Bainitic transformation

Cooling of cast iron or steel preferably in a salt bath from the hardening temperature to temperatures between the temperature for perlite formation and that for marteniste formation.

In this process, the material is kept isothermally in an appropriate medium in the so-called bainitic stage (s. Bainite) until the transformation is completed, and then it is cooled down to room temperature.

Additional references:
Bainitic cast iron
Perlite peak
Perlite point
Martensite point
TTT diagram
Austempering