Abstract: Stress shielding is caused by the mismatch of stiffness between bone and implant materials, which may give rise to bone resorption and loosening, thereby causing implantation failure. There is a huge gap between Young's modulus of human bone and low Young's modulus β Ti alloys. A porous structure design can achieve the target of low Young's modulus, and thus achieve the matching between human bone and implant materials. However, a suitable space holder (SH) that can be applied at high temperatures and sintering pressure has not been reported. In this study, the TiZrNbTa/Ti titanium matrix composite (TMC) with high strength and large ductility was used as scaffold materials and combined the SH technique with the spark plasma sintering (SPS) technique to obtain a porous structure. A novel space holder, i.e., MgO particles was adopted, which can withstand high-temperature sintering accompanied by a sintering pressure. The porous TiZrNbTa/Ti with 40 vol.% MgO added exhibits a maximum strength of 345.9 ± 10.4 MPa and Young's modulus of 24.72 ± 0.20 GPa, respectively. It possesses higher strength compared with human bone and matches Young's modulus of human bone, which exhibits great potential for clinical application.

Key words: TiZrNbTa/Ti titanium matrix composite, MgO space holder, Low Young's modulus, High strength