Duplex Stainless Steel S31803 Welding Technology

The duplex stainless steel is refers to the metal in the metallographic microstructure both to have the austenite and the ferrite, which occupies the approximately 50% stainless steel respectively, it has good merits in bearing the localized corrosion and the synthesis mechanical properties. With the energy, chemical and marine engineering development, worldwide demand for stainless steel is not only a rapid increase in production, but also corrosion resistance requirements has been improved, therefore the new product is developing unceasingly, following is fabrication technology keeping up. In the double-phase stainless steel equipment's process of manufacture, needs to use many welding methods to the links, whether the welding process reasonable related to the safe use of equipment later.On the basis of performance analysis of duplex stainless steel, article used S31803 as experimental object, which is used commonly in the project. Develop welding process, Carry out welding, Record welding parameters in the process of first-handly. Resolve problems emerged in the welding quality assessment. These parameters in the process of welding and the problems of welding can play a useful reference after similar products.In the welding process, making the welded joint organization as the tiny even ferrite and the austenite, and ratio of phase close 1:1,to ensure the welded joints with the same materials as the excellent performance,particularly in the better corrosion resistance.The main factors affected welding organizations are:welding material, welding heat input, cooling rate and protective gas.In the article the argon arc welding wire and the welding rod arc welding rod mainly uses Sweden Avey Sita Company's AVESTA2205,the submerged-arc welding solder uses FLUX 10.93;The hot piping enters the general control between 0.6-2.6KJ/mm, between the topmost story the temperature control in 250℃below, uses Ar+2%N2 to take the controlled atmosphere.In short, the welding of duplex stainless steel S31803,it is necessary to select the right welding materials, welding methods, groove parameters, developing an appropriate welding technology,so we can obtain the assessment indicators are qualified weld. In addition, at both welding efficiency should be an appropriate use of multi-channel welding, after this one pairs of pre-treatment together can play the role of solid solution, enables organizations, small uniform weld and weld into a austenitic slightly dominated by two-phase organization, can significantly improve the overall performance of welded joints.