2219铝合金复合热源焊接工艺及接头性能

Welding process and joint properties of hybrid welding on 2219 aluminum alloy

采用填丝TIG焊、激光辅助TIG复合焊、激光-高频脉冲TIG复合焊三种焊接工艺进行6 mm厚的2219铝合金焊接试验,研究了焊接工艺与接头组织和性能的相关性.结果表明,与填丝TIG焊接工艺相比,激光辅助TIG复合焊、激光-高频脉冲TIG复合焊两种复合热源焊接工艺提高了焊接速度,显著减少了热输入,细化了焊缝组织,减少了晶界共晶组织的宽度,尤其能有效消除焊缝熔合区的气孔缺陷,并且显著改善和提高了焊接接头的力学性能和抗应力腐蚀性能.激光-高频脉冲TIG复合焊接头SCC断裂时间明显提高,达到了母材的93%.

The correlation between three welding processes and joint microstructure as well as properties was investigated on 2219 aluminum alloy of 6 mm thickness.The three welding processes were TIG welding with filler wire,low-power laser assisted TIG hybrid welding and laser high-frequency pulse TIG hybrid welding respectively.The results showed that,compared with the TIG welding,the hybrid welding processe could improve the welding speed,reduce the heat input significantly,refine the microstructure of the joint,and reduce the width of eutectic α(Al)+θ(CuAl2),especially eliminate the porosities of fusion zone effectively.Furthermore both the joint properties and stress corrosion resistance were improved significantly.The average fracture time for 2219 aluminum alloy through the laser high-frequency pulse TIG hybrid welding was significantly longer than that through the TIG welding,which was about 93% of the average fracture time for 2219 base material.