Gas shield welding process for marine corrosion-resistant steel with yield strength of 420 MPa

The invention discloses a gas shielded welding process for marine corrosion-resistant steel with yield strength of 420 MPa, which adopts an easy-to-operate gas shielded welding process to weld the marine corrosion-resistant steel with yield strength of 420 MPa, and ensures that the low-temperature impact energy KV2 of a welded joint at-40 DEG C is greater than or equal to 47J, the tensile strength of the welded joint is greater than or equal to 540 MPa, the welded joint has excellent corrosion resistance, and the service life of the welded joint is prolonged. The atmospheric corrosion resistance index V of a weld joint is larger than or equal to 1.2, an industrial atmospheric cycle dipping/drying cycle corrosion test is simulated, a welded joint has no obvious step, and the welded joint formed by the welding technology obtains good comprehensive use performance and is suitable for welding of marine corrosion resistant steel with the thickness of 16-60 mm and the yield strength of 420 MPa. 本发明公开了一种屈服强度420MPa级耐