Fabrication of the laminated Al-Zn-Cup/Al-Zn composite using friction stir additive manufacturing

Abstract

Using laminated composites instead of traditional materials is growing in various industries due to the specific properties of such composites, including high specific strength. In this study, a laminated Al-Zn alloy composite reinforced by copper powder is fabricated using friction stir additive manufacturing. It is found that by decreasing the rotational speed from 1250 to 800 rpm, the high-purity aluminium layer in the Alclad Al-Zn alloy disappears in the interface between the two sheets, creating an integrated joint at the interface of the laminated composite. Moreover, the copper rich reinforcement increased the ultimate tensile strength of the laminated composite by 8 %. The copper reinforcing particles result in the formation of ultra-fine recrystallized grains in the stir zone, and the more uniform dispersion of particles in the stir zone results in increased uniformity and finer recrystallized grains. The high-purity aluminium layer and the hook defect in the interface have weakened the connection in the interface, resulting in debonding at the interface of the layers. Fabrication of composites at the rotational speed of 800 rpm and the traverse speed of 40 mm/min results in the maximum ultimate tensile strength and the elongation of 352.20 MPa and 17.24 %, respectively.