Aluminum alloy 6061(AA6061) sheets of 4 mm in thickness are joined by laser wire-filling welding (LWFW) using the ER4047 welding wire. Microstructure and alloy element distributions near the fusion line are characterized and are investigated by optical microscope, scanning electron microscope, energy dispersive spectrometer. The results showed that the well-formed welded joints are obtained with a few thermal cracks near the fusion line. The coarse grain and a reduction in the weight ratio of magnesium to silicon can be observed, when the welding speed decreases under constant laser power. The thermal crack is caused by the decrease of the weight fraction of magnesium and the proportion of silicon content has an effect on the microhardness of welded joints. By properly controlling the welding speed, the various properties of AA6061 LWFW joints can be balanced.

中文翻译：

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激光填丝焊铝合金6061熔合线附近组织及合金元素分布

使用 ER4047 焊丝通过激光填丝焊接 (LWFW) 连接 4 mm 厚的铝合金 6061(AA6061) 板。采用光学显微镜、扫描电镜、能谱仪等手段对熔合线附近的显微组织和合金元素分布进行了表征和研究。结果表明，焊接接头成形良好，在熔合线附近有少量热裂纹。当在恒定激光功率下焊接速度降低时，可以观察到粗晶粒和镁与硅的重量比降低。热裂纹是由于镁的重量分数降低而引起的，硅含量的比例对焊接接头的显微硬度有影响。通过适当控制焊接速度，