纯Ti表面微弧氧化-碱热处理仿生陶瓷膜的制备及耐蚀性

采用微弧氧化-碱热处理在纯Ti表面制备了含有羟基磷灰石(HA)的仿生陶瓷膜。利用SEM,XRD和电化学工作站等手段研究了膜层的形貌、物相及其耐蚀性。结果表明:在乙酸钙-磷酸二氢钙电解液体系中微弧氧化(MAO),纯Ti表面形成一层含Ca和P的TiO2多孔陶瓷膜。经水热处理后,膜层表面的孔洞变小、致密性增加,膜层中还出现了鳞状、层片状以及针棒状的HA。在Hank's模拟体液中,MAO膜和微弧氧化-碱热处理(MAOAH)膜均表现出较好的耐蚀性。MAO膜经模拟体液腐蚀后,形成了缺钙型HA(Ca8.86(PO4)6(H2O2)2)和CaTiO3;而模拟体液中的阴离子与MAOAH膜层的氧化物作用使膜层孔洞直径和深度增加。

Preparation and Corrosion Resistance of Bionic Coatingson Pure Titanium by Microarc Oxidation and Alkali-heat Treatment

Bionic coatings composed of hydroxyapatite (HA) were prepared on the surface of microarc oxidized pure titanium. Then their morphology, phase composition and corrosion resistance were characterized by SEM, XRD electrochemical workstation respectively. The results show that a porous ceramic TiO₂ coating containing Ca and P formed on pure titanium after microarc oxidation (MAO) process in calcium acetate-calcium biphosphate electrolyte. After a post alkali-heat (MAOAH) treatment, the holes in the treated coating became smaller and the coating became denser. Moreover, scale-like, lamellar- and needle-like HA appeared in the coating. The immersion test revealed an excellent corrosion resistance to the Hank's simulated body fluid (SBF) for both MAO and MAOAH coating. After corrosion test in SBF, a calcium deficient type HA(Ca_8.86(PO₄)₆(H₂O₂)₂) and CaTiO₃ were formed in MAO coating. However, anions in SBF reacted with oxides in MAOAH coating resulting in the increase of the diameter and depth of holes of the coating.