Effects of welding flux on welding quality during arc stud welding process

In this paper, a welding flux powder with the main composite of Fe3O4, FeO and aluminum was developed to improve the weld quality of stud welding. The orthogonal test was used to optimize the interaction influences of welding flux powder and welding process parameters. The mechanism of welding flux reducing arc blow phenomenon during arc stud welding were clarified. The results show that optimized joints with an average shear strength of 308 MPa were obtained by the welding current of 600 A, welding time of 400 ms and flux addition amount of 0.26 g. The arc migration driven by welding flux led to the uniform heating process, and then the uniform heating led to uniform weld reinforcement fillet around the stud and minimize welding defects, which was responsible for the high shear strength of the joints obtained with welding flux. The Al2O3 with low electronic work function produced by the self-propagating reaction of FeO, Fe3O4 and aluminum powder was the main reason to drive the arc migration.