Fatigue behaviors of a titanium alloy in the VHCF regime based on a vibration‐based bending fatigue test
Xu We, Xin Chen, Zhiyuan Gao, Ying Li, Yuhuai He, Chunhu Tao
Abstract
Abstract A vibration‐based bending fatigue test based on electrodynamic shaker is conducted in order to study the high cycle and very high cycle fatigue (VHCF) behaviors of a titanium alloy TC17 with a sort of novel specimens. After obtaining a full S‐N curve covering the lifetime up to 10 9 cycles, several fatigue crack initiation and failure process modes are revealed based on the observation of the fracture surfaces. Especially, the statistical distribution characteristics of the fatigue lifetime and some relevant factors are discussed. The results indicate that the obtained S ‐ N curve does not exhibit a plateau region in the VHCF regime. And the present crack initiation mechanism involves the facets formed by the primary α‐phase cleavage and the development of microcracks. Moreover, the scatter of the fatigue lifetime can be obviously influenced by the resonance frequency range of the specimens.