A Review on the Preparation Methods and Corrosion Behavior of Graphene-Coated Aluminum

Abstract

Aluminum and its alloys feature low weight and high strength. They are widely applied in aerospace, automobile manufacturing, and marine engineering. However, they are highly susceptible to localized corrosion. Such defects can severely restrict the service life of the substrate materials. Pristine graphene exhibits atomic-level compact impermeability, stable chemical inertness, and excellent mechanical properties. It is a promising candidate material for the protection of aluminum substrates. Nevertheless, an electrically insulating interlayer is generally required between pristine graphene and aluminum to achieve reliable protection. This measure avoids the risk of galvanic corrosion. This paper systematically reviews the latest research progress of graphene-based coatings on aluminum, focusing on pristine graphene, graphene oxide (GO), reduced graphene oxide (rGO), and graphene-polymer composite coatings. It focuses on the preparation methods and corrosion protection performance of the materials. This study compares various mainstream preparation technologies in detail. The technologies include chemical vapor deposition, electrochemical deposition, mechanical exfoliation, solution coating, laser induction, and thermal spraying. The corrosion protection mechanism is discussed from three dimensions. The dimensions include physical barrier effect, tortuous path mechanism, and electrochemical protection. Key influencing factors, such as coating defects and environmental conditions, are also investigated. This paper summarizes the application potential of graphene-based coated aluminum in high-end manufacturing fields. It points out the major existing challenges of the material. The challenges involve coating uniformity, adhesion strength, long-term stability, and industrial production. Finally, future research directions are proposed in this work. These directions include the development of innovative coating technologies, the construction of composite protection systems, the design of intelligent self-healing functions, and the exploration of environmentally friendly preparation processes.