Preliminary Discussion on Torsional Fretting Multi-impact Fatigue Failure

Two reducers with power of 2986 kW that used 2 and 10 years respectively, failed successively due to surface peeling and fracture of high-speed shaft. After appearance observation and macro fracture analysis, it is believed that the failure of the two reducers’ high-speed shafts is caused by fretting wear, fretting impact and fatigue damage, which is a very rare shaft-hub fatigue failure mode. The failed shaft does not fracture, but the deep circular fatigue peeling along the shaft. The fracture failure shaft has very complex fracture morphology, so it is difficult to analyze the cause of the fracture. The peeling and fracture failure mode of the shaft can not be explained theoretically. In this study, the failure mode of the above two fractures is called the torsional fretting multi-impact fatigue. There is no relevant research reported at home and abroad. It is necessary to further study and discuss the causes and failure mechanism of torsional fretting multi impact fatigue failure, thus propose corresponding preventive measures.