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Thermodynamics and Phase Diagrams



Ursula R. Kattner


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.
Encyclopedia of Materials


Phase Diagrams, Processing, Thermodynamics


Kattner, U. (2017), Thermodynamics and Phase Diagrams, Encyclopedia of Materials (Accessed June 16, 2024)


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Created February 19, 2017