Chen Yang, Dou Jinhe, Pang Zengfen, Yu Huijun, Chen Chuanzhong, Feng Jinkui
Key Laboratory of High-efficiency and Clean Mechanical Manufacture (Ministry of Education), National Demonstration Center for Experimental Mechanical Engineering Education, School of Mechanical Engineering, Shandong University Ji'nan 250061 China
Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong Engineering Research Center for Superhard Materials, School of Materials Science and Engineering, Shandong University Ji'nan 250061 Shandong China
RSC Adv. 2020 Feb 26;10(14):8244-8254. doi: 10.1039/c9ra10741j. eCollection 2020 Feb 24.
Four additives (NaWO, nano-hydroxyapatite, KTiF and NaF) were added into the NaPO + NaOH + CHO base electrolyte according to the orthogonal design of four factors three levels (L (3)). Nine different micro-arc oxidation (MAO) coatings were fabricated on Mg-2Zn-0.5Ca alloys through orthogonal experiments. The effects of four additives on the microstructure, mechanical properties, corrosion resistance and biocompatibility of MAO coatings were investigated through X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), electrochemical corrosion test and degradation test. The addition of nano-hydroxyapatite and KTiF showed self-sealing effects and contributed to the corrosion resistance of the samples significantly. The addition of 0.5 g L NaWO markedly elevated the bonding strength of the coatings with the substrate. The optimal combination of factors and levels considering both mechanical properties and corrosion resistance was: 0.5 g L NaWO, 0 g L NaF, 5 g L n-HAp, 5 g L KTiF. The growth mechanism of MAO coatings combining with the visual phenomenon was discussed as well.
根据四因素三水平（L₉(3⁴)）的正交设计，将四种添加剂（钨酸钠、纳米羟基磷灰石、氟钛酸钾和氟化钠）添加到Na₃PO₄+NaOH+CH₃OH基础电解液中。通过正交试验在Mg-2Zn-0.5Ca合金上制备了九种不同的微弧氧化（MAO）涂层。通过X射线衍射（XRD）、带能谱仪（EDS）的扫描电子显微镜（SEM）、电化学腐蚀试验和降解试验，研究了四种添加剂对MAO涂层的微观结构、力学性能、耐腐蚀性和生物相容性的影响。纳米羟基磷灰石和氟钛酸钾的添加表现出自封孔效应，并显著提高了样品的耐腐蚀性。添加0.5 g/L钨酸钠显著提高了涂层与基体的结合强度。综合考虑力学性能和耐腐蚀性的因素和水平的最佳组合为：0.5 g/L钨酸钠、0 g/L氟化钠、5 g/L纳米羟基磷灰石、5 g/L氟钛酸钾。还结合视觉现象讨论了MAO涂层的生长机理。
