Study On The Performance And Welding Technology Of Grade Ⅰ ER308L Argon Welding Wire

This paper is based on the research status of nuclear stainless steel weldingconsumables in domestic and foreign, and united Shanghai Atlantic Welding Materials Co.,Ltd. to designed and developed the domestic nuclear grade I ER308L welding wire,according to the relevant provisions of the French RCC-M standard to test the depositedmetal’s compositions and mechanical properties of the wire; studied the compositions、microstructures and mechanical properties of joints’ brazed by the wire which used TIG toweld00Cr18Ni9stainless steel, and did the welded joints’ comparative analysis withnuclear grade I ER308L wires in domestic and foreign; at the same time optimized thewelding parameters of domestic nuclear grade I ER308L wire, studied the influences ofwelded joints’ microstructures, mechanical properties and components in different weldingcurrents.The deposited metal test results showed: The deposited metal’s composition ofdomestic nuclear grade I ER308L welding wire was in line with RCC-M standards, andimpurity elements was controlled strictly, S、P content was0.006%and0.02%which farbelow the RCC-M standards; ferrite content in the deposited metal was10.6%、tensilestrength Rm was667.05Mpa、yield strength Rp0.2was335.35Mpa、elongation rate was50.5%、impact energy was90.33J, which were all in line with RCC-M standards.The tensile strength of the welded joint which brazed by domestic nuclear grade IER308L welding wire was636Mpa、yield strength Rp0.2was327Mpa、elongation rate A%was50%; The impact energy of the welded joint’s weld center, impact value fusion line andfusion line+2mm were86.70J,104.50J,111.87J; The ferrite content in welded joint was9.8%, which were all in line with RCC-M standards.Under the same conditions of welding parameters, the tensile properties of the weldedjoint which brazed by domestic nuclear grade I ER308L welding wire was better thannuclear grade I ER308L wires’ in domestic and foreign; And the impact energy of thewelded joint’s weld center, impact value fusion line and fusion line+2mm were all higherthan the foreign nuclear grade I wire’s and the ordinary domestic ER308L wire’s; And theferrite content in the joint which brazed by domestic nuclear grade I ER308L welding wirewas9.8%, and the joint’s corrosion resistance and thermal cracking were the best.Welding parameters had significant effect on the joint performances, the joint’s brazedby domestic nuclear grade I ER308L welding wire with120A welding current was the best, and the ferrite content in the joint was appropriate. Too large or too small welding currentwere not conducive to joint’s mechanical properties, with the welding current increased to140A, ferrite content in the joint was beyond the standard range.