S111034 Bending Fatigue Strength of Re-hardened Gears after Poor Induction Hardening

Abstract

In some cases where there is the deterioration of the vacuum tube oscillation in the induction hardening apparatus, poor hardened gears are usually produced by the induction hardening apparatus of deteriorated vacuum tube oscillation. Such poor hardened gears may be improved by re-hardening with the induction hardening apparatus of new vacuum tube oscillation. In this paper, measurements of the profile, the hardness and the micro-structure of hardened layer and the bending fatigue test were earned out for the poor induction hardened gears and the re-hardened gears. The validity of the re-hardening treatment for the poor induction hardened gear was determined to a considerable extent.