Surface Modification of Aluminum 6061-O Alloy by Plasma Electrolytic Oxidation to Improve Corrosion Resistance Properties

In the present investigation, the plasma electrolytic oxidation (PEO) process was employed to form aluminum oxide coating layers to enhance corrosion resistance properties of high-strength aluminum alloys. The formed protective coating layers were examined by means of scanning electron microscopy (SEM) and characterized by several electrochemical techniques, including open circuit potential (OCP), linear potentiodynamic polarization (LP) and electrochemical impedance spectroscopy (EIS). The results were reported in comparison with the bare 6061-O aluminum alloy to determine the corrosion performance of the coated 6061-O alloy. The PEO-treated aluminum alloy showed substantially higher corrosion resistance in comparison with the untreated substrate material. A relationship was found between the coating formation stage, process parameters and the thickness of the oxide-formed layers, which has a measurable influence on enhancing corrosion resistance properties. This study demonstrates promising results of utilizing PEO process to enhance corrosion resistance properties of high-strength aluminum alloys and could be recommended as a method used in industrial applications.

Automated summary

This study utilized the plasma electrolytic oxidation (PEO) process to enhance the corrosion resistance properties of high-strength aluminum alloys by forming aluminum oxide coating layers. The PEO-treated aluminum alloy showed significantly higher corrosion resistance compared to the untreated substrate material, with a relationship found between the coating formation stage, process parameters, and the thickness of the oxide-formed layers impacting corrosion resistance properties. The results demonstrate promising potential for industrial applications.