通过显微硬度计、拉伸试验机、扫描电镜和X射线衍射仪等研究了激光填丝焊接6 mm厚6061铝合金接头的显微组织和力学性能。结果表明：焊缝中心区域的显微组织为等轴晶，由α-Al固溶体组成，无β（Mg₂Si）强化相析出，近熔合区的焊缝组织为柱状晶；焊接接头焊缝的硬度最低，约为73 HV，母材的硬度最高，约为110 HV，随着距焊缝中心距离的增大，热影响区的硬度先呈波浪式增大，在距焊缝中心2.2～3.8 mm处有所下降，此外为热影响区软化区，在距焊缝中心3.8～4.4 mm处又快速增大；焊接接头的抗拉强度为234 MPa，约为母材的71%，高于熔化极惰性气体保护焊接接头的；焊接接头均在焊缝处断裂，接头与母材均为韧性断裂。

6061 aluminum alloy with thickness of 6 mm was welded by laser welding with filler wire. The microstructure and mechanical properties of the welded joint were studied by micro-hardness and tensile testers, scanning electron microscope and X-ray diffractometer. The results show that the microstructure of weld center was equiaxial grains composed of α-Al solid solution and no β(Mg₂Si) strengthening phase was found. The microstructure of the weld near fusion zone was columnar grains. The hardness of the weld in the welded joint was the lowest of 73 HV and that of base metal was the highest of 110 HV. With the increase of the distance from the weld center, the hardness in heat affected zone increased first in a wave mode, then decreased at the position located at 2.2-3.8 mm from the weld center, namely the softening zone in heat affected zone, and finally increased rapidly at the position located at 3.8-4.4 mm from the weld center. The tensile strength of the welded joint was 234 MPa, 71% of that of the base metal and higher than that of metal inert-gas welding joint. The welded joint both fractured at the weld and both the joint and base metal fractured in ductile mode.