LF6铝合金搅拌摩擦点焊

Friction stir spot joining of LF6 Al alloy

搅拌摩擦点焊(FSSJ)是近年来发明的新的点焊方法,具有接头强度高、能耗低和设备简单等优点,在汽车行业焊接轻质合金如铝合金、镁合金等具有很好的应用前景。采用自行设计的搅拌头对1mm+1mm的LF6铝合金进行了搅拌摩擦焊试验研究。试验结果表明,接头剪切强度约是电阻点焊的1.56倍。接头可以分为搅拌区和热影响区,搅拌区的材料受到搅拌头的作用发生圆周运动和轴向运动,形成细小的再结晶晶粒,强度高、塑性好。

Friction Stir Spot Joining(FSSJ) is a revolutionary joining method which was developed in 2001. FSSJ has many advantages over conventional resistance spot welding (RSW) such as high quality and high strength, conserving energy and reducing cost, simple system, etc. which it will be widely used in automotive industry for welding of lightweight alloy such as aluminum alloy and magnesium alloy. FSSJ of LF6 Al alloy with 1mm thickness was studied by using the self - designed joining tool. The results show that the shear strength is as 1.56 times as RSW joint. The joint can be divided into stir zone and heat affected zone, and the material in the stir zone acted in both rotational and axial direction and formed the small re-crystallized grain, which had better strength and ductility.