【摘要】 建立了对接多道焊热力耦合有限元模型，采用热弹塑性法对多道焊接过程中Q235钢板的残余应力进行了数值模拟；通过腐蚀剥层结合磁各向异性法测试残余应力，对模拟结果进行了试验验证。结果表明：模拟和试验得到在垂直焊缝路径上对接多道焊后钢板的表面和不同深度处的残余应力均呈“W”型分布；在平行焊缝方向上沿焊接方向，残余应力先增大后减小；随着深度增加，残余应力减小，在7 mm深度附近由拉应力转变为压应力。残余应力的模拟结果和试验结果吻合，平均相对误差为8.73%，验证了所建模型的准确性。焊接残余应力峰值不仅出现在钢板表面，也显著分布于表面以下3 mm深度范围内。随着焊道数量增加，每道次焊接后钢板内部的残余应力峰值呈下降趋势，完全冷却后局部拉应力峰值出现回升。更多还原

【Abstract】 A thermo-mechanical coupling finite element model for butt multi-pass welding was established, and the welding residual stresses in Q235 steel plate during multi-pass welding were numerically simulated using the thermoelastoplastic method. The simulation results were experimentally validated using the corrosion delamination method combined with the magnetic anisotropy method to measure residual stresses. The results show that both the simulated and measured residual stresses on the surface and at different depths along the path perpendicular to the weld seam exhibited a "W"-shaped distribution. Along the path parallel to the weld seam in the welding direction, the residual stress first increased and then decreased. With increasing depth, the residual stress decreased, transitioning from tensile to compressive stress near the depth of 7 mm. The simulated residual stresses agreed well with the experimental results, with an average relative error of 8.73%, which verified the accuracy of the established model. The peak welding residual stress occurred not only on the steel plate surface but also significantly within the subsurface region up to a depth of 3 mm. As the number of weld passes increased, the peak residual stress inside the plate decreased after each pass, and after complete cooling, the peak tensile stress showed a partial recovery in localized areas.更多还原