First demonstration of a new additive manufacturing process based on metal extrusion and solid-state bonding

In this paper, a new additive manufacturing (AM) process based on extrusion and solid-state bonding is presented. The process uses metal feedstock wire which is processed in a continuous rotary extruder in order to disperse the surface oxides of the feedstock and to provide the required bonding pressure. Simultaneously, the die outlet is scraping the contact surface to provide an oxide-free interface between the extrudate and the substrate. Optical analyses of samples from a layered structure produced from AA6082 reveal that the stringers are fully merged; however, some voids and cracks are observed between the individual stringers. Still, this initial demonstration indicates that the process, upon further development, has high potential of producing near-net-shape parts at high deposition rates.