2219铝合金焊接残余应力分布分析

Study on residual stress distribution of 2219 aluminum alloy

采用压痕应变法对2219-T87铝合金摆动TIG焊焊接残余应力进行测量,测试点分布于距焊缝中心线19和44 mm的纵截面及焊缝中心横截面.铝合金熔焊焊缝及近缝区残余应力处于拉应力状态,且应力绝对值较高.采用参数估计和假设检验方法分析沿焊缝方向近缝区纵向残余拉应力分布形式,并探究预测残余拉应力值的方法.结果表明,近缝区纵向残余拉应力呈正态分布;回归拟合和Masubuchi公式与试验数据拟合良好,均可用于预测2219-T87铝合金近缝区纵向残余拉应力值.

The indentation-strain method was adopted to measure residual stress of 2219-T87 high strength aluminum alloy sheets with arc-swing TIG welding,the measurement points were arranged at the longitudinal sections that had a distance of 19 and 44 mm to the center of welding line. The residual stress are rather larger in the welded beam zones and the adjacent zones,and are tensile residual stress. In this paper,regression analysis and hypothesis testing were used to analyze the distribution type of tensile residual stress in the area near the weld,and at the same time,to explore the methods predicting tensile residual stress.Measurement results showed that tensile residual stress has a normal distribution,and can be better described through the regression curve and the Masubuchi formula.