Fused deposition modeling - opportunities for cheap metal AM

Fused deposition modeling (FDM) of thermoplastic filaments has become widely used in the consumer market due to its low investment costs as well as the ability to additively manufacture freeform surfaces. Up to now a great variety of polymer filaments are commercially available. At the Fraunhofer Institute IFAM polymer based filaments with a high metal particle loading of up to 50 vol% are developed. An injection moulding 316L steel powder is used to fabricate PLA and PA based filaments using metal stearates as dispersing agents and backbone binder. After printing the green parts can be debinded and sintered. In this paper first results of the extrusion process of the steel metal powder filaments as well as printing trials using a highly adjustable experimental printing setup are presented. The process route offers the opportunity to reduce costs for additive manufactured parts in small lot sizes.