ABSTRACT
Plasma electrolytic oxidation (PEO) treatment was performed on squeeze cast AZ31 alloy and Al18B4(0)33w/AZ31 composite. Scanning electron microscope (SEM) was employed to characterize the surface morphology and cross-section microstructure of the coating. The phase structures of the PEO coating were analyzed by X-ray diffraction (XRD). The corrosion resistance of the PEO coating was evaluated by electrochemical method. The results showed that the Al18B4O33 whisker on the surface of the composite was decomposed and MgAl2O4 was formed in the PEO coating layer of Al18B4(0)33w/AZ31 composite during PEO treatment. As a result, the electrochemical corrosion potential of the PEO coated Al18B4(0)33w/AZ31 composite was increased compared with that of AZ31 alloy.
keyword : plasma electrolytic oxidation, PEO, Al18B4O33/AZ31 composite, corrosion resistance
