Aluminum alloy and galvanized steel CMT weld joints for lightweight automobile applications

Abstract Cold Metal Transfer (CMT) lap joint of Al6061-T6 and Galvanized steel is studied in this paper using design of experiments method. Welding parameters considered for the work includes stick out distance (10 mm −14 mm), wire-feed speed (3.5 m min −1 – 4 m min −1 ) and torch angle (10˚ to 15˚). Weld strength is optimized by using Taguchi analysis by optimizing input variables with 100% argon gas and stick out distance of 14 mm and overlap region of 13 mm. Weldments were cut in shape and size as per ASTM E8 to perform uni-axial tensile test. Further ANOVA analysis is used to understand the effect of individual parameters & their contribution on weld strength. Result depicted all three input parameter significantly effects the strength. Experiments showed that Al6061-T6 is possible to be welded with the Galvanized-steel using CMT.