FFF of Mg-Alloys for Biomedical Application

Additive manufacturing is a very promising approach to patient-specific implants. In combination with degradability, individual tissue regeneration could be obtained. Like metal injection moulding (MIM), fused filament fabrication (FFF) of metal powders belongs to binder-based sintering technologies. However, FFF of metal powders does not require an expensive mould, but it offers individual prototyping of sophisticated shaped parts at low costs. FFF of metals is novel and processing of Mg powders is just at the start of development. In the present work, special Mg-alloy-powder-polymer blends were developed to enable manufacturing of flexible filaments and failure-free green parts. Consolidation to final metal parts took place using SF6-free powder metallurgical (PM) sintering technique. Test specimens and implant demonstrator parts were successfully produced. The specimens showed mechanical properties of up to 177 MPa UTS, 123 MPa yield strength and 2.8% elongation at fracture. Thus, the mechanical properties are equivalent to those of as-cast material. Based on these results, FFF appears to be a very promising approach to Mg implant production.