To improve the bioactivity of Ti?Nb?Zr alloy,Ti?35Nb?7Zr?xHA(hydroxyapatite,x=5,10,15and20,mass fraction,%)composites were fabricated by spark plasma sintering.The effects of the HA content on microstructure,mechanical and corrosionproperties of the composites were investigated utilizing X-ray diffraction(XRD),scanning electron microscope(SEM),mechanicaltests and electrochemical tests.Results show that all sintered composites are mainly composed ofβ-Ti matrix,α-Ti andmetal?ceramic phases(CaO,CaTiO3,CaZrO3,TixPy,etc).Besides,some residual hydroxyapatites emerge in the composites(15%and20%HA).The compressive strengths of the composites are over1400MPa and the elastic moduli of composites((5%?15%)HA)present appropriate values(46?52GPa)close to that of human bones.The composite with15%HA exhibits low corrosion currentdensity and passive current density in Hank's solution by electrochemical test,indicating good corrosion properties.Therefore,Ti?35Nb?7Zr?15HA composite might be an alternative material for orthopedic implant applications.
Zheng-yuan HELei ZHANGWen-rui SHANYu-qin ZHANGRong ZHOUYe-hua JIANGJun TAN
