Austenite

Austenite is iron but in a metallic form. It is one of the allotropes of iron, which means its physical form is different from iron, but its chemical form is the same. It is named after Sir William Chandler Roberts-Austen (1843–1902).
Austenitization.
Austenitization means to heat iron, iron-based metal, or steel to a high temperature. At that temperature, the crystal structure of the metal changes from ferrite to austenite, which can dissolve more carbon.
For some irons, iron-based metals, and steels, the presence of carbides may occur during this austenitization step. The term commonly used for this is two-phase austenitization.