Microstructural characteristics of oxide layers formed on Mg-9Â wt%Al-1Â wt%Zn alloy via two-step plasma electrolytic oxidation

- The oxide layer on Mg alloy sample treated by two-step PEO coating was fabricated.
- The breakdown voltage of sample via two-step PEO coating was observed to be ∼475 V.
- Mg2Zr5O12 and ZrO2 were synthesized in the oxide layer via two-step PEO coating.