薄板激光搭接焊缝的强度评价

摘要

针对列车车体上激光搭接焊缝需要进行强度评价的问题，采用试验和数值模拟相结合的方法研究了焊缝强度的影响因素和评价方法。采用ANSYS软件进行数值模拟，验证了断裂位置从焊缝向薄板转移的现象。结果表明：当焊缝宽度小于两板中的最小板厚时，焊缝宽度和拉剪力呈近似线性关系；当焊缝宽度超过最小板厚时，拉剪力达到最大值后不再随焊缝宽度的增加而增加；焊缝熔深和板间隙对拉剪力的影响不明显。根据建立的焊缝宽度和拉剪力关系，实现了通过无损检测焊缝宽度来评价焊缝强度的目的。%Aiming at the problem that the strength of laser overlap weld joints of train bodies should be evaluated,the influencing factors and evaluation methods for the strength of weld joints were researched with a method in combination with both experiments and numerical simulation.The numerical simulation was conducted with the software ANSYS,and the phenomenon that the break position changes from the weld joints to the thin plate was verified.The results show that when the weld width is smaller than the thickness of thin plate in two plates, the weld width and shear force approximately show a linear relationship.When the weld width is bigger than the thickness of thin plate,the shear force reaches the maximum value and does not increase with increasing the weld width.In addition,the weld depth and plate gap have no obvious effect on the shear force.According to the established relationship between the weld width and shear force,and the goal of evaluating the strength of weld joints can be realized through measuring the weld width with non-destructive testing.