为了能够利用材料数据和有限元分析结果对结构件的低循环疲劳寿命进行评估,提出一种基于拉伸应变能且考虑平均应力、应力集中和尺寸效应等多种因素的寿命预测方法,并推导了不同应力比下拉伸应变能公式。采用材料手册中的数据以及已有的试验数据对该模型进行验证,寿命预测结果和试验结果一致性较好,对比局部应变法寿命预测精度大大提高。该方法预测的两类轮盘模拟件疲劳寿命均在2倍分散带之内,在工程中有较为广阔的运用前景。To evaluate the low cycle fatigue life of structural parts by using material data and finite element analysis results, a life prediction method was proposed based on tensile strain energy. This method considered multiple factors such as average stress, stress concentration and size effect. The tensile strain energy formula under different stress ratios was further derived. The data in the material manual and the existing test data are used to verify the model. The life prediction results are in good agreement with the test results, and the life prediction accuracy is greatly improved compared with the local strain method. The fatigue life predicted by this method for the two types of wheel simulators is within 2 times error band, which has a broad application prospect in engineering.
