The invention relates to the technical field of flux-cored wires, and discloses a high-
nitrogen high-elongation stainless steel flux-cored wire and a preparation method thereof. According to the
welding wire, a 316L stainless steel strip is adopted as an outer
skin, the optimal components of the 316L stainless steel strip comprise 0.1%-0.2% of
nitrogen and 7%-8% of
nickel, and the 316L stainless steel strip is matched with flux core
powder of a specific formula. The flux core comprises 30%-40% of
chromium powder, 4%-12% of
molybdenum powder, 2%-6% of
metal nitride, ferrozirconium and the like, and the
nitrogen content of a
welding seam ranges from 0.20% to 0.30% through the synergistic nitrogen supply mechanism of the steel strip and the flux core. The
zirconium element is introduced to form a stable ZrN compound with nitrogen, the
copper element is added to improve the nitrogen
solid solubility, and grains are refined in combination with the
ferrotitanium alloy. And
argon-rich gas is adopted for shielded
welding, so that nitrogen escape and
oxide inclusion are effectively inhibited. The
nickel content of the obtained weld joint is 7.5-10%, the
ductility is larger than or equal to 30%, and the high strength and
plasticity are achieved through nitrogen strengthening and
microstructure regulation and control while the
nickel consumption is reduced.