محمد ناصری النجق - Faculty of Materials Engineering, Sahand University of Technology, Tabriz, Iran.
توحید سعید - Faculty of Materials Engineering, Sahand University of Technology, Tabriz, Iran.

The purpose of this research is to investigate the change of rotational speed and traverse speed on the microstructure and mechanical properties of the joint in friction stir welding of aluminum ۱۰۵۰ and ۳۱۶L stainless steel. For this purpose, the microstructure, thickness of intermetallic compounds, hardness and tensile test on the joint were investigated. The proper selection of welding parameters leads to the creation of a joint with suitable metallurgical and mechanical properties. In this research, two rotational speeds of ۵۶۰ and ۹۰۰ rpm and four traverse speeds of ۶۰, ۸۰, ۱۰۰ and ۱۲۵ mm/min were performed. The microstructure consisted of four areas of the base metal, heat affected zone, thermo-mechanical affected zone and stir zone. In all the samples, the stir zone (SZ) contained a recrystallization microstructure with fine equiaxed grains. According to the Energy dispersive X-ray Spectroscopy results, an IMC layer formed in the joint interface. The hardness of the stir zone in all samples was higher than the aluminum base metal due to the formation of recrystallization fine equiaxed grains and the presence of steel particles. The best sample in terms of mechanical properties, mocrostructure and joint quality was obtained in the conditions of rotation speed of ۹۰۰ rpm and advance speed of ۱۲۵ mm/min. The strength was equal to ۸۴ MPa with ۷۷% efficiency.

Friction stir welding, Dissimilar joint, ۳۱۶L Stainless steel, Aluminum ۱۰۵۰, Intermetallic compounds, Microstructure and Mechanical .properties, جوشکاری همزن اصطکاکی, اتصال غیرهمجنس, فولاد زنگ نزن L۳۱۶, آلومینیم ۱۰۵۰, ترکیب بین فلزی, ریزساختار و خواص مکانیکی.