通过对30 mm厚的7A52铝合金轧制板材进行搅拌摩擦焊接工艺试验,对比分析了单面焊接和双面焊接两种工艺对焊接接头组织和性能的影响。结果表明:与单面1道焊接相比,双面(背部2次)焊接细化了前1道焊缝组织,消除单面焊道背部缺陷,且焊接接头各区的硬度趋于均匀一致,基本达到母材硬度水平,焊接接头伸长率和拉伸强度都优于单面焊接;双面焊接头断口呈韧性断裂,单面焊接头断口韧窝数量低于双面焊。 Through the friction stir welding process of 30 mm thick 7A52 aluminum alloy rolling plate, the influence of single-side welding and double-side welding on the microstructure and properties of welded joints was analyzed. The results show that, compared with one pass welding on one side, the welding on both sides (back two times) refine the first weld seam, eliminate the back defects of single pass, and the hardness in each area of ​​welding joints tends to be uniform. The basic Reached the base metal hardness level, the elongation and tensile strength of welded joints are better than single-sided welding; fracture toughness fracture of double-sided welded joints, single-sided welded joint fracture dimples less than double-sided welding.