一种新的多轴高周疲劳寿命预测模型

分析和讨论3种典型载荷(单轴拉压、纯扭及90°非比例)情况下的5组损伤控制参数,提出了一种以临界面上最大剪切应力幅和最大法向应力的非线性组合作为损伤控制参数的多轴高周疲劳寿命预测模型,该模型考虑了平均应力对疲劳寿命的影响,比现有的疲劳预测模型具有更宽的金属材料适用范围.两种不同类型材料下的多轴非比例试验的预测结果表明,模型的预测结果与试验符合较好.

A NEW MODEL FOR LIFE PREDICTION OF MULTIAXIAL HIGH-CYCLE FATIGUE

Several groups of fatigue damage parameters under three typical loading cases (i.e., fully reversed tensional, fully reversed torsional and 90$^\circ$ non-proportional loading) are discussed in this paper and a new life prediction model for multiaxial high-cycle fatigue is proposed. The proposed model is based on a nonlinear combination of the maximum shear stress amplitude and maximum normal stress on the critical plane defined by the plane of maximum shear stress range. A compromising solution to correct the mean normal stress acting on the critical plane is also proposed. The new model also extends the range of metallic materials. The predictions based on the presented model show a good agreement with test data.