3D reconstruction of plasma electrolytic oxidation coatings on Mg alloy via synchrotron radiation tomography

Plasma electrolytic oxidation (PEO) is a well-known surface treatment for Mg alloys, while high porosity is an issue to achieve long-term corrosion protection. Nevertheless, the presence of inherent porosity can be turned into advantage while used as nano/micro-structured reservoir of corrosion inhibitors or functional agents next to Mg surface providing an active corrosion protection and multi-functionality. For the first time, we report here the 3D internal architecture of PEO coated Mg via synchrotron-based microtomography. The pore characteristics have been qualitatively and quantitatively investigated to unveil the formation of the coating porosity and potential incorporation of functional elements in the pores.