Tammann temperature and Hüttig temperature

The Tammann temperature (also spelled Tamman temperature) and the Hüttig temperature of a given solid material are approximations to the absolute temperatures at which atoms in a bulk crystal lattice (Tammann) or on the surface (Hüttig) of the solid material become sufficiently mobile to diffuse readily, and are consequently more chemically reactive and susceptible to recrystallization, agglomeration, or sintering. The Tammann temperature is usually taken to be 0.5 times the absolute temperature of the compound's melting point.

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