The Establishment of Fatigue Life Model of Gery Cast Iron Cylinder Heads Based on Mechanical Fatigue Tests
Fatigue is the main failure mode of engine”s complicated components like cylinder heads.Hence,an accurate life model would help direct anti-fatigue methods.However,because cylinder heads undergo complex thermal and mechanical loadings,it would be very difficult to conduct tests which can completely simulate the thermo-mechanical fatigue condition.In this study,in order to evaluate the fatigue time of cylinder heads with high efficiency,since cylinder heads” lifetimes are decided by the low cycle fatigue areas on its fire deck,this critical location should be highlighted.A near-components-shaped specimen “valve bridge sample” were designed and then tested on a one-way pull-press fatigue machine.By comparing the measured fatigue lifetimes from tests to the calculated ones from four life prediction formulas,a preferable formula was selected to establish the original lifetime model.Then,taking into account that material related parameters like yield limit would decrease under high temperature,the original lifetime model was corrected by adopting the temperature factor “t”.Finally,the availability and accuracy of the life model were validated.
cylinder head grey cast iron life model mechanical fatigue tests
Wang Hui Cheng Ying
School of Mechanical Engineering,Beijing Institute of Technology
国内会议
上海
英文
410-415
2016-10-26（万方平台首次上网日期，不代表论文的发表时间）