【作者】 倪嘉桦；

【导师】 石玉龙；

【作者基本信息】 青岛科技大学 ， 材料物理与化学， 2007， 硕士

【摘要】 本论文运用微弧氧化(MAO)技术，采用自制的微弧氧化简易装置于含磷酸二氢钠和乙酸钙的电解液中在商业纯钛表面制备含羟基磷灰石的氧化钛生物活性陶瓷膜层。对试验制得的膜层运用扫描电镜(SEM)、X射线能谱仪(EDX)和X射线衍射仪(XRD)等分析手段进行检测，检测结果表明：该膜层是一种多孔状、与基体结合牢固、具有陶瓷特性的复合膜层；膜层中含Ti、O、Ca、P四种元素；膜层中的物相除羟基磷灰石外还有金红石、锐钛矿。本试验通过微弧氧化技术在钛基表面直接生成了羟基磷灰石(HA)，比目前较多采用的复合法在钛基表面制备羟基磷灰石工艺简单。本论文研究了各工艺参数如电解液浓度、氧化电压等对膜层结构特征的影响，在大量试验结果的基础上，本论文给出了在目前实验条件下的最佳工艺参数：电流密度为10～20A／dm~2、电压为450～500V，氧化时间为20～30min，电解液温度为20～70℃时可得到形貌、膜厚最佳以及膜层中的磷灰石结晶度较好的膜层。并根据试验结果，结合微弧氧化的特点对膜层的生成机理进行了初步的探讨，认为电泳理论可以解释电解液中含钙、磷粒子向阳极运动的原因，扩散是钙、磷元素进入膜层的主要机制。此外，本论文在前面试验的基础上，对向含羟基磷灰石的膜层中添加一些微量元素如硅、银等元素这一想法进行了尝试。生物相容性是生物医学材料的重要评价指标之一。本论文采用体外细胞毒性试验和细胞培养试验对微弧氧化膜层进行了生物相容性的初步评价。试验结果表明，该材料的细胞毒性为0或1级，初步检验合格，能满足临床应用材料的生物相容性要求；钛表面微弧氧化改性的氧化膜有利于细胞的附着，能增强BMSCs细胞的成骨能力更多还原

【Abstract】 In the paper, the bioceramic composite coatings of hydroxyapatite （HA） andtitanium dioxide （TiO₂） on titanium substrates were formed by micro-arc oxidation（MAO） in electrolyte containing sodium phosphate monobasic dihydrate（NaH₂PO₄.2H₂O）, calcium acetate monohydrate （CH₃COO）₂Ca.H₂O) with the facilityof microarc oxidation made by ourselves. Scanning electron microscopy （SEM） withEnergy dispersive X-ray spectrometer （EDX） and X-ray diffraction （XRD） wereemployed to characterize the microstructure, elemental composition and phasecomponents of the coatings. The surface of the ceramic layer was a porous structureand the adhesion of the coatings was favorable. The oxidized coatings contained Caand P as well as Ti and O. The porous coatings were made up of hydroxyapatite, rutileand anatase. The hydroxyapatite-containing coatings on titanium substrate directlywere prepared by MAO and the process was simpler than other treatments that wereapplied presently to the preparation of hydroxyapatite-containing titania coating ontitanium or titanium alloy.The processing parameters such as the concentration of electrolyte and thevoltage which affected the coating were studied. After lots of experiments, theoptimized parameters under optimal processing condition were worked out in thepaper: the current density was about 10～20A/dm², the voltage was 450～500V, theoxidation time was 20～30min and the temperature of electrolyte was 20～70℃.Based on the results of experiment and the characteristics of micro-arc oxidation, themechanism of coating forming was discussed. The electrophoresis can explain themovement of Ca and P particle in electrolyte towards the anode. The diffusion of Caand P particle urge the Ca and P element to enter the coating. Moreover, a novel thought that microelement such as silicon and silver were separately added to thecomposite coating of HA and TiO2 by MAO was practiced in this paper.Biocompatibility is one of important evaluation of biomaterial. In the paper,cytotoxicity experiment and cellular cultivation experiment were made to evaluate thebiocompatibility of the coatings. The results showed that the level of toxicity of thecoatings was 0 or 1 and the coatings was eligible in clinic application, and that thecoating modified by MAO was in favor of the attachment of BMSCs cell更多还原