After carburizing, the work is either slow cooled for later quench hardening, or quenched directly into oil. Quench selection is made to achieve the optimum properties with acceptable levels of dimensional change. Hot oil quenching may be used for minimal distortion, but may be limited in application by the strength requirements for the product. Alternatively, bearing races may be press quenched to maintain their dimensional tolerances, minimizing the need for excessive post heat treatment grinding. In some cases, product is tempered, then cryogenically processed to convert retained austenite to martensite, and then retempered.