TRIP980钢板激光焊接工艺研究

Study on laser welding technology of TRIP980 steel plate

采用不同焊接工艺对TRIP980钢板进行激光焊试验,研究了激光功率及焊接速度对接头宏观组织及力学性能的影响。结果表明:随着激光功率的增大,焊缝熔深逐渐增加直至完全焊透,此时接头强度先提高,之后保持稳定,断裂位置由焊缝过渡为母材,当功率过大时将产生严重飞溅,恶化焊缝性能,导致拉伸时沿焊缝开裂。随着焊接速度的提高,飞溅开始严重,导致接头强度较低,沿焊缝开裂,之后飞溅减小,接头强度提高且保持稳定,并沿母材断裂,继续提高焊接速度,焊缝熔深减小,接头强度降低,且沿焊缝处断裂。对于本研究钢板焊接合理的热输入为:33 333~50 000 J/m。

TRIP980 steel sheets were laser welded by different welding procedures.The effects of laser power and welding speed on the macrostructure and mechanical properties of the welded joint were studied.The results showed that with the increase of laser power,the weld depth increased gradually until the full penetration.At this time,the tensile strength of the welded joint increased first,then kept stable,and the fracture location transited from weld metal to base metal.When the laser power was too high,serious spatter occured,which deteriorated the weld performance and led to cracking along the weld metal during tensile tests.With the increase of welding speed,first the splash was serious,which caused the low joint strength and cracking along the weld metal.Then with the decrease of the spatter,the joint strength increased and kept stable,and the welded joint failed along the base metal.Continuing to increase the welding speed,the weld depth and joint strength decreasd,and the welded joint failed along the weld metal.For the TRIP980 steel sheets used in this study,the proper welding line energy was in the range of 33333~50 000 J/m.