Precision components such as industrial bearing races and automotive gears often distort unpredictably
during heat treatment due to the deleterious effects of free or unconstrained oil quenching. Press
quenching is a method that can be utilized to minimize the distortion of these complex components during
heat treatment. This is accomplished in a quenching machine by utilizing specialized tooling for
generating concentrated forces to constrain the movement of the component during oil quenching. When
performed correctly, this method of quenching can often achieve the relatively stringent geometrical
requirements stipulated by industrial manufacturing specifications. It can be performed on a wide variety
of steel alloys. These include high carbon through-hardening grades such as AISI 521 00 and A2 tool
steel, as well as low carbon carburizing grades such as AISI 331 0, 8620, and 931 0. The relevant aspects
of this specialized quenching technique will be presented together with a case study of the effects of prior
thermal history on the distortion that is generated during press quenching.