抄録
The measurement of hardened layer and the impact tests were carried out for gas and vacuum case-carburized SNC815 steel gears and induction hardened gears made of thermally refined and as-rolled S35C steels. The effective hardened depth (HV400) and the case depth (HV550), the relation between impact energy and the increment of sector span of test gears were obtained. Relationships between the hardened depth, the case depth and the impact strength of case-carburized and induction hardened gears were examined, and the method for selecting the suitable case-carburizing and induction hardening condition for impact strength was proposed.
