Mechanical and anticorrosive properties of oxide layers formed by PEO on wrought 1560 Al-Mg alloy: The effect of electric current parameters

Abstract

The parameters of electric current play a decisive role in ensuring the quality of oxide layers formed on non- ferrous alloys by plasma-electrolytic oxidation (PEO). In this work, the study is focused on the effect of current density and negative-to-positive pulse ratio in a wide range of values on the thickness, composition, structure, mechanical and anticorrosive properties of oxide layers on wrought 1560 aluminum alloy (Al – 6.2 wt% Mg). It is found that the oxide layers obtained at the negative-to-positive pulse ratios of 0.7–1.00 and current densities of 9–12 A/dm2 have the best corrosion resistance, while the oxide layers obtained in the “symmetrical” mode and in the “soft sparking” modes at the negative-to-positive pulse ratios of 1.0–1.3 and current densities of 12–18 A/dm2 have the higher hardness and the best wear resistance.