Microstructure and Properties of Welded Joint of 1Cr17Mn6Ni5N Stainless Steel by Plasma Arc Welding During Making Nodes

During making nodes,after stainless steel was welded by plasma arc welding,the microstructure of weld seam and heat-affected tone was observed by scanning electron microscope(SEM),and the microhardness of the weld seam was tested by micro-sclerometer.The results indicate that uniform smooth weld seam without cracks can be got by plasma welding;the microstructure of weld seam mainly includes austenite and δ-ferrite which distribute along columnar crystals,there are e-martensite inside austenitic crystals;the carbides precipitate in the heat-affected zone and there is e-martensite transition inside crystals,a few bicrystals appear in some crystals near the base metal of the fusion line and the heat-affected zone;the microhardness of the base metal,the fusion zone,and weld metal zone is 190,210,292 HV0.2,respectively.