CORROSION RESISTANCE OF ALUMINUM ALLOY ANODIC FILM SEALED BY NICKEL ACETATE

Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization were used to study the corrosion behavior of different sealed aluminum alloy anodic films in 1mol/L NaCl solution.The anodic films were sealed by the methods of boiling water,potassium dichromate and nickel acetate,respectively. The surface morphology and element contents of anodic oxide films were studied with field emission scanning electron microscopey (SEM) and X-ray energy dispersive spectroscopy (EDS).The nickel acetate sealing could make the anodic films more uniform and nickel was present through the whole depth of the anodic films.Nickel acetate sealed films provided relatively high resistance in both acidic and basic solutions.