EFFECT OF FRICTION STIR WELDING PARAMETERS ON DIFFERENT JOINTS AA7075-T651 AND AA6351-T6 ALUMINUM ALLOYS

Abstract

This study examined the tensile strength of two variant aluminum alloys, AA6351-T6 and AA7075-T651, by combining them in a butt joint arrangement. It was possible to use friction stir welding to weld shapes like as cylinders and triangles with tool profiles like squares, as well as rates of 40, 70, and 90 mm/min. With a maximum SV/DV ratio of 2.4 for other tool profiles, the square pin profile provided the best pulsating activity. An investigation of the nugget zone microstructure indicated that inadequate stirring of the materials caused some fractures at higher welding speeds. According to a microhardness study, the HAZ of both zones was shown to have a decreased microhardness on both sides. According to the test results, the rigidity of the nugget zone in the center was greater than the BM of AA6351-T6 and less than AA7075-T651. Process parameters were combined according to the Taguchi optimization approach, which resulted in improved tensile strength for the final product. When the process settings were optimized, the following dissimilar joints could achieve a maximum tensile strength of 183MPa: Welding Speed: -70mm/minute, Tool Rotational Speed: 1200 rpm and Tool Profile Square.