基于名义应力法的疲劳卡片构建方法研究

基于有限元的疲劳寿命预测可应用于各行业,疲劳寿命预测精度的提高,离不开有效的材料疲劳卡片,疲劳卡片反映了载荷水平与疲劳寿命的关系。通过设计合理的材料试样的疲劳试验,结合试验与有限元计算,计算不同损伤参量创建应用于疲劳寿命分析的材料疲劳卡片,同时对疲劳卡片的仿真精度进行了验证。结果表明,基于名义应力法构建的疲劳卡片具备较高的预测精度,结合材料试验数据与仿真结果构建的多应力比S-N疲劳卡片,可用于其他适用于应力疲劳分析的零部件疲劳寿命分析,为提高零部件疲劳寿命预测精度提供新的技术途径,为零件的前期结构设计提供参考,可在不同领域进行推广并开展进一步分析研究。

Research on Fatigue Card Construction Based on Nominal Stress Method

Fatigue life prediction based on finite element analysis can be applied in various industries. The improvement of fatigue life prediction accuracy is inseparable from effective material fatigue cards, which reflect the relationship between load level and fatigue life. In this paper, the fatigue tests were combined with finite element simulation to determine different damage parameters for the reasonably designed material samples, and then the material fatigue card in fatigue life analysis was created. The simulation accuracy of the fatigue card was verified as well. The results show that the fatigue card constructed based on the nominal stress method leads to higher prediction accuracy.The multiple stress ratio S-N fatigue card constructed by combining the material test data with simulation results can be used for fatigue life analysis of other parts suitable for stress fatigue analysis.The paper presents a new method to improve the fatigue life prediction accuracy and provides a reference for the early structural design of components.