A review on the failure behavior and countermeasures of thermal barrier coatings

Thermal barrier coatings are widely used in high-temperature components in aircraft thrusters, power generation, and marine engines, enabling gas turbines to operate at elevated temperatures for extended periods by reducing the superalloys' surface temperature. During service, high-temperature oxidation, hot corrosion, and sintering occur inside the thermal barrier coatings, resulting in changes in the macro and microstructure of the coatings, and thermal-mechanical properties degradation, eventually leading to coating failure. The main factors that lead to the failure of thermal barrier coatings and affect the life of thermal barrier coatings are reviewed, including the formation of thermally grown oxides on the surface of the bond coat, the corrosion caused by the deposits on the surface of the coating and the sintering of the high-temperature ceramic layer, and the failure mechanism of the coating is analyzed. The countermeasures to prolong the service life of coatings are reviewed from thermal barrier coating materials, coating structure, coating preparation methods, and post-treatment.