研究经过度变形得到的超细晶粒钢 Q2 3 5的激光焊接特性。结果表明超细晶粒钢在激光焊时会因形变晶粒发生再结晶而在接头中出现软化区 ,区域大小受焊接工艺参数的影响 ,高激光功率和高焊接速度可以产生很窄的再结晶区 ,从而使接头强度高于母材。拉伸试样断口形貌属延性断裂 The laser welding characteristics of the ultrafine grained Q235 steel after deformation were studied. The results show that the ultrafine grained steel will recrystallize in the laser welding and appear in the joint softening zone, the size of the area affected by the welding process parameters, high laser power and high welding speed can produce very narrow recrystallization Zone so that the joint strength is higher than the base metal. Tensile specimen fracture appearance is ductile fracture