Improvement of protective oxide layers formed by high-frequency plasma electrolytic oxidation on Mg-RE alloy with LPSO-phase

Oxide layers on Mg97Y2Zn1 magnesium alloy with strengthening LPSO-phase were formed by plasma electrolytic oxidation (PEO) in bipolar mode frequency variation of forming current pulses (50 and 500 Hz) addition sodium aluminate or silicate to alkali phosphate fluoride electrolyte. Microstructure, chemical phase composition, corrosion mechanical properties the oxide investigated. With increasing for both electrolytes, an increase homogeneity structure a decrease their porosity fracturing at constant thickness recorded. The Hz even some hardness have better adhesive strength 2 orders magnitude higher short-term resistance values. PEO Mg-alloy electrolyte combination increased pulse (500 allows best-quality uniform layer high hardness, properties. use reduced 1.5 times brought down long-term order magnitude, as compared aluminate. reason significant improvement complex protective is supposed be power duration individual microarc discharges simultaneous number per unit oxidized area.