Abstract
In this study, an accelerated fretting fatigue testing method by using ultrasonic torsional fatigue testing machine was developed. Fretting fatigue tests for S45C specimens by using the method were conducted. To compare with the results, the fatigue tests for smooth specimens were conducted. In the case of fretting fatigue, a crack was initiated from a fretting part. The results showed that fretting fatigue tests can be performed by using an ultrasonic torsional fatigue testing machine.