Quenching

• Quenching is a general term for non-radiative de-excitation. One major reason for non-radiative de-excitation is collisions. As a consequence is the quenching often heavily dependent on pressure and temperature. Quenching poses a problem for non-instant spectroscopic methods, such as laser-induced fluorescence.

• In materials science, quenching is the rapid cooling of a solid to lock it into a metastable crystal structure rather than allow it to cool slowly and revert to a softer structure. It is most commonly used to harden steel by introducing martensite, in which case the steel must be cooled from a temperature at which austenite is stable.