Monitoring the Residual Stress Evolution of a Spiral Bevel Gear During its Manufacturing Steps

Nowadays, it is generally recognized by the members of automotive industry that residual stress can have notable effect on the products’ quality and/or lifetime. Because of that, more and more attention is paid to get to know the residual stress states of the automotive components in the final state and during the manufacturing processes as well. In this paper the residual stress state variation of spiral bevel gears were examined after the main manufacturing steps. The residual stress was measured at two critical locations, the tooth tops, and the axle, where the occasional fracture of the components occurred. Owing to the non-destructive type of the applied residual stress measurement technique, the measurements were performed on the same components after the manufacturing steps. Based on the results, the occasional bending and fracture of the components were connected to the stress asymmetry arisen in the components after hardening heat treatment.