Abstract
The effects of the current density on the micro structure and the corrosion property of the coating on AZ31 Mg alloy processed by the plasma electrolytic oxidation (PEO) were investigated. The present coatings were produced in an acid electrolyte containing K2ZrF6 with three different current densities, i.e., 100, 150, and 200 mA/cm2. From the microstructural observations, as the applied current density was increased, the diameter of micro-pores formed by the plasma discharges with high temperature increased. The coatings on AZ31 Mg alloy were mainly composed of MgO, ZrO2, MgF2, and Mg2Zr5O12 phases. The results of potentiodynamic polarization clearly showed that the PEO-treated AZ31 Mg alloy applied at 100 mA/cm2 of current density exhibited better corrosion properties than the others.
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Lee, K.M., Einkhah, F., Sani, M.A.F., Ko, Y.G., Shin, D.H. (2014). Effects of Current Density on Microstructure and Corrosion Property of Coating on AZ31 Mg Alloy Processed via Plasma Electrolytic Oxidation. In: Alderman, M., Manuel, M.V., Hort, N., Neelameggham, N.R. (eds) Magnesium Technology 2014. Springer, Cham. https://doi.org/10.1007/978-3-319-48231-6_66
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DOI: https://doi.org/10.1007/978-3-319-48231-6_66
Publisher Name: Springer, Cham
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