Melting

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Mechanical failure modes
Buckling
Corrosion
Creep
Fatigue
Fracture
Melting
Thermal shock
Wear

In physics, melting is the process of heating a solid substance to a point (called the melting point) where it turns liquid. An object that has melted is molten.

[edit] Explanatory

Not only is heat required to raise the temperature of the solid to the melting point, but the melting itself requires heat; see also latent heat and heat of fusion.

From a thermodynamics point of view, at the melting point the change in Gibbs free energy (<math>\Delta G</math>) of the Material is zero, because the enthalpy (<math>H</math>) and the entropy (<math>S</math>) of the material are increasing (<math>\Delta H, \Delta S > 0</math>). Melting phenomenon happens when the Gibbs free energy of the liquid becomes lower than the solid for that material. At various pressures this happens at a specific temperature. It can also be shown that:

<math>\Delta S = \frac {\Delta H} {T}</math>

The "<math>T</math>","<math>\Delta S</math>", and "<math>\Delta H</math>" in the above are respectively the temperature at the melting point, change of entropy of melting, and the change of enthalpy of melting.

Freezing, the process of turning a liquid to a solid, is the opposite of melting. The melting point and freezing point are usually the same temperature. See the phase article for more detail.

[edit] Books

Kleinert, Hagen, Gauge Fields in Condensed Matter, Vol. II, "STRESSES AND DEFECTS; Differential Geometry, Crystal Melting", pp. 743-1456, World Scientific (Singapore, 1989); Paperback ISBN 9971-50-210-0 (readable online here)