为了建立精细有限元模型，提高焊缝疲劳寿命仿真预测精度，需准确获取焊缝区的组织及材料力学性能分布.通过金相试验得到了焊缝区域组织分布，结合硬度试验和经验公式获取了焊缝微小区域组织应力应变曲线参数.根据试验结果分析提出一种焊缝分区建模方法，并利用准静态拉伸试验验证了该方法的正确性，为进一步分析焊缝区域失效机制以及预测疲劳寿命奠定了基础.
Locking caps are widelyused components in large engineering projects such as nuclear reactors and mining machines. In order to improve the precision of weld FE model and fatigue life prediction, it is required to obtain accurate microstructure and mechanical properties of the weld zone. In this research,the microstructure performance was studied by metallography, combined with hardness test and empirical formula to obtain stressstrain parameters of small regional organizations of the weld. Based on this, a partitioned seam weld modeling method was developed. The method was verified by quasistatic tensile test and lays the foundation for further analysis of failure mechanism and fatigue life prediction of weld zone.
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