Austenising

Following preheat the tool is austenised by heating to correct austenising temperature to obtain fine grained austenite in which carbides are dissolved.

Quenching

The austenised tool is quenched in brine, water, oil, air or molten salt bath depending upon the hardenability and thickness of cross-section. The correct rate of cooling will decide the quenching media and cooling faster than the correct rate will result in under stresses. The distortion of tools in more conveniently avoided by martempering or austempering.