Effect of the nitrogen inducing agents on the corrosion behavior of AlON-Al2O3 coatings prepared by electrolytic plasma processing on an Al6061 alloy

Abstract

The electrolytic plasma processing method was used to prepare AlON-Al2O3 oxide coatings on an Al6061 alloy at room temperature in 15 min at a hybrid voltage with various nitrogen inducing agents. The nitrogen inducing effects were studied by X-ray diffractometer and scanning electron microscopy. The corrosion behavior of the coating was evaluated by electrochemical tests in a 3.5 wt% NaCl solution under static conditions by open circuit potential and potentiodynamic polarization. The results show that NaNO2 is a suitable steady nitrogen inducing agent for preparing a uniform and dense AlON-Al2O3 coating on the Al6061 alloy to protect the substrate.