【作者】 吴振军；

【导师】 陈宗璋； 何莉萍；

【作者基本信息】 湖南大学 ， 材料学， 2006， 博士

【摘要】 近十年来,惰性生物材料的表面生物学改性已成为生物材料的研究热点之一。由于磷酸钙盐类生物陶瓷（如羟基磷灰石HA、磷酸三钙TCP等）与人体硬组织的无机成分相近,具有天然优异的生物相容性,是最有前途的惰性生物材料的表面生物学改性涂层材料之一。但涂层成分的多样性（如HA高温下分解）或单一生物活性涂层与基底材料力学性能不匹配,常造成生物涂层活性降低、涂层容易剥落等问题。因此,采用温和的工艺条件,制备同时具有较优生物相容性和力学稳定性的新型生物涂层是一项有意义的工作。本文旨在采用新的复合制备技术,研制具有较优诱导性能、较强体外耐腐蚀能力与较高结合强度的磷酸钙盐/Al₂O₃及相关复合生物涂层材料。采用扫描电镜（SEM）、透射电镜（TEM）、原子力显微镜（AFM）、傅利叶变换红外光谱（FT-IR）、电子能谱（EDS）、X-射线衍射（XRD）和电感耦合等离子原子发射光谱（ICP/AES）对所制备复合体系的形貌结构、组成及其体外稳定性和诱导能力进行了详细的分析与研究,采用动电位强极化（Tafel极化）技术研究了所制备复合体系在模拟生理环境（林格氏溶液,Ringer′s solution）中的耐腐蚀性能,分析了处理条件对Ti基HA/Al₂O₃复合生物涂层材料结合强度的影响。主要研究工作及结论如下:（1）以磁控溅射物理气相沉积（MSPVD）Ti基Al膜为底材,采用阳极氧化-水热处理复合技术首次成功制备了磷酸钙盐/Al₂O₃复合生物涂层材料。结果表明:阳极氧化电压越高,阳极氧化Al₂O₃多孔膜的孔径越大,阳极氧化Al₂O₃膜中的Ca/P原子比越高。水热处理（212℃,8 h）后,Ti基含Ca、P元素的阳极氧化Al₂O₃膜转化为磷酸钙盐/Al₂O₃复合生物涂层材料;磷酸钙盐结晶于阳极氧化Al₂O₃膜的孔洞内并外延生长至阳极氧化Al₂O₃膜的表面,部分磷酸钙盐嵌入阳极氧化Al₂O₃的孔洞内使磷酸钙盐外层和阳极氧化Al₂O₃中间层之间形成“T”形结合界面结构。（2）采用阳极氧化-恒压电沉积两步电化学方法首次成功制备了铝基HA/Al₂O₃复合生物涂层材料。HA/Al₂O₃复合生物涂层材料在模拟体液（Simulated body fluid,SBF）中显示出良好的稳定性与较强的诱导沉积能力;HA外层的沉积电压越高,铝基HA/Al₂O₃复合体系在Ringer′s生理溶液中的耐腐蚀能力越强。（3）以MSPVD制备Ti基Al膜为底材,采用阳极氧化、恒流电沉积复合技术首次在Ti基上制备了一种新型的HA/Al₂O₃复合生物涂层材料,所制备的复合生物涂层材料的外层由微米板条状缺钙HA（Ca-deficient HA,CDHA）晶体构成。在碱性介质中水热处理后,微米板条状CDHA外层转化为由纳米针状晶体构更多还原

【Abstract】 Surface biological modification of bioinert materials has received much attention during the past decade. Due to the composition similar to human bone and the corresponding superior biocompatibility, calcium phosphate, such as hydroxyapatite （HA） and tricalcium phosphate （TCP） and so on, is one of the most promising candidates for the surface biological modification of bioinert materials. However, the compositional diversity of coating caused by high process temperature and/or the mismatch of mechanical performances between coating and substrate often lead to the decrease of biocompatibility and the delamination of coating. Therefore, it is interesting to fabricate new biocatings associated with perfect biocompatibility and good mechanical stability under mild conditions.In this dissertation, to simultaneously achieve good inductive and anti-corrosion ability and to enhance the adhesion of coating, calcium phosphate/Al₂O₃ and some related composite biocoatings, in which porous anodic Al₂O₃ acts as intermediate layer, have been developed by combining multiple methods. SEM, TEM, AFM, FT-IR, EDS, XRD and ICP/AES were employed to investigate the morphologies, compositions and in vitro inductive ability of the prepared composite systems. The research on the in vitro anti-corrosion ability of the obtained composite systems in Ringer′s solution was performed by potentiodynamic polarization （Tafel polarization）. And the effect of process parameters on the bonding strength of HA/Al₂O₃ composite biocoating on Ti substrate was also determined by tensile test. The main results and conclusions were as followings:（1） Calcium phosphate/Al₂O₃ composite biocating was successfully fabricated on Ti by a hybrid technique of magnetron sputtering physical vapor deposition （MSPVD）, anodization and hydrothermal treatment.It was found that the pores of anodic Al₂O₃ became bigger and the atomic ratio of Ca/P contained in anodic Al₂O₃ increased as high anodization voltage was applied. After hydrothermal treatment at 212℃for 8 h, anodic Al₂O₃ containing Ca and P on Ti was transformed to calcium phosphate/Al₂O₃ composite biocating. The crystallization and epitaxial growth of calcium phosphate in the pores of anodic Al₂O₃ resulted in the formation of“T”shape interface between calcium phosphate outer layer and anodic Al₂O₃ intermediate layer.更多还原