Study On Performance And Welding Process Of Domestic Nuclear GradeⅠER2209 Welding Wire

2205 duplex stainless steel has good properties and corrosion resistance, it is widely used in nuclear power construction. While its nuclear grade welding materials is very dependent on imports, which severely restricted the development of domestic nuclear power.This paper is based on the research status of nuclear welding materials in domestic and foreign, and united Shanghai Atlantic Welding Materials Co., Ltd. to designed and developed the domestic nuclear grade I ER2209 welding wire. According to the relevant provisions of the America ASME standard to test the deposited metal’s compositions and mechanical properties of the wire; studies the compositions, microstructure and mechanical properties of the welded joint by using the developed nuclear grade ER2209 wire welding2205 duplex stainless steel, and comparative analysis the welded joints of domestic common ER2209 wire and foreign nuclear E2209T1-1 wire.At the same time optimized the welding parameters of domestic nuclear grade I ER2209 wire, studied the influences of welded joints’ microstructures, mechanical properties and components in different welding heat input.The deposited metal test results showed: The deposited metal’s composition of domestic nuclear grade I ER2209 wire was in line with ASME standards, and impurity elements was controlled strictly, S and P contents were 0.004% and 0.007%. The deposited metal has excellent mechanical properties, its tensile strength reached 766 MPa, yield strength reached 568 Mpa, elongation rate reached 31.2%, impact absorbed energy at at-40℃ temperature reached 43.87 J, ferrite content reached 47 FN, which were all meet the standards.The tensile strength of the welded joint which welded by domestic nuclear grade I ER2209 wire reached 757 Mpa, while the yield strength reached 552 Mpa, elongation rate reached 35%; At-40℃ the impact energy of the welded joint’s weld center, impact value fusion line and fusion line +2mm were 47.94 J, 37.57 J, 43.52J; which were all meet the standards.The comprehensive mechanical properties of the welded joint of the domestic nuclear grade I ER2209 welding wire are similar to that the foreign nuclear grade I welding wire,which is superior to the domestic common welding wire. The composition of domestic nuclear grade I ER2209 wire welding joint control is more strict, joint ferrite content reached 45.28 FN, are better than the domestic common welding wire and foreign nucleargrade I welding wire. The welding joint microstructure is consists of ferrite and austenite,fusion zone appeared coarse ferrite and there is no harmful phase precipitates in the joint.Welding heat input has a significant impact on the performance of the joint, the best comprehensive mechanical properties of the joint were obtained when the heat input was1.15KJ/mm by using the domestic nuclear grade I ER2209 welding wire. and the ratio of austenite and ferrite in the weld is more appropriate. Too large or too small welding heat input is not conducive to the comprehensive mechanical properties of the joint.