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Thermodynamics and Phase Diagrams

Published

Author(s)

Ursula R. Kattner

Abstract

Thermodynamics is a field of physics and chemistry. It uses mathematics to describe changes in energy and entropy (disorder) of a material that is subject to mechanical, thermal or chemical action. It is most frequently used to describe the conditions that lead to minimization of energy and thereby predict the equililbrium-state of the material. Sometimes, the difference between the free energies of the current state and the equilibrium state is used to give the temporal rate at which a system approaches equilibrium. In its simplest form, thermodynamics neglect non-hydrostatic stress, surface energy and many other things. Then it is possibole to simply describe the energy of a system to be minimized is the free energy. The enthalpy (or heat content) and the density of a material may also be described with thermodynamics. In many physical processes, it is useful to consider a system to be at equilibrium in small regions, while radients on a larger length scale may still exist.
Citation
Encyclopedia of Materials

Keywords

Phase Diagrams, Processing, Thermodynamics

Citation

Kattner, U. (2017), Thermodynamics and Phase Diagrams, Encyclopedia of Materials (Accessed October 7, 2024)

Issues

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Created February 19, 2017