The Application of Thermodynamics to the Development of Processes and Materials

TitleThe Application of Thermodynamics to the Development of Processes and Materials
Publication TypeJournal Article
Year of Publication1994
AuthorsSpencer, PJ, Eriksson, G, Richthofen, A von
JournalCODATA '94, 14th International Conference
Keywordsceramics, chemsage, dioxins, Fly Ash, incineration, light alloys, metastable phases, pvd, refractory, thermodynamic data, Waste
Abstract

The key role of thermodynamic calculations in defining optimum conditions for carrying out and understanding materials processes has long been recognized. Nevertheless, it is only through the significant developments in computer software for complex equilibrium calculations, in the modelling of solution phases with complex structures, in the accumulation and critical evaluation of experimental thermodynamic data both for pure substances and for complex mixtures, that the full potential of thermodynamic calculation methods can now be more fully realized.

There are important practical reasons for making full use of the thermodynamic calculation 'packages' now available from a number of sources. Apart from the capability of simulating processes of interest, whereby a process can be improved by determination and optimization of the critical parameters, the speed of calculation now available offers a real possibility to use the calculations for process control in certain cases - for example, to control the composition of the gas atmosphere in carburizing or nitriding processes. Information gained from thermodynamic calculations for complex systems is also providing new insight into the basis of compositional and phase changes under different conditions. This information could not be gained with the simplified modelling and estimated data available earlier.

Still more attractive are the very significant time and cost benefits associated with the use of thermodynamic calculations in materials and process development, for such theoretical studies allow a very great reduction in the amount of experimental development work needed. By proceeding hand-in-hand, calculation and experiment make much more rapid and reliable progress than that associated with trial-and-error methods.

In this paper, examples are presented of how thermodynamic data from the databases of the Scientific Group Thermodata Europe (SGTE) are being combined with different software to provide a sound basis for the development of materials and processes of different types.

Examples discussed:

 

  • A thermodynamic database for the development of new light alloys - COST 507
  • The development of complex, metastable refractory coatings using physical vapour deposition (PVD) techniques
  • The theoretical investigation of toxic emissions associated with waste treatment processes
    • Incineration of fly-ash
    • Incineration of organic waste