نوع مقاله : مقاله پژوهشی
نویسنده
گروه مهندسی مکانیک، واحد فسا، دانشگاه آزاد اسلامی، فسا، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسنده [English]
In this research, dissimilar metals of austenitic stainless steel 310 and 316 were welded using Pulsed Current Gas Tungsten Arc Welding (PCGTAW) method. Welding was performed under the protection of Ar and Ar-10% CO2 gases and using three filler metals ER309L, ER310 and ER316L as process variables, and the effect of different shielding gases and filler metals on the microstructure and mechanical properties of the welded samples were evaluated. The microstructure of welded joints was examined by optical microscope. Mechanical properties of joints were evaluated using tensile, microhardness and impact tests. The results obtained have shown that changing the type of filler metal causes a change in the microstructure, especially in the morphology of ferrite, and the filler metal 316 resulted in the formation of columnar skeletal ferrite in the microstructure of the welds and Coaxial skeletal ferrite was observed in the microstructure of the remaining welds as well. Also, in specimens welded with the mixed shielding gas, due to the increase in the input heat, coarse-grained ferrite phase was seen in the microstructure of the welds and the impact energy decreased. After the tensile test, the failure of all tested samples occurred in the HAZ area and the base metal, which shows the high tensile strength of the weld metal in all specimens. Finally, by comparing the obtained results, the ER309 filler metal and mixed shielding gas of Ar-10% CO2, were identified as the most suitable option for joining dissimilar austenitic stainless steel 310 to 316.
کلیدواژهها [English]
)