Investigation of micro-arc oxidation coating growth patterns of aluminum alloy by two-step oxidation method

Schematic diagrams (A-B-C-D in P-electrolyte and A-B-C′-D′ in Si-electrolyte) illustrate the MAO reaction processes. SEM images obtained by two-step oxidation show the coating growth patterns in P-electrolyte (E) and Si-electrolyte(E′).