Single cycle, single frequency induction contour hardening process

摘要

The present invention discloses a method for contour hardening a gear by means of induction heat treatment in a single heating cycle, using a single frequency of induction current. The typical frequency of alternating current is 50 KHz, applied in a single heating cycle for a duration in the general range of 0.3-1.0 seconds, having a power in the typical range of 200-1,000 KW. The power level required for any particular gear is typically 120% to 150% that required in the final heating step of a hardening process which requires preheating. An important advantage of the process disclosed herein is the elimination of the need to preheat the gear, yet contour harden tooth and root regions of said gear with a single heating cycle of a single frequency heating current.