Research on high speed welding of stainless steel by bypass current double-sided arc welding

Aiming at the problems of low welding efficiency and welding defects by traditional welding methods of stainless steel.The high-speed welding method of bypass current double-sided arc welding was proposed.The 2 mm thick 304 stainless steel plate was studied by using the double-sided arc welding process which is composed with MIG-TIG on the front and TIG on the back.According to welding efficiency problem, it is carried out welding efficiency improvement test verification.This thesis compares and analyzes the influence of respectively from macrostructure and microstructure of weld is analyzed.The weld tensile test can verify the reliability of the mechanical properties.The results show that when the bypass current is applied, the front bypass can effectively reduce the heat input of the base metal, improving the welding efficiency and controlling the microstructure of the weld heat affected zone well, so as to achieve the effect of grain refinement.It can reduce the weld edge bite, collapse and other defects.Highlights:(1)Double-sided arc welding with bypass current is proposed to effectively control the heat input.(2)The wire cladding efficiency of stainless steel sheet butt welding has been greatly improved, It can effectively solve the problem of lower wire filling efficiency in the welding process.(3)The microstructure and properties of the heated-affected zone are well controlled.