HYDROXYAPATITE COATINGS ON TI-BASED IMPLANTS

外科和牙科植入物是增长最快的领域之一 医疗保健行业的部门。 多达40种生物材料 用于医疗和牙科手术中使用的 50 种假肢装置。 拟议的研究计划旨在培养具有强烈依从性的 钛合金植入物上的生物活性羟基磷灰石 (A) 涂层。 的 计划旨在培养对依从性的基本理解 HA 的（粘合）、内应力和界面断裂抗力 钛合金涂层。 该计划有三个主要目标：1) 在钛合金上开发粘附力强的生物活性涂层，2) 阐明对涂层/钛附着力的详细了解，以及 3) 提供对机械退化的基本了解 保护性商业和实验 HA 涂层 内应力和界面断裂阻力的测量 用于 HA/Ti 涂层系统。 P2O5-MgO-CaO-SiO2-Na2-O-K2O体系中的几种玻璃 系统将准备好。 这些眼镜是根据生物活性进行改造的 玻璃最初由 Hench 开发。 涂料将被研究 润湿并准备用于界面反应研究的样品。 涂层 样本将通过 SEM、微探针和薄膜 X 射线进行分析 衍射（TF-XRD）来识别发生在的氧化还原反应 界面和眼镜，以及界面本身的分析 螺旋钻和 XPS 与平行于表面的缓慢溅射 界面。 眼镜的稳定性将在模拟体液中确定 （SBF）实验。 浸泡实验后的玻璃表面 SBF 将按顺序通过 SEM、TF-XRD、AAS、ICP 和 FTIS 进行分析 确定玻璃表面 HA 形成的程度。 内应力和热膨胀失配应力将为 通过执行原位偏转的精细方法进行分析 用于确定残余应力和应力的测量 涂层系统内的梯度。 目标将是发展 具有足够精度的方法来表征两个应力 界面和热应力并提供充分的描述 涂层分层和开裂的驱动力。 的 涂层的断裂抗力和涂层 Ti/界面将为 在室温下通过断裂力学测试和拉伸进行研究 涂层样品的测试。 压痕测试也将用于 测量裂纹扩展的阻力（即“韧性”） 界面，从而提供键的定量测量 力量。

Surgical and dental implants represent one of the fastest growing sectors in the health care industry. As many as 40 biomaterials are used for the 50 prosthetic devices used in medical and dental surgery. The proposed research program seeks to develop strongly adherent bioactive hydroxapatite (A) coatings on Titanium alloy implants. The program aims to develop a basic understanding of adherence (bonding), internal stresses and interfacial fracture resistance for HA coatings on Ti alloys. The program has three main goals: 1) to develop strongly adherent bioactive coatings on Ti alloys, 2) to elucidate a detailed understanding of the coating/Ti adherence, and 3) to provide fundamental understanding of the mechanical degradation of protective commercial and experimental HA coating layers through the measurement of internal stresses and interfacial fracture resistance for the HA/Ti coating systems. Several glasses in the system P2O5-MgO-CaO-SiO2-Na2-O-K2O system will be prepared. These glasses are adapted based on bioactive glass originally developed by Hench. Coatings will be made to study wetting and prepare specimens for interfacial reaction studies. Coated specimens will be analyzed by SEM, microprobe and thin film x-ray diffraction (TF-XRD) to identify the redox reactions that take place at the interface and with the glasses, and analysis of the interface itself by Auger and XPS with slow sputtering of surfaced parallel to the interface. Stability of the glasses will be determined in simulated body fluid (SBF) experiments. Glass surfaces after immersion experiments in SBF will be analyzed by SEM, TF-XRD, AAS, ICP and FTIS in order to determine the extent of HA formation on glass surfaces. Internal stresses and thermal expansion mismatch stresses will be analyzed by refined methods for performing in situ deflection measurements for determination of the residual stresses and stress gradients within the coating system. The objective will be to develop methods with sufficient precision to characterize both stresses at the interface and thermal stresses and to provide an adequate description of the driving forces for coating delamination and cracking. The fracture resistance of the coatings and the coating Ti/interface will be studied at room temperature by fracture mechanics testing and tensile testing of coated specimens. Indentation tests will also be used to measure the resistance to crack propagation (i.e., "toughness") of the interface, and thereby provide a quantitative measure of the bond strength.