磷酸钙陶瓷的热稳定性和显微结构  

Thermal Stability and Microstructure of Calcium Phosphate Ceramics

作　　者：蔡舒[1] 王彦伟[1] 李金有[1] 李鸿祥[1] 姚康德[2] 

机构地区：[1]天津大学材料科学与工程学院先进陶瓷与加工技术教育部重点实验室,天津300072 [2]天津大学高分子材料研究所,天津300072

出　　处：《天津大学学报（自然科学与工程技术版）》2004年第4期345-348,共4页Journal of Tianjin University：Science and Technology

基　　金：天津市重大基金资助项目(003805011).

摘　　要：用沉淀法和机械 化学法合成不同Ca与P摩尔比的羟基磷灰石,考察Ca与P摩尔比对合成羟基磷灰石热稳定性和烧结体显微结构的影响.分别采用X射线衍射、红外光谱和扫描电镜分析合成粉体及烧结体的相组成和显微结构.结果表明:Ca与P摩尔比略大于1.67的HA在烧结过程中有少量CaO形成,可有效抑制HA的分解,提高其高温稳定性;CaO晶粒可以钉扎晶界,抑制晶粒长大,但阻碍烧结.随Ca与P摩尔比减小,烧结体中晶粒尺寸增大.Ca与P摩尔比小于1.60的HA粉体,在1100℃下完全分解为β TCP相,烧结终止,继续升高温度,因β TCP相向α TCP转变伴随体积膨胀,导致裂纹产生.含碳酸根的HA的高温稳定性较差,烧结体中存在较多气孔.Synthesized hydroxyapatite(HA) powders with different calcium-to-phosphorus (Ca/P) molar ratios were prepared by precipitate and mechano-chemical methods. The effects of the initial Ca/P ratio on the phase evolution during sintering and the resultant microstructure were investigated by X-ray diffraction(XRD), Fourier transform infrared (FTIR) and scanning electron microscopic(SEM )methods. CaO formed by the decomposition of Ca(OH)_2 during sintering could effectively improve the thermal stability of HA with Ca/P ratio larger than 1.67. Meanwhile, CaO would be acted as the pinned particles to inhibit grain growth of HA, and also hinder the density sintering. The grain size of the sintered bodies increased with the decrease of the ratio of Ca/P. HA powder with a Ca/P ratio less than 1.60 was completely decomposed to β-calcium phosphate (β-TCP) at 1 100 ℃, which resulted in the end of sintering. Further increase of temperature, cracks formed by the volume expansion which was attributed to the transformation of β-TCP to α-TCP were observed. Carbonate substituted HA appeared low thermal stability and contained pores caused by the thermal decomposition.

关 键 词：磷酸钙陶瓷 热稳定性 显微结构 沉淀法 机械-化学法 摩尔比 生物材料 

分 类 号：R318.08[医药卫生—生物医学工程] TQ174.13[医药卫生—基础医学]