State of the art

Additive manufacturing (AM) is a free-form manufacturing technique which takes three-dimensional computer aided design (3D-CAD) model as input, adding raw material gradually, usually in a computer-controlled layer-wise manner, to build the part by consolidating the raw material applying an energy source. Additive manufacturing processes are in place for a number of decades; however, it is only possible since a number of years that metallic parts with relative densities higher than 99% can be manufactured, posing the opportunity to shift the potential of the technique from prototyping to serial production. This chapter gives a brief overview of the existing additive manufacturing processes regarding source of energy, type of raw material, processing capabilities and issues.