Abstract
This study examined fatigue properties of tempered steel that used the super rapid induction heating technology. The experiment used the hollow specimen to ignore the residual stress generated by the induction hardening and to extract the property only of the tempering microstructure. As a result, the following conclusions could be summarized. (1) The precipitates in the super rapid induction tempered steel were finely dispersed than the furnace tempered steel. (2) The fatigue life showed almost the same tendency without relation to the hardness and tempering condition. (3) As for the fatigue limit in 450HV, the improvement effect by the super rapid induction tempering was recognized.
