Porous titanium processed by powder injection moulding of titanium hydride and space holders

Biocompatibility, bone-like mechanical properties, and good bone-to-implant anchorage are current requirements for permanent implants. Porous titanium can satisfy these requirements provided that high enough porosity, big enough pores and interconnections allowing bone ingrowth can be obtained with controlled processes. In this work, porous parts are processed from titanium hydride based feedstocks containing space holders. Two formulations have been developed: a feedstock with polyethylenglycol-based binder and NaCl space holders, and a feedstock with paraffin-based binder and PMMA space holders. Depending on sintering conditions, porosity between 30% and 60% and open porosity between 10 and 40% are obtained, with pore sizes in the range from 50 to 500 μm. The microstructure, porosity and mechanical properties of porous titanium sintered at different temperatures are characterized by scanning electron microscopy and compression tests.