关键词: 焊接应力应变分布 , 有限元 , 数值模拟

Abstract: The development of welding stress-strain around welding pool was analyzed based on simulation on surfacing refusion of low-carbon steel sheet. The hypothesis that any cross-section retains flat when the sheet is being welded and cooled is not supported by development of relative deformation of 4 pair cross-section. The another definition of tensile strain and compression strain were put forward when the metal is heated or cooled. The data from simulation indicate that, to any point, the sum of the max compression strain and the max tensile strain, which amplitudes are larger than thermal strain, is equal with residual total strain. It couldnt prove that plastic strain is the token of metal status, compressed or stretched when it is affected by heat. The final distribution of compression strain couldnt be determined on the cross-section with max width welding pool. The result shows that the longitudinal residual stress is higher than yield strength of base metal at room temperature where the max plastic strain exceeds 0.2% and that the residual plastic strain is about 0.2% at the same zone.

Key words: Distribution of welding stress and strain , Finite element , Numerical simulation.