Effect of niobium content on the microstructure and thermal properties of fluorapatite glass-ceramics
Effect of niobium content on the microstructure and thermal properties of fluorapatite glass-ceramics
复制标题
DOI：
10.1002/jbm.b.30295
复制
发表时间：
2005-10-01
影响因子：
3.4
通讯作者：
Walters, JD
中科院分区：
文献类型：
--
作者：
Denry, IL;Holloway, JA;Walters, JD
氧化Nb已被证明可以改善生物相容性和促进生物活性。本研究的目的是评估添加Nb氧化物对生物医用氟磷灰石微晶玻璃微观结构和热性能的影响。制备了氧化Nb含量从0增加到5wt%的四种微晶玻璃。玻璃成分在1525摄氏度熔化3小时，淬火，研磨，在1525摄氏度再次熔化3小时，炉子冷却。用膨胀法测定其热膨胀系数。用差热分析对其结晶行为进行了评价。用X射线衍射仪对晶相的性质进行了分析。用扫描电子显微镜对其微观结构进行了研究。此外，根据ASTM标准F895-84对陶瓷的细胞毒性进行了评价。X射线衍射分析结果表明，氟磷灰石是所有微晶玻璃的主要晶相。差热分析表明，根据组成的不同，氟磷灰石的结晶发生在800至934℃之间。所有含Nb微晶玻璃的热膨胀系数在7.6~9.4×10(-6)/℃之间。在975℃热处理30min后，所有含Nb微晶玻璃的显微结构均为亚显微氟磷灰石晶体(200-300 nm)，而无Nb微晶玻璃的显微结构为针状氟磷灰石晶体，长度为2微米。根据ASTM标准F895-84的测试，所有测试的微晶玻璃都没有表现出任何细胞毒性活性。(C)2005年威利期刊公司。
Niobium oxide has been shown to improve biocompatibility and promote bioactivity. The purpose of this study was to evaluate the effect of niobium oxide additions on the microstructure and thermal properties of fluorapatite glass-ceramics for biomedical applications. Four glass-ceramic compositions with increasing amounts of niobium oxide from 0 to 5 wt % were prepared. The glass compositions were melted at 1525 degrees C for 3 h, quenched, ground, melted again at 1525 degrees C for 3 h and furnace cooled. The coefficient of thermal expansion was measured by dilatometry. The crystallization behavior was evaluated by differential thermal analysis. The nature of the crystalline phases was investigated by X-ray diffraction. The microstructure was studied by SEM. In addition, the cytotoxicity of the ceramics was evaluated according to the ASTM standard F895-84. The results from X-ray diffraction analyses showed that fluorapatite was the major crystalline phase in all glass-ceramics. Differential thermal analyses revealed that fluorapatite crystallization occurred between 800 and 934 degrees C depending on the composition. The coefficient of thermal expansion varied from 7.6 to 9.4 X 10(-6)/degrees C. The microstructure after heat treatment at 975 degrees C for 30 min consisted of submicroscopic fluorapatite crystals (200-300 nm) for all niobium-containing glass-ceramics, whereas the niobium-free glass-ceramic contained needle-shaped fluorapatite crystals, 2 mu m in length. None of the glass-ceramics tested exhibited any cytotoxic activity as tested by ASTM standard F895-84. (c) 2005 Wiley Periodicals, Inc.