光束偏移量对钛/铝异种合金激光焊接接头组织和性能的影响  

Influence of laser offset on microstructure and mechanical properties of Ti/Al dissimilar joint by laser welding

作　　者：宋志华[1] 吴爱萍[1] 姚为[2] 邹贵生[1] 任家烈[1] 汪永阳[2] 

机构地区：[1]清华大学先进成形制造教育部重点实验室,北京100084 [2]北京航星机器制造公司,北京100013

出　　处：《焊接学报》2013年第1期105-108,118,共4页Transactions of The China Welding Institution

摘　　要：采用激光进行3 mm厚钛合金TA15和铝合金5A06的对接焊,激光束聚焦在钛合金上使钛合金熔化,通过热传导使铝合金熔化,得到了成形良好的接头,分析了光束偏移量对接头组织和性能的影响规律.偏移量为0.1～0.4 mm时,形成了熔焊接头.偏移量为0.5 mm时,接头上部形成熔焊接头,并形成了Ti-Al金属间化合物.接头中部和下部形成了熔钎焊接头,并形成了一层连续的约1μm厚的金属间化合物.接头抗拉强度随偏移量的增加先增大后减小,偏移量为0.5 mm时,接头强度最大,平均抗拉强度可达到181 MPa,接头部分断裂于钛/铝界面的金属间化合物处,部分断裂于铝合金焊缝区.Laser welding of TA15 and 5A06 alloys with 3 mm in thickness was conducted by focusing laser beam on titanium side,and the aluminum was melted through the heat conduction from titanium side.The effect of laser offset distance on microstructure and mechanical properties of the dissimilar butt joint was investigated.When the laser offset is 0.1-0.4 mm,fusion welded joint is formed.When the laser offset is 0.5 mm,fusion welded joint is formed on the upper side of the joint accompanying with Ti-Al intermetallic compounds.Welded-brazed joint is formed on the middle and bottom side of the joint accompanying with continuous Ti-Al intermetallic compounds layer with 1 μm thickness.The tensile strength of joints firstly increased and then decreased with the laser offset increasing.The highest average tensile strength of the joint reaches 181 MPa when the laser offset distance is 0.5 mm.The joints partly fracture in Ti-Al intermetallic compounds at the interface,and partly fracture at the fusion zone of aluminum alloy.

关 键 词：钛合金 铝合金 激光焊接 接头组织 接头性能 

分 类 号：TG456.7[金属学及工艺—焊接]