The calibration and correction of the strain release coefficients A and B were conducted by the combination of finite element simulation and experiments in the welding residual stress measurement of LY12 aluminum alloy sheet by the blind-hole method.By introducing the plastic additional strain,the plastic correction formula based on the relationship between the strain release coefficients and the shape-changed specific energy was obtained.In the end,the welding residual stresses of the butt welding LY12 aluminum alloy sheets were measured by the blind-hole method with the corrected strain release coefficients and the experimental results and simulation results were compared and analyzed.The results show that the maximum measurement error of the welding residual stresses reduced from 57.457% to 3.208% with the given plastic correction formula,showing the good correction effects.%采用有限元模拟与试验验证相结合的方法,对盲孔法测LY12铝合金薄板焊接残余应力时的应变释放系数A,B进行标定及修正;引入塑性附加应变,得到应变释放系数随形状改变比能参量变化的塑性修正公式,最后利用修正后的应变释放系数采用盲孔法测试了LY12铝合金对焊接接头的焊接残余应力,并和模拟结果进行了对比分析.结果表明:给出的塑性修正公式将焊接残余应力的测试误差由57.457%缩小到3.208%以内,修正效果良好.
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