Microstructure and Properties of ZGMn13Mo/A514 Dissimilar Steel Multi-pass Welding

The connection of ZGMn13Mo/A514 dissimilar steel is commonly used in mining equipment. In this study, the ER309L stainless steel welding wire was used to conduct multi-pass gas metal arc welding of 25-mm-thick ZGMn13Mo/A514 dissimilar steel. The microstructure evolution of the processed samples was studied, and the tensile properties and microhardness were tested. The results showed that the weak links in the welded joint occur at the fusion boundary of ZGMn13Mo high manganese steel, and the large residual stress leads to the generation of hot cracks. Due to the secondary heating effect of the previous weld pass on the subsequent weld pass, the weld root and middle are strengthened, so the strength and hardness are improved, and the fracture occurs at the base material. This welding process has achieved good connection of ZGMn13Mo/A514 dissimilar steel.