austenitization AmE , także: austenitisation BrE

The term commonly used for this is two-phase austenitization.

An incomplete initial austenitization can leave undissolved carbides in the matrix.

By changing the temperature for austenitization, the austempering process can yield different and desired microstructures.

For some irons, iron-based metals, and steels, the presence of carbides may occur during the austenitization step.

Austenitization means to heat the iron, iron-based metal, or steel to a temperature at which it changes crystal structure from ferrite to austenite.

A higher austenitization temperature can produce a higher carbon content in austenite, whereas a lower temperature produces a more uniform distribution of austempered structure.

The amount of time spent at this temperature will vary with the alloy and process specifics for a through-hardened part the best results are achieved when austenitization is long enough to produce a fully austenitic metal microstructure (there will still be graphite present in cast irons) with a consistent carbon content.