Effect of Voltage on the Microstructure and High-Temperature Oxidation Resistance of Micro-Arc Oxidation Coatings on AlTiCrVZr Refractory High-Entropy Alloy

In order to improve the high-temperature oxidation resistance of refractory high-entropy alloys (RHEAs), we used micro-arc (MAO) technology prepare ceramic coatings on AlTiCrVZr alloy, and effects voltage microstructure were studied. this paper, MAO was adjusted 360 V, 390 420 450 V. The microstructure, elements distribution, chemical composition, surface roughness studied by scanning electron microscopy (SEM), energy dispersive (EDS), X-ray photoelectron spectroscopy (XPS), white-light interferometry. matrix alloy MAO-coated samples oxidized at 800 °C for 5 h 20 study their resistance. results showed that as increased, coating gradually became smooth dense, decreased, thickness increased. substrate solute ions in electrolyte participated formation reaction, composition dominated Al2O3, TiO2, Cr2O3, V2O5, ZrO2, SiO2. Compared with prepared different voltages improved after °C, V best h. short, can prevent diffusion O into volatilization which improves RHEAs.