In this paper,aiming at the problems of poor metal Inert gas Welding (MIG) weld forming and low joint coefficient of 7A52 medium-thickness plate , taking 7A52 aluminum alloy as the research object, semi-automatic MIG was used to conduct weld bead forming tests on ER5356 wire under different welding parameters. After the test, weld bead forming characteristics such as weld penetration, weld width, weld bead remaining-height, weld wetting angle under different welding processing parameters were measured. Optimize the optimal processing parameters. The optimized process parameters was used to weld the deposited metal and butting joint. After the welding, through the testing methods include X-ray detection, mechanical property test, microstructure observation, the performance of welding butting joint using ER5356 wire was studied. The results show that the average tensile strength for butting joint is 302.5 MPa and the joint coefficient is 0.74 respectively. The fracture position of the butting joint located in the weld zone. The bending performance of the butting joint is good, without cracks and other defects. The hardness value of the weld zone is the lowest, indicating that the weld zone is the weak zone of the welding joint, which is consistent with the fracture position of the tensile test specimen. The mechanical properties and welding properties of butting joints and deposited metals are good.
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