Induction heating in a wire additive manufacturing approach

In additive manufacturing (AM), three-dimensional objects are built layer by layer by joining each layer to the previous one. For metal parts, there are three main methods: powder bed, powder deposition, and wire deposition. This latter makes optimal use of the material in contrast to other processes, which makes it very interesting industrially. Indeed, with powder, the ratio between powder used and powder melted is not equal to one, in opposition of the use of wire. In order to ensure the proper melting of the metal, several methods already exist, including the use of lasers or electric arc. This paper presents a novel approach of wire deposition using inductive energy for additive manufacturing applications. This approach does not make use of a storage of the molten material. Instead, the tip of a metal wire is melted by an induction heating system. Inductive energy is also used to obtain an optimal thermal gradient between the tip of the wire and the substrate or previous layer. A numerical model has been developed and validated experimentally. It shows that the induction heating system is able to melt the tip of the wire and heat the substrate to create suitable deposition.