Austenite (γ-phase)

Austenite (γ-phase) – is a high-temperature face-centered modification of iron and its alloys.

Austenite in carbon steels – is a solid interstitial solution where carbon atoms enter the unit cell of γ-iron during the final heat treatment. The metal atoms replace the iron atoms at crystal lattice in steels containing other metals (except iron, alloy steels).Thus solid substitutional solution appears. Austenite exists in pure iron at the temperature range of 910-1401 ° C.  Austenite exists in carbon steels at temperatures not lower than 723 ° C.