含铒铝合金激光焊接接头组织与性能研究

对含铒铝镁合金冷轧板进行了激光焊接,分析了接头的各区域的微观组织和力学性能,探讨了铒对焊缝及热影响区组织与性能的影响。结果表明:由于稀土元素Er的加入,使焊缝中心晶粒尺寸减小到30μm左右;熔合线附近出现"细晶层";热影响区晶粒未见明显长大;焊接接头焊缝截面的显微硬度呈W形分布;Er对焊接接头的抗拉强度提高并不明显,接头抗拉强度为母材的70%。

Research on Microstructure and Properties of Er-containing Aluminum Alloy Laser Welded Joints

The Er-containing Al-Mg alloy was welded by laser beam welding.Microstructures and mechanical properties of the joints were analyzed,and the effects of erbium on the microstructure and properties of the weld and the heat affected zone were investigated.The results show that due to the addition of rare earth element Er,the grain size of the weld center reduces to about 30 μm;a "fine grain layer" appears near the fusion line;no significant grain growth occur in the heat-affected zone;the micro-hardness in the cross section distributes in W-shape.The effect of Er on the tensile strength of welded joints is not obvious,and the tensile strength is 70% of that of the base material.