关键词: 切割, 焊接, 连续加工, 耦合残余应力, 应力演变, 数值模拟

Abstract: Thermal cutting and welding usually act on components orderly in shipbuilding,and the coupled residual stresses with complex distribution was induced during this process,which led to difficulty in analyzing the residual stresses distribution.To tackle this problem,the numerical calculation model for the typical process that butt welding between two plates cut by oxygen flame was studied based on thermal elastic-plastic finite element method.The distribution and evolution of coupled residual stresses were analyzed.The results demonstrated that there was a region that the tensile stress values exceeded the yield point of material along the weld seam,and the width of this region was higher than those of cutting and welding execution respectively.The stresses with longer distance away from the weld seam were not only influenced by the temperature itself,but also the compressive stresses induced by welding heat source,so it appeared as the increasing tensile stresses,and the influence of initial cutting residual stresses on the final coupled residual stresses depended on the gradient magnitude of temperature.

Key words: cutting, welding, sequential process, coupled residual stresses, stress evolution, numerical simulation