钛合金表面微弧氧化制备羟基磷灰石相陶瓷层

Formation of Hydroxyapatite Coatings on Titanium Using Plasma Micro- arc Oxidation

本论文应用微弧氧化技术，在钛合金表面生成了含有羟基磷灰石的TiO2陶瓷膜层。所用微弧氧化电解液主要由乙酸钙（（CH3COO）2Ca·H2O）和磷酸二氢钠（NaH2PO4·2H2O）配置而成，电源为双脉冲电源。能谱（EDX）分析表明，所得微弧氧化膜层主要含有Ti、O、Ca、P四种元素，其Ca／P原子比随电解液中提供钙、磷元素的乙酸钙和磷酸二氢钠的摩尔比而变，当电解液中乙酸钙和磷酸二氢钠的摩尔比由1增加到2时，膜层中Ca／P原子则由1．02增至2．08。通过X-射线衍射（XRD）分析，结果显示该氧化膜主要由金红石、锐钛矿及羟基磷灰石组成，为一种生物陶瓷。利用扫描电镜（SEM）对所得膜层的表面和断面形貌进行了分析，发现膜层表面分布有许多小孔。膜层与基体结合良好。

Hydroxyapatite coatings were formed on the surface of titanium alloy substrates using plasma micro - arc oxidation. The electrolytic solution of the plasma micro- arc oxidation contained calcium acetate （（CH3COO） 2Ca·H2O） and sodium dihydrogen phosphate （NaH2PO4 · 2H2O）. From the energy dispersive X -ray spectrometer （EDX） analysis, it showed that the coatings mainly contained four elements such as Ti, O, Ca and P, whose content depended on the concentrations and ratio of （CH3COO）2Ca · H2O and NaH2PO4 · 2H2O in the electrolytic solution. Ca/P element ratio in the coatings ranged from 1.02 to 2.08 when （CH3COO）2Ca · H2O/ NaH2PO4 · 2H2O mol -ratio varied from 1 to 2 in the electrolytic solution. In the same time. X -ray diffraction （XRD） was used to analyze the phase and structure of these plasma micro -arc oxidation -treated coatings. The analyse indicated that the coatings were mainly composed of anatase, rutile, and hydroxyapatite （HA） which is a biomaterial. The surface and cross - sectional morphology of the coatings were observed using scanning electron microscopy, it was found that the oxide coatings exhibited a porous microstructure with spherical pores, and there was a good combine between coating and substrate.