进给速度对铜界面合金化镁/铝FSW组织与性能的影响

Influence of Feed Speed on the Microstructure and Mechanical Properties of the Magnesium-Aluminum Interface Alloying Joint with Cu Foil by Friction Stir Welding

研究了不同进给速度对AZ31B镁合金/5052铝合金铜界面合金化搅拌摩擦焊焊接接头组织与性能的影响。结果表明,在进给速度为200mm/min时接头的抗拉强度最低,在进给速度为100mm/min和300mm/min时焊缝的抗拉强度较好;随着添加铜箔的厚度增加,焊接接头的抗拉强度先增加后降低。在进给速度为100mm/min,铜箔厚度为0.05mm,旋转速度为1 200r/min时能得到良好的焊接接头,其最大抗拉强度为87.5 MPa;加入铜箔后,接头处生成了Mg_2Al_3、Mg_(17)Al_(12)、AlCu、Al_2Cu、MgCu_2相,无明显焊接缺陷,硬度分布近似成"M"形。

The effects of varied feed speed on the microstructure and properties of AZ31B magnesium alloy/5052 aluminum alloy interface alloyed friction stir welding joints with Cu foil were investigated.The results reveal that the tensile strength of the joint presents the lowest value with the feed speed of 200mm/min,and it is satisfied with 100mm/min and 300mm/min.As the thickness of the added copper foil increase,the tensile strength of welded joint is increased firstly and then decreased.With the feeding speed of 100mm/min,the 0.05mm thickness of copper foil and the rotation speed of 1 200r/min,the desirable welding joints can be obtained,and the maximum tensile strength can reach 87.5 MPa.With the copper foil,Mg2Al3,Mg（17）Al（12）,AlCu,Al2Cu and MgCu2 phases are generated at the joint junction without obvious welding defects,and hardness distribution shows approximately＇M＇shape.