Study on the Effects of Tetraborate Cation on the Microstructure and Properties of Micro-Arc Oxidation Coatings on TA1 Titanium Alloy

In this study, micro-arc oxidation (MAO) was applied to TA1 titanium alloy using an electrolyte primarily composed of B4O72-, resulting in the successful formation of micro-nano hierarchical rough structure. MAO treatments were conducted in tetraborate-based alkaline solutions containing different cations (Li⁺, Na⁺, K⁺) under constant current conditions. The microstructural characteristics of the oxide layers were systematically investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Furthermore, the influence of the cation type on layer thickness, surface roughness, and corrosion resistance was evaluated. The results demonstrate that the oxide layer formed in the Na₂B₄O₇ electrolyte exhibits superior performance in terms of thickness, surface roughness, adhesion strength, and corrosion resistance compared to those obtained using the other two electrolytes.