Analysis on microstructure and properties of under-matching weld joint of high strength steel 10Ni5CrMoV

In order to solve the inevitable cold crack problem in 10Ni5CrMoV high strength steel thick plate welding under the condition of large constraint degree, the high-chromium-nickel austenitic stainless steel welding wire with low-match strength was developed in this paper. The microstructure and properties of the welded joint were analyzed. The results showed that the formation of the welded joint was good without crack defects. The welding metal was mainly composed of dendritic austenite and a small amount of granular precipitates. The tensile strength of the joint was 800 MPa and the sample after bending test was not fractured. The impact toughness AKV (-80 ℃) was greater than 90 J, which meets the technical requirements.