Research on Welding Characteristics of Duplex Stainless Steel in Desulfurization Washing Towers
This paper focuses on the welding process of super duplex stainless steel for desulfurization washing towers.Through experimental research on the effects of welding heat input and welding rate on the macroscopic and microscopic structure,mechanical properties,and corrosion resistance of the weld metal,the optimal alloy material is selected.Results have shown that when using tungsten inert gas welding,ensuring a heat input within the range of 0.3～1.5 kJ/mm,controlling the interlayer temperature within 150 ℃,solid TIG welding wire 25.10.4 L and welding rod 25.10.4 LR,using a mixed gas composed of 98％argon particle density and 2％nitro-gen particle density,the apparent condition of the welded joint is excellent without obvious defects.The micro-structure of the weld indicates that the base metal is in a rolled form,while austenite is regularly distributed on the ferrite substrate in the form of stripes.The hardness of the weld seam is approximately 300,especially the hard-ness of the heat affected zone(HAZ)can reach up to 330.The impact toughness of the weld seam is between 110-140 J/cm2.There is no pitting on the surface,and its corrosion rate is less than 10mdd.In a 40℃ environment containing chloride and sulfate ions,welded joints still exhibit certain resistance to pitting corrosion.
万方数据
维普
