Effect of Powder Interlayer on Copper Alloy Lap Joint by Laser Welding

In this paper, the lap joint of H62 copper alloy was carried out by pulsed laser welding. The effects of different powder interlayers on the microstructure, shear properties and corrosion properties of H62 copper alloy lap joints were studied. The results show that the welding joints with proper powder interlayer have achieved good welding forming. There are no defects such as pore and crack in the welding joints. The welding joints are fully penetrated with different powder interlayers except Ni powder interlayer. The grain size of weld is smaller than that of base metal. The maximum polar density of base metal is 6.46 in (001) [0-10] cubic texture, and there are two weaker (112) [111] Cu textures and (111) [1-21] textures. The maximum polar density of the weld is 5.39. The maximum position deflects, and (001) [0-10] cubic texture disappears. The weld is confused compared with the base metal, and the grain distribution is basically of random orientation. The addition of Zn powder reduces the welding stress. The shear strength of welding joints with Zn powder interlayer is the best, 82.27 MPa, which is 18% higher than that of welding joints without powder. The corrosion resistance of welding joints with different powder interlayers is as follows: no addition > Ni Powder > Zn Powder > Sn powder.