Influence of gas tungsten arc welding parameters on the formability of aluminum tailor welded blanks

Automobile designers are always looking for new technologies to reduce vehicle weight and manufacturing costs. An opportunity to meet these seemingly conflicting requirements is through the use of Tailor-Welded Blanks (TWBs). Welding method and its parameters have an important effect on the formability and mechanical properties of TWBs. In this study, gas tungsten arc welding (GTAW) is used to join aluminum TWBs. Aluminum TWBs consist of 6061 aluminum sheets with different thicknesses of 1mm and 2mm. Main parameters of GTAW consist of welding current, shielding gas pressure, welding speed and diameter of filler material are investigated in the present study. Design of experiment based on the Tauguchi method is used to investigate the effect of each parameter and also parameters interaction. Erichsen formability test (out-of-plane forming test) is used for formability investigation of aluminum TWBs. Forming height of Erichsen test is used as a criterion to study the effect of GTAW parameters on the quality of aluminum TWBs. The obtained results indicate that shielding gas pressure and welding speed have the greatest impact on the formability of aluminum TWBs.