An efficient indirect arc additive manufacturing process for an aluminum alloy

To address the strong coupling between forming quality and melting wire speed inherent in wire arc additive manufacturing techniques for 5356 aluminum alloy, an indirect arc additive manufacturing process was developed. A systematic investigation was conducted for main wire feed speed to achieving stable composite indirect arcs and favorable weld bead formation under total side wire currents ranging from 120 to 280 A. Progressive enhancement and enlargement of the central conductive zone within the composite arc are observed as the total current increases. Bypass-coupled double-pulsed triple-wires gas indirect arc was proposed for additive manufacturing, which can effectively enhance deposition efficiency without compromising part quality. The 160 A specimen demonstrates optimal mechanical properties, where the yield strength, ultimate tensile strength, and elongation are 159.4 MPa, 256.6 MPa, and 21.4%, respectively.