榫连接结构微动疲劳寿命研究

根据航空发动机叶片和轮盘的榫连接结构接触区域的几何特性,对其微动疲劳接触问题进行了简化.通过有限元方法对简化模型进行数值计算分析,获取相应的应力、应变和位移.将临界平面法和微动损伤机理相结合,提出了一个微动损伤参量,并建立相应的微动疲劳寿命预测模型.将TC11试验件和榫连接构件的微动疲劳试验寿命与预测寿命进行比较分析.结果表明:所建立的微动疲劳寿命模型其预测结果误差分散带均在2倍因子以内.

Research on fretting fatigue life of dovetail joints

The fretting fatigue contact problem of dovetail joints between blade and disk in aero-engine was simplified due to geometric characteristic of the contact area. The stress, strain and displacement between these two contact bodies were obtained through the finite element method for numerical simulation of the simplified model. A fretting damage parameter was introduced and the research on the fretting fatigue life prediction model was carried out, based on the critical plane theory and fretting damage mechanism. The results confirm the validity of the life prediction model by comparing the estimated fretting fatigue life with the experimental life of TC11 and dovetail joints. And the errors are within 2 times of dispersion band.