Abstract
In order to clarify the appearing coaxing effect for interior inclusion induced fracture mode of bearing steel in rotating bending. Two step loading and step-wise increase loading tests were carried out using hour-glass shaped specimens in the ordinary room atmosphere. From the experimental results, interior inclusion induced fatigue life was almost equal to one of uniform loading tests. It seems that coaxing effect was not appeared against the interior inclusion induced fracture mode. Based on fracture mechanics, stress intensity factor range at the front of fine granular area (FGA) was almost same value to one of uniform loading test. But in the case of the increase loading in the beginning of fatigue, FGA size was smaller than others.
