放电等离子烧结技术制备(Ti-35Nb-7Zr-5Ta)-15HA复合材料微观组织的演变及生物活性

Microstructure evolution and enhanced bioactivity of(Ti-35Nb-7Zr-5Ta)-15HA biocomposites by spark plasma sintering

为了提高生物材料的生物活性并降低弹性模量,利用放电等离子烧结技术制备(Ti-35Nb-7Zr-5Ta)-15HA生物复合材料,研究不同烧结温度(950~1150℃)对复合材料相对密度、微观组织演变、力学性能及生物活性的影响。结果表明:随着温度的升高,复合材料相对密度从87.6%提高到97.5%;复合材料主要由β-Ti相、α-Ti相及陶瓷相,如Ti2O、CaZrO3、CaO、Ti5P3和Ca3(PO4)2等组成;复合材料的弹性模量为30~95 GPa、抗压强度为593~1978 MPa,而且随着烧结温度升高呈增大趋势;同时,在模拟体液中浸泡14 d后,复合材料表面能够获得类骨磷灰石,显示出良好的生物活性,但随着温度的升高,类骨磷灰石含量不断减少。因此,950℃下烧结的(Ti-35Nb-7Zr-5Ta)-15HA生物复合材料是潜在的良好的生物植入材料。

Ti-35Nb-7Zr-5Ta has suitable mechanical characteristics for orthopedic implants.However,it is not a bioactive material in the clinical application.A composite of Ti-35Nb-7Zr-5Ta and hydroxyapatite(HA)can be used to promote the growth of bone cells on the implant.Hence,we report a rapid fabrication of(Ti-35Nb-7Zr-5Ta)-15HA composites using spark plasma sintering(SPS)at different temperatures.The effects of temperature on the relative density,phase composition,microstructure,mechanical properties and biological activity of(Ti-35Nb-7Zr-5Ta)-15HA were investigated.(Ti-35Nb-7Zr-5Ta)-HA composites possessed matrix of β-Ti phase,α-Ti phase and ceramic phases(Ti2O,CaZrO3,CaO,Ti5P3 and Ca3(PO4)2).Compression test reveals that the sintered(Ti-35Nb-7Zr-5Ta)-15HA composites exhibit excellent elastic modulus(30?95 GPa)and compression strength(593?1978 MPa),ensuring a better behavior as an implant material.Furthermore,the addition of HA can improve the bioactivity of(Ti-35Nb-7Zr-5Ta)-15HA composites significantly.The low elastic modulus,high strength and good bioactivity might make this material a candidate for hard tissue implants.