Effect of Thickness Ratio on Weld Line Displacement in Deep Drawing of Aluminium Steel Tailor Welded Blanks

A Tailor-Welded Blank (TWB) is obtained by welding together sheets of same or different metals of different thicknesses to produce a single blank prior to subjecting it to a forming process. Some of the notable benefits of TWBs include decreased part weight, reduced manufacturing costs, increased environmental friendliness, and improved dimensional consistency. Designers nevertheless need to overcome the difficulty faced in the forming of TWBs due to material property changes in the two parent metal sheets, in the weld and heat affected zone of the weld. The purpose of the present work is to study the effect of changing thickness ratio on formability characteristics of TWBs made of aluminium and two different steels. Aluminium (AA6016-T4) blank sheet was combined with two high strength steels (HSLA-340 and DP600) with three thickness ratios(Steel/Al) of 1.0, 1.25 and 1.5 to form 6 different combinations. Rule of mixtures method is used for measuring the properties of laser weld metal in tailor welded blanks. The simulation results indicate that the weld line displacement tends to increase with the increase in the thickness ratio.