AMA 2019 Speakers
Prof. Minhao Zhu (Keynote Speaker)
Southwest JiaoTong University, China
Title of Speech: Damage Mechanisms of Varied Fretting Fatigue Modes
Abstract: According to the lording direction, the fretting fatigue can be divided into three basic modes: i.e. tension-compression, bending and torsional fretting fatigue. Based on a multi-axis tension-torsion fatigue testing machine platform, the tension-compression, bending and torsional fretting fatigue devices were self-designed respectively, the systematic tension-compression, bending and torsional fretting fatigue tests of 316L austenitic stainless steel, LZ50 steel and 7075 aluminum alloy were carried out on the point contact mode with cylinder/cylinder vertical cross. The fretting fatigue S-N curves were obtained. The various fretting damage zones (partial slip regime (PSR), mixed fretting regime (MFR) and slip regime (SR)) of fretting fatigue samples were analysed comprehensively by optical microscope (OM), scanning electron microscope (SEM), electron energy disperse spectroscopy (EDS), X- ray photoelectron spectrometer (XPS), electron probe microscope analysis (EPMA), transmission electron microscope (TEM) and 3-D white light interferometer. The characteristics of S-N curve, surface damage morphologies, fractographies, crack source locations, crack propagation paths, and crack initiation mechanisms were reviewed systematically. The common features for three various fretting fatigue were outlined and the special phenomena distinguish from others of each mode also has been presented. Two crack initiation mechanisms under various fretting fatigue modes for different metallic materials with different stacking fault energy have been founded.
Key words： fretting fatigue; tension-compression fretting fatigue; bending fretting fatigue; torsional fretting fatigue; fretting damage; crack initiation; damage mechanism