Microstructure and mechanical properties of flash butt welding joint of high nitrogen austenitic stainless steel

Abstract The microstructure and properties of high nitrogen stainless steel welded joints under different flash currents were studied by butt welding. results show that, the welding parameters have obvious influence on joint structure mechanical properties. is organized into symmetrical distribution, grains obtained in interface area are small, mostly pearlite ferrite. With increase current, grain coarsening overheated zone (OZ) (WZ) joint, which was mainly attributed to heat input. Martensite exists both sides weld, hardness reaches peak. tensile strength parts can reach up 97% base material, fracture form ductile fracture.