Abstract
AA7075-T651, an Al-Zn-Mg-Cu alloy, is specifically used for aircraft applications due to its high strength-to-weight ratio, which improves fuel economy in lightweight construction. Cold wire pulsed gas metal arc welding (Cold Wire-P-GMAW) was used to weld AA7075-T651 joints at two travel speeds (90 and 100 cm/min) using ER5183, while the wire feed speed (WFS), voltage, and average current were selected to keep the nominal heat input approximately equal to 0.4 kJ/mm. Results showed that the cold wire feed promoted the refining of the secondary dendrite arm spacing and increased the Vickers hardness, while the high welding speed reduced porosity area, the partial melting zone and liquation cracks. Cross-sectional tensile tests showed that the joints had a joint efficiency of approximately 50%. The fractographic analysis showed that the specimen experienced a ductile fracture. The mechanical properties obtained were slightly superior to the best results in the literature; however, this was achieved with a welding speed 733% higher and without the application of thermal treatment.