Measurement of Residual Stresses in Welded Joints by DCP Method

Residual stresses on welded joints have been studied by several methods. In this present work, residual stresses was measured by a novel methodology under development named Displacement of Coordinated Points (DCP). To evaluate anisotropy effects in steel plates, two directions of the weld bead were considered: Welding was performed in both parallel and transversal direction of rolled steel plate ASTM A131 grade AH36.The experiments showed higher values of the residual stress in the transversal direction of the lamination when compared with the longitudinal direction, evidencing the anisotropy effect of the material. It was also observed that the increasing in heat input induces higher residual stress.

学界已通过多种方法对焊接接头的残余应力展开研究。本研究采用一种处于研发阶段的新型测试方法——协调点位移法（Displacement of Coordinated Points，DCP），对残余应力进行测量。为评估钢板的各向异性效应，本研究选取两种焊接方向开展试验：分别沿ASTM A131标准AH36级轧制钢板的轧制平行方向与轧制横向进行焊接。试验结果表明，相较于轧制纵向，轧制横向的残余应力数值更高，证实了该材料的各向异性效应。同时研究还发现，热输入量的提升会导致残余应力水平升高。