Austemper

Austempering

This is the term used to describe the treatment of a through hardening ferrous metal in which the cooling is interrupted above the Martensite transformation temperature and held until the transformation is completed at that temperature, usually in a molten salt bath. This produces a Bainitic structure which when compared to conventional quenching results in a softer, more ductile component with distortion minimised which usually requires no further tempering treatments.

This process has been applied very successfully to certain hardenable cast irons often referred to as Austempered Ductile Iron (ADI).