Research Progress on Sintering Resistance of Ceramic Thermal Protection Coatings

Ceramic thermal protective coatings during long-term service in high-temperature environments are prone to micropore shrinkage, grain coarsening, and porous structure collapse, leading to severe densification. This consequently degrades the durability and reliability of the ceramic coatings. This paper elucidates the sintering densification mechanism of ceramic coatings, analyzes innovations in material systems and multidimensional structural design strategies, and summarizes the state-of-the-art research progress on anti-sintering densification of ceramic coatings. The limitations of conventional techniques that inhibit high-temperature sintering densification via “passive pore retention” are highlighted. A novel strategy based on phase transformation-induced pore formation for achieving “active in situ pore generation” is explored. On this basis, future research directions for enhancing the anti-sintering densification performance of ceramic thermal protective coatings are proposed.