Research on Friction Stir Welding of Electric Control System Accessories of New Energy Vehicle Charger

In this paper, the microstructure and mechanical properties of AlSi10Mg and 5052/AlSi10Mg connectors involved in the welding package of electronic control system components of new energy vehicle chargers were studied. The results show that the grains in stir zone of the two joints are obviously refined due to dynamic recrystallization by electron backscatter diffraction technique. The grains in stir zone of AlSi10Mg are broken into particles by the precipitate phases pinning effect, showing a finer state. The grain size and precipitate phases distribution in different regions lead to different hardness in different regions of the joint. The tensile strength of the AlSi10Mg joint is 229 MPa, which is 95.4% of AlSi10Mg. The minimum hardness and the fracture position are both in the heat affected zone at the top of the joint advancing side. The tensile strength of 5052/AlSi10Mg joint is 179 MPa, reaches 90% of 5052-H32 and 74.5% of AlSi10Mg, respectively. The fracture position is at the junction of the two aluminum alloys, and the minimum hardness is located in the heat affected zone of 5052-H32.