等离子喷涂羟基磷灰石（HA）涂层由于其沉积效率高、成本低等特点，是当前制备骨科植入物HA涂层最主要的方法之一。其缺点是高温易使HA分解，涂层中结晶相含量低，普通热处理后的HA结晶度也仅为40~50%。由此首先需要解决问题是改善传统喷涂用HA粉体的性状，提高等离子喷涂的送粉效率，其次是改进晶化处理工艺，从而达到提高HA涂层的结晶相含量的目的。本文在HA粉料的制备上，运用喷雾干燥造粒手段制得HA前驱体颗粒，再经过900℃×2h的煅烧，得到了10~60μm外形为球型且具有良好流动性的HA粉体。通过XRD和FTIR分析，粉体为纯净的HA晶体且结晶度非常好。在涂层的后处理方面，本研究设计了特殊的晶化处理装置，能在高温加热过程中保持炉内充足的水蒸汽氛围，既可以使非晶态HA恢复为结晶相HA，同时可以使HA热分解产物重新转化为HA相。经过750℃×2h的联合晶化处理，等离子喷涂涂层HA的结晶度可提升到80~90%。本文选取了人工髋关节作为应用对象，通过对80例人体髋关节部位进行CT扫描，运用Mimics软件进行三维重建，获得了髋关节部位关键尺寸的研究数据。通过国内外髋关节股骨研究数据与本研究数据比对发现，本研究数据与国内其他研究数据无明显差异。依据本研究数据设计、加工的新型E系列的人工髋关节股骨柄在涂层性能、力学性能、金相观察和疲劳性能等检测中均达到了相关国家标准要求。研究表明，本文研究制备的HA粉体、等离子喷涂及其晶化处理工艺能在实际生物工程应用中得以实现，并取得了较为理想的应用效果。
Plasma sprayed hydroxyapatite (HA) coating, because of high deposition efficiency and low cost, has become one of the main methods to prepare of HA coating of orthopedic implants at present. Its defect is high temperature easy to decompose HA, leading to low crystalline phase content in the coating. After processing the crystallinity of the coating is 40~50% in general. The first problem in this study is to improve the characteristics of traditional HA powder, raise the powder feeding efficiency of the plasma spraying, followed by improving the crystallization treatment process, increasing the crystallinity of plasma sprayed HA coating.In this paper, on the preparation of HA powder, using spray drying granulation method to successfully prepare of HA precursor with 10~60μm particle size, good fluidity and spherical shape. After calcination at 900℃ for 2 hours, through XRD and FT-IR observation, the powder is pure HA crystal and its crystallization degree is very well. In terms of coating of post-processing, crystallization processing device given in this paper can keep the water vapor sufficient during heating process, therefore it not only can make the amorphous crystalline phase hydroxyapatite turn back hydroxyapatite but also can make decomposition products retransform into hydroxyapatite phase. After the crystallization treatment at 750℃ for 2h, the crystallinity of plasma sprayed HA coating can be improved to 80~90%.In this paper, we select the artificial hip joint as application object. Through collection of hip joints skeleton data of the eighty human bodies, three dimensional reconstruction of hip bone CT scan data was done using three dimensional reconstruction software (Mimics), and the key sizes of the hip joints were measured. By comparing the femur parameters, no obvious difference was found between our study data and other domestic research data. Basis on the research data, model D series of the artificial femoral hip stem had been designed and the implementation of small batch trial had been processed. By testing the product test pieces with HA coating, the results show that the properties of the plasma sprayed coating, including mechanical properties, microstructure and fatigue properties, meet the relevant national standards. The research shows that the methods of preparation of HA powders, the techniques of plasma spraying and HA coatings crystallization process in this paper can be realized in the practical application of biological engineering, and the result of application in the implant products is also ideal.
