates arising from the lack of data in certain fields of interest, and critical evaluation of raw experimental results to obtain consistent thermodynamic data sets for complete chemical systems is still of paramount importance. Nevertheless, the development of software for treating thermochemical problems has made considerable advances in the past two decades and the questions that remain open can be tackled in a much more comprehensive way.

The enormous effort involved in data collection and evaluation as carried out for example by Kubaschewski for pure substance data and by Kaufman [78Kau] in the field of alloy phases is now a somewhat less arduous task due to the availability to thermochemists of the computer. This has made it possible to treat thermochemistry in a completely new way. The computer, because of its data storage and management and its 'number-crunching' capabilities, has enabled us to look at the thermochemistry of a system as a whole, i.e. in many cases the user needs nothing more than a list of elements in his system and the values of the global variables temperature, pressure and element concentrations to carry out a theoretical study. Calculations can then be made of the phases stable at equilibrium, their amounts and compositions, and even information about the degree of instability of the phases not present at equilibrium can be provided. The flow sheet shown in Figure I.1 may be used to illustrate the work procedure entailed in the application of computational thermochemistry.

The purpose of the present volume is to present some examples of such calculations and thus to demonstrate the enormous potential of this new technique. The computerised databases are still limited but a considerable effort is ongoing to expand them. SGTE is making a major effort to provide comprehensive high-quality self-consistent computerised thermodynamic databases both for pure substances and for mixtures of all types and is playing a leading role in establishing methods for data evaluation and modelling of solution phases. Software for the storage and retrieval of assessed data has been developed and there are a number of application programs to treat different aspects of chemical equilibrium [70Kau, 80Bar, 83Tur, 84Sch, 85Sun, 85Tho, 85Tur, 87Bar, 88Che, 880m, 88Roi, 88Sun, 88Tho, 002CAL].


References