A novel technique to produce metallic microdrops for additive manufacturing

In additive manufacturing (AM), three-dimen sional objects are built layer by layer by joining each layer to the previous one. Those layers can be formed from the direct deposition of metallic drops resulting from the breakage of a micrometer jet. The jet is produced by ejecting through a nozzle/orifice a metal melted in a crucible. In this paper, we propose a novel technique to produce a continuous droplet stream of a low-melting-point alloy for additive manufacturing. Our technique does not make use of a crucible. Instead, the tip of a metal wire is melted by an induction heating system as it is introduced in the nozzle. If the values of the control parameters are chosen appropriately, a quasi-steady jetting regime is established. This method is much more energetically efficient than its counterparts because it consumes just the energy necessary to melt the demanded material at any times.