CMC-EBC损伤耦合机理及一体化设计研究进展

Progress of Damage Coupling Mechanism and Integrated Design Method for CMC-EBC

陶瓷基复合材料与环境障碍涂层组合(CMC-EBC)是目前航空航天领域最具应用前景的热结构材料体系。本文对CMC-EBC失效机理与分析模型的研究进展进行综述。首先,简要回顾了CMC-EBC材料体系的发展及主要制备工艺。然后,综述了CMC-EBC在服役环境下的主要损伤模式与失效机理,总结发现CMC预制体结构、孔洞缺陷和EBC内裂纹等损伤演化相互影响,这种细观损伤模式的耦合是决定其寿命的关键因素之一,但目前的机理研究主要集中于涂层本身性能及其受环境因素的影响,缺乏对涂层和复合材料编制结构在损伤演化过程中协同效应的考虑。接下来,详细分析了CMC-EBC的失效模拟与预测模型研究的历史与现状,指出其中存在的问题,包括环境因素建模方法和损伤耦合演化模拟技术。目前大部分工作致力于分别开发CMC和EBC的失效模型,而对于CMC-EBC构件的失效预测应考虑其损伤演化与微观结构之间的相互耦合影响。最后,对CMC-EBC材料体系研发与服役性能预测方法进行了展望,认为CMC本体和EBC失效模式相互耦合,开展结构功能一体化设计和分析是CMC-EBC构件研究的趋势。

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.