If customer’s specification demands to stay below a certain level of retained austenite, a deep freezing operation can be performed after heat treatment.
Retained austenite is critical for some components, since it may transform during application into martensite, which will lead to deformation of the parts. E.g. for some aerospace components or for some fuel injection components all retained austenite must be eliminated.
ALD’s HTS division offers deep freezing with liquid nitrogen at temperatures of -80°C.