Self-healing ceramic coatings that operate in extreme environments: A review

This paper provides an overview of the latest research developments in the design and exploration of ceramic coatings with high temperature adaptive behavior. The adaptive behavior, triggered by thermal or thermomechanical stimulus, may be used to create smart surfaces that are able to change their chemistry and structure to achieve the desired functionality. The initial focus of the paper will be to provide an overview on the basics of self-repairing materials. This will be followed by a brief outline of the work that has been reported on self-healing/adaptive mechanisms in bulk ceramics. We will then focus on providing a thorough review on self-healing ceramics with a focus on adaptation/healing in tribology as well as thermal barrier, anticorrosion, and oxidation resistant coatings. Advantages and disadvantages of using hybrid polymer-ceramic coatings will also be discussed toward the end of the article. This overview will provide a fundamental understanding of the changes in the structural and chemical properties of these materials and how that correlates to their performance. This review also includes a discussion on anticipated future developments in this important and upcoming area of research.