SURFACE TREATED GEAR, ITS PRODUCTION AND PRODUCING DEVICE THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a surface treated gear of low distortion having practically sufficient strength, and to provide a method and device for producing the same. SOLUTION: A steel member subjected to stock refining and machining is heated to an austenitic temp. region of 850 to 900 deg.C in a heating device 2 and is held in the temp. region for >=1 hr, in the process of the holding, carburizing gas only or a gaseous mixture of carburizing gas and ammonia is introduced into a furnace, and, after this holding, it is subjected to quench hardening, e.g. by a press quenching device 3.