Self‐Healing Coatings for Corrosion Protection of Magnesium and Aluminum Alloys: Intrinsic, Extrinsic, and Controlled‐Release Strategies

Light alloys, particularly magnesium and aluminum, are recognized for their low density, high specific strength, and excellent processability, leading to their widespread use in aerospace and other sectors. However, their intrinsic susceptibility to corrosion remains a critical bottleneck limiting their widespread implementation. Although polymer barriers effectively isolate substrates from corrosive environments, they are vulnerable to microcracks and damage under rigorous service conditions, leading to premature failure. Consequently, the development of smart coatings with autonomous self‐healing capabilities is imperative. By spontaneously restoring structural integrity upon damage, these coatings significantly extend service life and minimize maintenance requirements. This review summarizes recent advances in self‐healing coatings for light alloys, emphasizing various self‐healing mechanisms and their underlying anticorrosion principles, with the aim of providing insights for their development in aerospace applications.