Investigation of very high cycle fatigue behavior of TC17 alloy

According to the loading characteristics of engine blades, a vibration bending fatigue system by using the ultrasonic fatigue test technique has been developed and the specimen is designed by finite element method, fatigue tests of TC17 between 10(6) and 10(9) cycles have been completed in this paper. The results show that the fatigue life of specimen increases over 10(7) cycles and the initiation of fatigue cracks transfers from only in the surface of specimen to both in the surface and the sub-surface with loading decreasing.