Steel torsional element and method for making

摘要

A steel torsional element includes a first or shaft portion for transmitting torque and a second portion, such as a gear, for transferring torque to another machine element. The entire torsional element is carburized and quenched to a first depth to provide wear-resistance and resistance to surface compressive fatigue in the second portion for the transferring of torque to another machine element. The quenching operation also provides a strong but ductile core for both portions of the steel torsional element. The shaft portion is then induction hardened to a second and greater depth to increase the torsional strength thereof.