Design and Multidimensional Screening of Flash-PEO Coatings for Mg in Comparison to Commercial Chromium(VI) Conversion Coating

REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulations demand for an expedient discovery a Cr(VI)-free alternative corrosion protection light alloys even though the green alternatives might never be as cheap current harmful technologies. In present work, flash- plasma electrolytic oxidation coatings (FPEO) with process duration < 90 s are developed on AZ31B alloy in varied mixtures silicate-, phosphate-, aluminate-, fluoride-based alkaline electrolytes implementing density voltage limits. The overall evaluation coatings’ anticorrosion performance (electrochemical impedance spectroscopy (EIS), neutral salt spray test (NSST), paintability) shows that from nine optimized FPEO recipes, two (based phosphate, fluoride, aluminate or silicate mixtures) found to adequate substitute commercially used Cr(VI)-based conversion coating (CCC). best resistance consume very low amount energy (~1 kW h m−2 µm−1). It is also lower consumption process, better resultant coating. superb solid environmentally friendly outlook PEO-based technology may facilitate economic justification industrial end-users current-consuming replacement electroless CCC process.