最大主应力预测点焊疲劳寿命研究

摘要: 采用基于最大主应力的点焊疲劳寿命预测方法对拉剪受力状态下的电阻点焊疲劳寿命进行有限元模拟。使用壳单元、CWELD点焊连接单元建立点焊有限元模型，利用商业有限元软件Nastran进行线弹性分析。通过对比分析线弹性有限元分析结果、焊接接头疲劳试验数据，拟合出基于最大主应力的点焊疲劳寿命S-N曲线，并依据拟合的S-N曲线和有限元分析取得的最大主应力预测不同载荷水平下的点焊疲劳寿命。疲劳寿命预测结果与疲劳实验结果对比表明，不同载荷下的点焊疲劳寿命预测结果与实验寿命有良好的一致性。
- 点焊 /
- 有限元分析 /
- 最大主应力 /
- 疲劳寿命 /
- 疲劳试验
Abstract: The authors use major principal stress around the weld nugget of spot welding to predict fatigue life for spot welded joints in automotive body structures. The finite element model for spot welding specimens are established by using shell and CWELD elements. The stress field in the spot welding specimens is analyzed via Nastran software. Based on the computed major principal stress, the fatigue life is estimated by using the S-N curve which is from linear fitting based on the finite element analysis and fatigue test data of spot welding. The calculated fatigue life for spot welding is compared with the experimental to verify the validity of the calculation method. The used method is proven an effective in consolidating a series of fatigue data for spot welding subjected to tensile shear load.
- spot welding /
- finite element analysis /
- major principal stress /
- fatigue life /
- fatigue experiment

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参考文献(15)

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