Experimental Effects Investigation of Ultrasonic Spot Welding on Dissimilar Al3105 and Al1050 Alloys Joining

The aluminum alloys of Al1050 with thickness of one millimeter and Al3105 with thickness of half millimeter  were joined via ultrasonic spot welding (USW). To create a suitable welding, a vibrating horn (welding tool) fit to transducer and ultrasonic generator was designed using ANSYS software. Due to mechanical and thermal cycles during USW, both diffusion and mechanical mixing facilitated the formation of welded interfaces. The alloying element, Mn, in Al3105 diffused into Al1050 during USW, and diffusion behavior varied with selection of top sheet. The fracture mechanism during lap shear testing, i.e. debonding or pullout fracture, varied based on welding power, time and pressure of jack. The optimal point for the existing welding conditions was obtained. The best welding conditions were for 750 W at 2 and 3 seconds when the horn was held on the overlap of the sheets.  Also, in the tensile test, sheet rupture was performed around the welding spot (out of welding spot).