Polyvinyl alcohol/polyethylene glycol composite hydrogel parceling on aluminum: Toward more robust micro-arc oxidation coatings

• Published in: Ceramics international Vol. 49; no. 8; pp. 13081 - 13091
• Main Authors: Jia, Endong, Lu, Hailin, Xu, Guangshen, Xue, Bowen, Wang, Changkai, Chai, Guiquan, Yang, Huiyun, Li, Jianhui
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.04.2023
• Subjects: Corrosion resistance; Hydrogel; Micro-arc oxidation (MAO); Tribological properties; Corrosion resistance; Hydrogel; Tribological properties; Micro-arc oxidation (MAO)
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2022.12.184

Micro-arc oxidation (MAO) technology is an important approach for improving the surface wear and corrosion resistance of aluminum (Al). It forms a dense ceramic oxide coating on the surface of Al through the cooperation of a special MAO power supply and electrolyte, thereby protecting the substrate. A hydrogel composed of polyvinyl alcohol (PVA) and polyethylene glycol (PEG) prepared with an aqueous electrolyte was used to parcel Al disk before MAO. The hydrogel contains a large number of hydroxyl functional groups that increase the dielectric constant and surface activity of Al, resulting in a more dense and wear-resistant coating (Al-MAO-GEL) by the reaction. The surface appearance, elemental composition, distribution, concentration and phase composition of the Al-MAO-GEL coating were analyzed using scanning electron microscope, energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and X-ray diffractometry. The tribological properties and corrosion resistance of the coating were assessed by friction and corrosion tests, indicating that the Al-MAO-GEL coating was protective. This study provides insights into modifications to improve MAO coatings, thereby expanding the service life and possibilities of Al and Al alloy tribological components.