Mo and Nb elements have been considered as beta-stabilizer and non-toxic elements in Ti alloy. Therefore, Ti-17 wt-% Mo-10 wt-% Nb alloy was used to reduce the Young's modulus and improve the biocompatibility in this study. In addition, spark plasma sintering was used for consolidation of Ti-17Mo-10Nb milled powders by high-energy mechanical milling during 1-8 hours. Consequently, the compression strength, Young's modulus and biocompatibility could be improved by proper milling time of Ti-17Mo-10Nb powder. To investigate the microstructure, phases and mechanical properties of Ti-17Mo-10Nb alloy, scanning electron microscope, X-ray diffraction and compression test were conducted. Also the biocompatibility and corrosion resistant of this alloy was conducted by MTT (tetrazolium-based colorimetric) assay and polarization measurement, respectively. The results showed that biocompatibility of this alloy was improved by increasing milling time and Young's modulus of Ti-17Mo-10Nb alloy decreased by using 8 hours milled powder.

The influence of yttrium addition on high-temperature performance of stress rupture property and oxidation resistance in Inconel 713C has been investigated. High-temperature stress rupture property and oxidation resistance property of Inconel 713C were dramatically improved with increasing yttrium addition content up to 0.02% yttrium, then decreased in excess of yttrium. Especially, the carbide morphology changed to discrete blocky shapes by causing improved high-temperature properties. Intermetallic compounds by excess yttrium addition made a poor stress rupture life. The high-temperature oxidation resistance of 0.02 wt-% yttrium added Inconel 713C improved more than no added yttrium Inconel 713C.

Biomaterials of titanium and its alloys are useful as implant materials in orthopaedic surgery. In this study, porous Ti-13wt% Nb-13wt% Zr biomaterials were successfully fabricated using powder metallurgy by adding 10-30 wt-% NH4HCO3 as a space holder and TiH2 as a foaming agent to mixed and milled Ti-Nb-Zr powders. The alloy powders were consolidated by spark plasma sintering process at 1123 K under 30 MPa conditions. The effect of space holder content on the pore size and distribution of the Ti-13wt% Nb-13wt% Zr (TNZ) alloys was observed by optical microscopy and scanning electron microscopy. These microstructure observations revealed that the volume fraction of the pores increased with increasing space holder content. The pore size of the TNZ alloy changed from the 100 mu m scale to the 10 mu m scale with increasing milling time and space holder content in the TNZ powders. The porous TNZ alloys exhibited good biocompatibility.