The 42CrMo4 type of steel is used for tempering and quenching, in part because it has such a good combination of toughness and strength in the tempered and quenched condition. Once the oil quenching is complete, the steel itself will be through-hardened up to ø60 mm bar diameter. The steel itself is applicable to induction hardening. This is a special high-grade steel that provides a great amalgamation of both toughness and strength, and it is usually available in a mix of microstructure, that is, austenite and martensite. There are different European standards that cover the specification of the steel in various forms and processing conditions. The special grade of this steel is always subjected to M-treatment to provide the best machinability properties.