No abstract

Ti6Al4V (Ti64) alloy is the most used metal material for bone implants because of its good biocompatibility and adapted mechanical properties. Nevertheless, it shows low antibacterial activity, which may favor its failure. Addition of antibacterial elements such as copper should avoid this drawback. This work studies the addition of Cu into a Ti64 matrix resulting in Ti64/xCu composites. Powder mixtures of Ti64/xCu were compacted in a die and then sintered at 1100 °C. Sintering kinetics indicate that densification is achieved by pore filling due to eutectic liquid formed by the reaction of Ti and Cu. The microstructure of the sintered samples is composed mainly of α-Ti and Ti2Cu phases, but TixCuy intermetallics were also found. Microhardness is increased by the addition of Cu due to densification and the formation of harder phases such as Ti2Cu. However, the stiffness and compression strength are barely the same for all composites. The corrosion resistance is significantly improved by the addition of Cu. Finally, the material with 15 wt% of copper showed the best compromise.

This paper deals with powder processing of Ti6Al4V titanium alloy based materials with tailored porosity and composition. Ti6Al4V powder was mixed either with salt particles acting as space holder, so as to provide two-scale porosity, or with hard TiN particles that significantly modified the microstructure of the material and increased its hardness. Finally an original three-layer component was produced. Sample microstructure was observed by SEM and micro-tomography with special interest in pore size and shape, inclusion distribution and connectivity. Compression tests provided elastic modulus and yield stress as functions of density. These materials are representative of bone implants subjected to complex biological and mechanical conditions. These results thus open avenues for processing personalized implants by powder metallurgy.