分别采用三层四道和四层四道两种方式完成12 mm厚7N01铝合金板材的MIG焊接,研究层道分布对接头组织和力学性能的影响。试验结果表明:与三层四道焊相比,四层四道焊接接头气孔较少,焊道交界处晶界重熔不明显,抗拉强度和屈服强度稍高。 The MIG welding of 12 mm thick 7N01 aluminum alloy plate was completed by three layers of four layers and four layers of four layers respectively to study the influence of layer distribution on the microstructure and mechanical properties of the joints. The test results show that compared with the three-layer four-pass welding, the four-layer four-way welded joints have fewer holes, the grain boundary remelting at the weld bead is not obvious, and the tensile strength and yield strength are slightly higher.