Biocompatibility, mechanical properties and degradation of fe based alloys and composites processed by powder injection moulding

Metal Injection Moulding (MIM) is known as a viable process for series production of complex parts for biomedical applications. In this study, biodegradable iron based materials (Fe, Fe-0.6P, Fe-35Mn, Fe-ß-TCP) were prepared, processed by MIM and characterized towards biocompatibility, mechanical and degradation properties. Samples were sintered under different conditions to create a range of densities and microstructures. Cytotoxicity was tested according to ISO 10993-5. Using appropriate process parameters all materials proved non cytotoxic. Mechanical properties showed significant dependency on sintering conditions. The values recorded indicate potential usability of the materials for a range of orthopaedic implants. Corrosion behavior in vitro shows a strong dependency of the degradation rates on the medium used, and results of mechanical tests suggest significant degradation of mechanical properties. Despite the obvious need for further investigations, iron based a lloys and composites processed by PIM may be considered for future biodegradable implants in load bearing implant applications.