Effect Of Welding Method And Solution Treatment On Properties Of 2205 Steel Joint

With the development of industrial technology,common austenitic stainless steel is difficult to meet the increasingly stringent stress corrosion,pitting and crevice corrosion of the tunnel type,duplex stainless steel with excellent mechanical properties in many fields of industrial production has been widely concerned.The corrosion resistance and toughness of duplex stainless steel although is obviously better than that of austenitic stainless steel and ferritic stainless steel welded joints,but in the field of aerospace,rail transportation,the mechanical properties of welded joint of the machine,especially the corrosion resistance still needs to be further improved.The research on the weldability of duplex stainless steel not only has important practical significance,but also has important academic value.In this paper,the properties of welded joint of duplex stainless steel 2205 were studied.Firstly,the two welding methods of manual arc welding and TIG welding are compared and analyzed.The microstructure,mechanical and properties of the welded joint are compared,and the advantages and disadvantages of the two welding methods are compared.Subsequently,the solid solution heat treatment at different temperatures has been carried out for the TIG welding with better overall welding performance,in order to further improve the performance of the welded joint.After analysis and research,the following conclusions are drawn:1.Manual electric arc welding and TIG welding of two specimens of weld and heat affected zone of ferrite austenite by black columnar crystal and white matrix composition,the phase ratio(alpha/gamma)of the weld and HAZ is satisfactory,the austenite of TIG is more than the austenite of SMAW and the grain is smaller and The austenite distribution is even more uniform.2.The solid solution can reduce the ferrite content of TIG welded joint and improve the content of austenite.The higher the temperature of the solid solution,the higher the austenite content.When solid solution treatment temperature is 1050℃,weld seam and HAZ austenite content were 62.3% and 53.3% respectively,the mechanical properties of TIG welded joints meet the standard requirements.Weld tensile strength and hardness value has a little change,and plastic toughness is increased significantly.3.After solution treatment,the corrosion resistance of TIG welded joint has been further improved.The higher the solution temperature is,the better corrosion resistance of welded joints is.When the solution temperature is 1050℃,the corrosion rate of TIG welded joint is0.015g/m2· H,1/2 of that of specimen without solution treatment.