Composite Sol-Gel (CSG) coatings, which are part of a broad class of sol-gel matrix composites, have received much attention as high performance materials for a wide range of surface engineering applications, such as industrial decorative coating and protective coating. In this study an alumina CSG ceramic has been fabricated by dispersing calcined alumina powder in an alumina sol. The alumina sol acts as a dispersant and sintering accelerator for the calcined alumina. In this study the corrosion behaviour is characterized using Electrochemical Impedance Spectroscopy (EIS) techniques. The corrosion response of the coating has been linked to the structure and the time for solution penetration can be determined using electrochemical signatures.
Keywords: corrosion, thermal spray, coating, cermet