Fabrication and Mechanical Properties of Porous Ti/HA Composites for Bone Fixation Devices

Porous Ti (pTi)/hydroxylapatite (HA) composites were fabricated by an infiltration method in a vacuum and sintering. The Young’s modulus of the composites was evaluated before and after the immersion in Hanks’ solution. The strength of the composites was also evaluated by four-point bending test. The Young’s modulus of the compacts was governed by the porosity and was comparable to the human bone in the porosity range from 24 to 34%. The Young’s modulus of sintered pTi/HA composites was larger than that of pTi. The Young’s modulus of the sintered pTi/HA composites decreased after immersion in Hanks’ solution. The proof and bending strengths of the sintered pTi/HA composites were larger than those of pTi. Solid solution hardening of Ti by oxygen contributed the increase of the proof strength.