ELECTROPHORETIC NANO-HYDROXYAPATITE COATING FOR ADHESION

粘附性差是与可植入羟基磷灰石涂层的长期生存能力相关的唯一最严重的问题。 提出了一种新颖的室温电泳工艺来制备纳米结构羟基磷灰石（“n”-HAP）涂层，消除了与非晶相形成和分层相关的问题。 到目前为止，只有微米级的羟基磷灰石材料已经使用电泳沉积。n-HAP涂层将表现出增加的韧性、结合强度和高结晶度。粘结的性质是冶金的，与热喷涂涂层中获得的机械粘结相比，粘结强度显著提高。电泳还能够实现多组分共沉积。该程序包括（1）合成n-HAP颗粒，（2）沉积n-HAP涂层，和（3）涂层评价。虽然n-HAP预期在粘结强度上产生几倍的增加，但是磷酸钙骨水泥（CPC）添加剂将与n-HAP共沉积以进一步增加粘结强度。在沉积过程中，将在n-HAP和钛基材之间引入致密的分级TiO 2粘合涂层（几微米厚），以便体液没有机会侵蚀和降解钛。Eschermat正在与劳伦斯伯克利国家实验室的Antoni Tomsia博士合作评估纳米结构涂层。拟议的商业应用：潜在的商业应用包括用于人类和动物的髋关节、膝关节和其他假体的先进涂层植入物。 仅在美国，每年使用HAP涂层植入物的髋关节和膝关节手术数量估计已经产生了30亿美元的年收入。随着人口年龄的增长，在不久的将来，对植入物的估计需求将显着上升。 一个类似的欧洲市场将使潜在收入翻一番。

Poor adhesion is the single most severe problem related to the long term viability of implantable hydroxyapatite coatings. An innovative room temperature electrophoretic process is proposed to fabricate nanostructured hydroxyapatite ("n"-HAP) coatings, eliminating problems related to amorphous phase formation and delamination. To date, only micron-sized hydroxyapatite materials have been deposited using electrophoresis. The n-HAP coating will exhibit increased toughness, bond strength, and a high degree of crystallinity. The nature of the bond is metallurgical, resulting in dramatically improved bond strength when compared to mechanical bonds obtained in thermal spray coatings. Electrophoresis also enables multicomponent codeposition. This program consists of (1) synthesizing n-HAP particles, (2) depositing the n-HAP coating, and (3) coating evaluation. while the n-HAP is expected to yield a several4old increase in bond strength, a calcium phosphate cement (CPC) additive will be cc-deposited with the n-HAP to further increase bond strength. A dense graded TiO2 bond coat will be introduced (a few microns thick) between the n-HAP and the titanium substrate in the deposition process, so that body fluids will have no opportunity to attack and degrade the titanium. Inframat is collaborating with Dr. Antoni Tomsia of the Lawrence Berkeley National Lab to evaluate the nanostructured coatings. PROPOSED COMMERCIAL APPLICATIONS: Potential commercial applications include advanced coated implants for hips, knees, and other prostheses in humans and animals. In the US alone,the annual number of hip and knee operations using HAP coated implants is estimated to already produce an annual revenue of $3 billion. With the increasing age of the larger population, the estimated demand for implants will rise significantly in the near future. A comparable European market doubles the potential revenue.