Abstract
Surface fatigue failure in gear teeth has been studied since a long time ago. Surface durability in carburized gears was controlled by occurrence of Spalling. However, recent researches have confirmed the occurrence of Micropittings and Flakings at carburized gears. These failures occur with lower load than Spalling does and also lead to tooth breakage. This paper focused on surface durability test of carburized gears, using the power circulating test rig. Micropittings occurred at beginning of the experiment and its number increased as the number of cycles increased. Flaking occurred after accumulation of Micropittings, and some cracks were also observed before Flakings occurrence. Based on failure process observation, we can conclude that is possible to create ten levels for failure rank in order to identify and classify failure situation on gear teeth.
