盲孔法测量921A钢焊接残余应力的应变释放系数研究

根据盲孔法测量残余应力的基本原理和孔边塑性变形修正方法，分别对盲孔法测量921A钢焊接残余应力时的应变释放系数A、B进行实验标定，通过试验得出了921A钢盲孔孔边塑性变形对测量精度的影响和盲孔法测量921A钢焊接残余应力的塑性修正公式；并对实验标定应变释放系数与通孔应变释放系数理论解进行比较，表明试验结果与通孔应变释放系数理论值有较好的一致性，测量结果经塑性修正，最大误差减小到2．5％以下，试验结果可以直接在盲孔法测量921A钢焊接残余应力工程实际中应用。

Research on Measuring Strain Relief Parameters of Welding Residual Stress of Steel 921A by Blind-hole

Strain relief parameters A and B of welding residual stress of Steel 921A measured by blind hole method are verified by test. In the test, it is found that the plastic deformation around the blind hole exerts influence on measurement precision. A plastic correction formulation for 921A welding stress measured by blind hole method is developed. The test results are compared with the theoretical calculation results of the strain relief parameters of the hole, it shows that the two results are in good coincidence. The largest measurement error is reduced to no more than 2.5%. The test results can be directly used in welding residual stress measurement of Steel 921A.