Measuring Mechanical Properties of Fillet Arc T-Welded Aluminum Alloy AA7xxx Extrusions Using Digital Image Correlation

摘要

There has been an increasing interest in fabricating automotive components from copper (Cu)-lean 7xxx-series aluminum (Al) alloys because of their relatively high strength, toughness, energy absorption, weldability, and formability. Fusion arc welding is a preferred process to join these alloys to other Al alloys during assembly. A study was undertaken to characterize the mechanical (tensile-shear) response of single-sided fillet arc T-welded joints between Cu-lean AA7xxx extrusions and AA6063 sheet made using the gas metal arc-welding (GMAW) process and ER5356 filler wire. Strain measurements were made using an ARAMIS system based on digital image correlation (DIC). An upper-bound analysis (UBA) was conducted to derive an empirical model of the upper-bound strength of the arc-welded joints. The good agreement between the predicted and experimental results shows that the empirical model can be used to evaluate the tensile-shear response of the dissimilar Al alloy arc-welded joint.