Welding is a vital process of the aircraft manufacturing

and the reliability of welding structure largely depends on the performance of welded joints. Aluminum alloy

as an important lightweight aerial material

has an important impact on the development of aviation industry. Magnetic pulse spot welding for connection of aluminum alloy thin plates was proposed to realize solid-phase welding of aluminum alloy plates. The influence of process parameters on the welding quality of aluminum alloy spot welded joints was studied by changing the welding standoff distance. Photonic Doppler velocimetry (PDV) was used to obtain the information of the flying plate during deformation processes. The mechanical properties of the joint were evaluated by quasi-static shear tensile test. The microstructure of welded joint was analyzed by optical microscope

polarizing microscope and scanning electron microscope (SEM). The results show that when the welding standoff distance increases from 0.9mm to 1.5mm

the speed of the flying plate and the welding length of the spot-welded joint both increase accordingly

which has a positive effect on the increase of welding length and the performance of spot-welded joints. After comprehensive analysis

it is concluded that 1.2mm welding standoff distance provides a suitable collision velocity for welding parts

and the mechanical performance is the best.