焊接速度对304L钢薄板激光焊接接头性能的影响

Effect of welding speed on the properties of laser welding joint of 304L steel sheet

通过0.4mm厚304L钢薄板的激光焊接试验,研究了焊接速度对焊接接头宏观形貌、硬度分布以及拉伸性能的影响。结果表明:在设定的5种焊接速度(200、250、300、350、400mm/min)下获得的焊缝熔宽均较为均匀,焊接接头均为全熔透状态,熔宽随着焊接速度的提高而减小;焊接接头硬度均大于母材且其横截面分布趋势都呈M形,焊缝区硬度随焊接速度的提高而增大;拉伸试样均于焊缝区断裂,其抗拉强度、屈服强度、断后伸长率随着焊接速度提高而增大,但都小于母材性能,当焊接速度为400mm/min时,焊接接头的拉伸性能最佳。

Based on the laser welding experiment of 0.4 mm thick 304L steel sheet,the effects of welding speeds on the macroscopic morphology,hardness distribution and tensile properties of the welded joint were compared.The results show that the weld widths obtained at the five welding speeds(200,250,300,350,400 mm/min)are relatively uniform,the welded joints are fully penetrated,and the weld width decreases with increasing welding speed;the joint hardness is larger than the base metal and its cross-section distribution.The trend is M-shaped,the hardness of the weld zone increases with the increase of welding speed;the tensile specimens are broken in the weld zone,and the tensile strength,yield strength and elongation after fracture increase with the increase of welding speed.However,they are all less than the properties of the base metal.When the speed is 400 mm/min,the tensile properties of the welded joint are the best.