镍箔中间层对不锈钢/铝合金激光深熔焊的影响

以不锈钢201和铝合金5052作为试验材料，添加镍箔作为中间层，配合钢上铝下的搭接接头形式，采用激光深熔焊方法进行了焊接试验，分析了热输入对焊缝成形的影响以及添加镍箔后接头力学性能与不锈钢／铝合金焊接性的变化，并提出了焊缝下凹深宽比r以表征焊缝对应力集中的敏感程度．结果表明，热输入升高会导致焊接过程中飞溅增加，焊缝宽度与下凹程度增大，熔穿深度升高；不锈钢焊缝金属嵌入到铝合金内的熔穿深度对焊缝的力学性能有着重要的影响；镍中间层的添加有效地改善了接头力学性能，扩大了可用的工艺参数范围．

Influence of Ni-foil interlayer on laser penetration welding of stainless steel to aluminium alloy

Laser penetration welding of type-201 stainless steel and type-5052 aluminium alloy was investigated with nickel foil as the interlayer.Lap joint was applied with steel sheet on the top and aluminium sheet at the bottom.The effect of heat input on weld forming was studied,and the mechanical properties of the joints and weldability of stainless steel and aluminium alloy with addition of nickel foil interlayer were analyzed.The ratio of weld concaved width to penetration was put forward to represent the sensitivity of stress concentration.It was found that increasing heat input resulted in aggravating weld spatter and increasing of weld width,weld concaved width and penetration.The penetration depth of the weld into aluminium alloy had significant influence on the mechanical properties of the joint.The addition of nickel foil interlayer improved the mechanical properties of the resultant joints and extended the range of operable welding parameters.