Abstract:

The integration of ceramic matrix composites with environmental barrier coatings (CMC-EBC) represents the most promising thermal structural material system in the aerospace field. This paper provides an overview of the advancements in research on the failure mechanisms and numerical models of CMC-EBC. It commences with a concise review of the evolution and primary fabrication techniques of CMC-EBC material system. Subsequently, it summarizes the typical damage modes and failure mechanisms of CMC-EBC under operational conditions, identifying that the interplay between the CMC preform structure, porosity defects, and EBC inner cracks is a critical determinant of the material’s lifespan. However, current mechanistic studies are chiefly focused on the performance evaluation of the coating itself and its susceptibility to environmental factors, disregarding the synergistic effects of the coating and composite architecture during damage progression. This review proceeds with an examination of the history and current status of research on failure simulation and prediction models for CMC-EBC, highlighting issues related to modeling environmental factors and simulating coupled damage evolution. Though much effort has directly developed separate failure models for CMC and EBC, predicting the failure of CMC-EBC components should account for the coupling effects between damage evolution and microstructure. In conclusion, this review offers a perspective on development and service performance prediction methods for CMC-EBC system, which points out that considering the interdependent failure modes of the CMC substrate and EBC is pivotal. Integrated design and analysis of structural and functional aspects are emerging trends in CMC-EBC component research.

Key words: ceramic matrix composite, environmental barrier coating, damage coupling, failure model, integrated design, review