METHOD FOR HEAT-TREATING A RING-SHAPED MEMBER, METHOD FOR PRODUCING A RING-SHAPED MEMBER, RING-SHAPED MEMBER, BEARING RING, ROLLING BEARING, AND METHOD FOR PRODUCING A BEARING RING

摘要

Disclosed is a method for heat-treating a ring-shaped member, which makes it possible to form a quench-hardened region having a uniform annular shape in the circumferential direction, while the production costs in terms of the quenching apparatus are kept down. The method includes the following steps: a step in which a coil (21) which is disposed in such a way as to face a rolling contact surface (11) of a ring-shaped formed body (10) made of steel and which performs induction heating of the formed body (10) is rotated relative to the formed body (10) in the circumferential direction thereof, whereby an annular heating region which is heated to a temperature at or above an A 1 point is formed on the formed body (10); and a step in which the whole of the heating region is simultaneously cooled to a temperature at or below an M s point.