(中南大学 粉末冶金国家重点实验室，长沙 410083)
摘 要: 在无压条件下，采用添加CaF2法制备了羟基磷灰石氧化锆致密材料， 并研究了CaF2含量对HA-ZrO2材料的致密化、 微观结构和力学性能的影响。 结果显示： 在HA-ZrO2（10％～40%， 质量分数， 下同）复合材料中添加CaF2，使HA变成了分解温度高的氟部分取代羟基的磷灰石FHA， 材料的密度和力学性能（抗弯强度和断裂韧性）明显提高；加入6%（质量分数）CaF2经1 350 ℃烧结4 h后， HA-ZrO2（10％～40%）的相对密度均达到95%， 抗弯强度达到100～120 MPa， 断裂韧性提高到1.2～1.6 MPa·m1／2； 随ZrO2含量的升高， HA-ZrO2致密度有所下降； 而当CaF2含量为6%， ZrO2含量高于40%时， HA-ZrO2复合材料中形成α-Ca3(PO4)2、 HA/ZrO2固溶体或立方氧化锆， 导致复合材料的力学性能下降。
关键字: HAZrO2复合材料； 致密化； 力学性能
hydroxyapatite-zirconia composite materials
（ State Key Laboratory of Powder Metallurgy,
Central South University, Changsha 410083, China）
Abstract: Densified HA-ZrO2 composites were fabricated by adding CaF2 under pressureless condition. The effects of CaF2 content on the densification, phase compositions, microstructures and mechanical properties of HA-ZrO2 composites were investigated. The results show that the reaction between CaF2 and HA leads to the formation of fluorine partially substituted hydroxyapatite FHA with higher thermal stability, which enhances the densification, microstructures and mechanical properties of HA-ZrO2 composites. When the HA(10%-40%, mass fraction)-ZrO2 composites adding 6% CaF2 were sintered at 1 350 ℃ for 4 h, their theoretical densities can reach more than 95%. Fractural strength reaches 100-200 MPa and fracture toughness can enhance 1.2-1.6 MPa·m1／2. The effects of zirconia on phase compositions and mechanical properties were also studied. The densities of HA-ZrO2 composites decrease with increasing ZrO2 contents. When the mass fraction of CaF2 is above 6% and that of ZrO2 is above 40%, formations of CaZrO3, αCa3(PO4)2, HA/ZrO2 solid solution, and c-ZrO2 lead to the poorer mechanical property of HA-ZrO2 composites.
Key words: HA-ZrO2 composites; densification; mechanical properties
