The attractive mechanical properties of 7075 alloy, such as its high strength-to-weight ratio and fracture toughness, have received special attention in the automotive and aerospace industries. However, welding as a fabrication process has a detrimental effect on this alloy’s properties which affects its mechanical performance. In this work, to compensate for the loss in mechanical properties caused by welding, proper heat treatment operations are adopted. To this end, 1.5 mm AA7075 sheets were first preheated and butt welded using the gas tungsten arc welding process. The welded sample was solution heat treated, quenched, and then artificially aged. Microhardness tests showed an increase of hardness in all zones of the aged specimen compared to those of the original welded blank before heat treatment. A maximum microhardness value of 180 HV was recorded in the heat-affected zone of the aged specimen. In addition, elongation at break, and strength (yield, tensile, and fracture) of the original welded blank increased by about 50% after the artificial aging operation. Manuscript profile

Friction Stir Welding has significantly transformed the metal joining industry, and an innovative variation known as stationary shoulder FSW has emerged. This study aimed to compare various aspects, including force, temperature, and strain, between conventional friction stir welding (CFSW) and stationary shoulder friction stir welding (SSFSW). To accomplish this, the finite element method was employed, utilizing the lagrangian technique to model the welding process. The findings revealed that in SSFSW, the highest temperature was observed in the vicinity of the rotating pin. This was attributed to the absence of a rotating shoulder in SSFSW, which played a major role in heat generation during welding. Moreover, the longitudinal forces on the tool in SSFSW were significantly higher compared to CFSW, approximately ten times greater. In the CFSW process, the affected area showing strain usually forms a basin-shaped pattern. However, in the SSFSW process, the strain distribution is confined within the range of the tool pin. Manuscript profile