Abstract
The manufacture and performance of case-carburized gears for the high load-carrying capacity were investigated. First, the various processing steels were finished after case-carburizing and quenching treatments. Secondly, the hardness distribution of various processing steels which were given the heat pattern by using a heated oil tank was examined. In addition, surface durability of various processing steels was studied by using a 2-roller-type contact fatigue tester. In the case of the subzero treated and tempered steel, the tempered and shot peened steel, and, the subzero treated, tempered and shot peened steel, the following results are obtained : (1) The surface hardness remarkably decreases when high temperature is received. (2) The allowable contact stress for the surface fatigue lowers in comparison with the tempered steel. (3) The relation between changed surface hardness and surface durability is clarified.
