中文摘要：

以2mm厚6056铝合金为试验材料，采用激光双侧填丝焊接方法进行铝合金T型接头焊接工艺试验，主要研究了光束入射角度、光束入射位置、送丝速度与焊接速度等工艺参数对焊缝成形的影响；分析了T型接头焊缝的显微组织特征与拉伸性能。试验结果表明：光束入射角度过大时，两侧焊缝重合面积较小且蒙皮热变形较大；当光束入射位置偏移立筋0．2～0．3mm时可以显著改善蒙皮背部的热变形。焊缝中心组织与两侧无明显差别，均为细小的等轴晶。焊缝熔深是T型接头拉伸载荷的重要影响因素，接头起裂于蒙皮焊趾处，断裂于焊缝与母材金属之间的熔合区。

英文摘要：

The experiment of both-side laser beam welding with filling wire of T-joint aluminum alloy was carried out. The effects of beam incident angle and position, wire feed speed and welding speed on the weld appearance were investigated. The microstructure characteristic and tensile property of T-joint were analyzed. The experimental results show that the weld appearance was most influenced by the beam incident angle and position. It indicated that the weld overlap area was small and the skin distortion was serious when the laser incident angle was in high level. The skin distortion was small when the laser position deviated 0.2-0.3 mm on the vertical board. The weld microstructure was equiaxed grains and had no significant difference between weld center and edge. The fillet weld penetration was the key controlling factors of T-joint tensile load. The specimen failed at weld toe, and fractured along the fusion layer between base metal and weld metal.