Experimental Analysis of the mechanical properties of Aluminum Tailor Welded Blanks

Nowadays the of the reduction of CO2 emissions and the decrease in energy consumption are the aims for different industries around the world. In order to satisfy increasingly restrictive regulations, the automobile industry is constantly looking for innovative techniques to produce lighter automobiles, more efficient and less polluting. One of the latest technologies designed, and still developing, is that of Tailor Welded Blanks. TWBs are combination of multiple metal sheets with various thicknesses and/or strengths welded together using high speed weld along their edges. Over the years, the advantages of using aluminium in this technology have been discovered, thanks to its low density, high corrosion resistance, and good weldability. However, its use is limited by low formability when complex geometries come into play. This study will investigate the mechanical and microstructural properties of EN AW5754 and EN AW6016 aluminium tailor blanks obtained from a Nd:YAG laser welding process, having a variable thickness. The research is carried out in collaboration with the company CO. ST. AT. s.r.l. of Piobesi Torinese (TO), interested in the to the improvement of this process. In particular, the influence of welding parameters on tensile strength and joint formability will be studied, analyzing a L9 Taguchi model. Furthermore, through the use of the software LS-DYNA, a finite element model will be developed in order to verify if it is possible to properly simulate the tensile test and the Erichsen Cupping test.