Microstructure and mechanical properties in dissimilar friction stirwelding between aluminum ۱۰۵۰ and ۳۱۶L stainless steel

Friction stir welding is a solid state welding method. Now, for joining the variety ofmaterials, especially dissimilar metals, has many applications. Considering that thewelding of aluminum to steel by fusion methods is difficult due to the formation ofintermetallic compounds, therefore, by using friction stir welding, it is tried to determineand select the optimal parameters to make a joint with microstructure and properties. Thedesired mechanical properties were achieved. The purpose of this research is toinvestigate the change of rotational speed and traverse speed on the microstructure andmechanical properties of the joint in friction stir welding of aluminum ۱۰۵۰ and ۳۱۶Lstainless steel. For this purpose, the microstructure, thickness of intermetalliccompounds, hardness and tensile test on the joint were investigated. The proper selectionof welding parameters leads to the creation of a joint with suitable metallurgical andmechanical properties. In this research, two rotational speeds of ۵۶۰ and ۹۰۰ rpm andfour traverse speeds of۶۰, ۸۰, ۱۰۰ and ۱۲۵ mm/min were performed. The microstructureconsisted of four areas of the base metal, heat affected zone, thermo-mechanical affectedzone and stir zone. In all the samples, the stir zone (SZ) contained a recrystallizationmicrostructure with fine equiaxed grains. According to the Energy dispersive X-raySpectroscopy results, an IMC layer formed in the joint interface. The hardness of the stirzone in all samples was higher than the aluminum base metal. The best sample in termsof mechanical properties was obtained in the conditions of rotation speed of ۹۰۰ rpm andadvance speed of۱۲۵ mm/min. The strength was equal to ۸۴ MPa with ۷۷% efficiency

کلیدواژه ها:

Friction Stir Welding ، Dissimilar Joint ، ۳۱۶L Stainless Steel ، Aluminum ۱۰۵۰ ، Intermetallic Compounds ، Microstructure And Mechanical Properties