ABSTRACT

The influence of Microarc Oxidation (MAO) modes of titanium substrate in electrolytes of the original composition is investigated. Used electrolytes no contain sodium silicate but includes nickel sulphate, sodium aluminate and alkali. The morphology and composition of the obtained coatings were studied by electron microscopy. The electrochemical behaviour was studied using polarisation curves and electrochemical impedance spectroscopy (EIS). Proposed Equivalent circuits are adequately corresponded to experimental EIS data with no more 6% error. The dependence between the elements of the Equivalent circuits and the morphological characteristics depending on the processing is considered. It is shown that MAO coatings on titanium have high corrosion resistance in an aggressive sulphuric acid. The electrochemical properties of coatings undergo irreversible changes in the direction of deterioration after anodic polarisation. It has been established that nickel doping of MAO coatings on titanium does not allow them to serve as anode materials.

摘要

研究了原始成分电解液中钛基体微弧氧化（MAO）模式的影响。使用的电解液不含硅酸钠，但含有硫酸镍、铝酸钠和碱。通过电子显微镜研究了所得涂层的形貌和成分。使用极化曲线和电化学阻抗谱（EIS）研究电化学行为。所提出的等效电路与实验 EIS 数据充分对应，误差不超过 6%。考虑了等效电路的元件和取决于处理的形态特征之间的依赖性。结果表明，钛上的 MAO 涂层在腐蚀性硫酸中具有较高的耐腐蚀性。阳极极化后，涂层的电化学性能朝劣化方向发生不可逆的变化。已经确定，钛上 MAO 涂层的镍掺杂不允许它们用作阳极材料。