METAL MEMBER ANNEALING METHOD

摘要

In this annealing method for a metal member, a first heater that emits infrared light is arranged in the interior space of a hollow cylindrical metal member so as to extend parallel to the central axis direction of the metal member, in which multiple teeth are formed on the inner circumferential surface and protruding toward the center. The metal member is heated from the interior space by means of the first heater, and after heating the metal member is cooled slowly.