Additive manufacturing (AM) consists in the fabrication of parts via the gradual addition of matter, most often layer-by-layer. The most common AM processes to build metallic parts use high energy sources such as a laser, an electron beam or a plasma to solidify powder. This allows the manufacturing of complex and personalised geometries; however, the high intensity of those energy sources generates an elevated carbon footprint and results in complex and turbulent melt pool dynamics, which tend to stochastically induce defects such as porosity. A less turbulent and less energy-intensive additive manufacturing technology is currently under development at LMM. Metallic wire is molten through a nozzle in order to produce a small drop of metal bridging the nozzle and the built part, which bonds and solidifies onto the previous manufactured layer, as is now practiced on desktop machines with thermoplastic polymers.
The goal of this semester project will be first to manufacture Al-Cu wires and then to use these wires in the process currently under development in the LMM. Production of the wires is to be achieved by a combination of casting and wire drawing, potentially with intermediate steps if needed. The student will first cast the Al-Cu alloy into small ingots and will then devise the optimal combination of techniques in order to obtain a continuous and homogeneous wire out of this difficult to cast metal. The quality of the wire will be assessed using metallography and mechanical testing. Finally, time allowing, the wire will used in the AM set-up in order to manufacture a line and, with enough wire, a wall.