(华中科技大学 材料成形与模具技术国家重点实验室，武汉 430074)
摘 要: 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。
关键字: 生物复合材料；钛；放电等离子烧结；羟基磷灰石；生物体外实验
（State Key Laboratory of Material Processing and Die and Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, China）
Abstract: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.
Key words: biomaterials; titanium; spark plasma sintering; hydroxyapatite; in vitro bioactivity
