Face Bend Property of 7N01-T4 Aluminum Alloy MIG Welded Joint by Using Different Welding Wires

Abstract

7N01-T4 aluminum alloy were welded into three layers by metal inert gas (MIG) welding, with ER5087 welding wire containing Zr and ER5356 welding wire without Zr, respectively. The microstructures and face bend properties of the ER5356 and ER5087 welded joints were investigated. The weld zone (WZ) of the ER5087 welded joint had a smaller grain size than that of the ER5356 welded joint. Two kinds of welded joints were not broken via the face-bend test. However, there were some small holes and microcracks on the surface of the ER5356 welded joint, and there were no obvious defects on the surface of the ER5087 welded joint. The face bending specimen metallography shows that the grains of the cover layer were elongated, and the grains of the bottom layer were extruded. The ER5087 welded joint had a better bending performance than the ER5356 welded joint due to the microstructure refinement of the WZ through adding Zr element in ER5087 welding wire.