Micromechanical Models for Dielectric Behavior of Ceramic Matrix Composites

The proposed program will enhance material and sensor models to provide improved understanding of dielectric property information regarding Ceramic Matrix Composite (CMC) material condition. These models are to be used to assess thermochemical degradation of CMC’s and also to assess the condition of materials during manufacture. JENTEK has developed a family of electroquasistatic and magnetoquasistatic sensors and arrays that have successfully solved a wide range of previously intractable NDE problems. These sensors and sensor arrays use model-based inverse methods to estimate electromagnetic properties that are correlated with many conditions of interest, such as thermal degradation of component materials. In this program, JENTEK’s Interdigitated Electrode Dielectrometers are being adapted for in-service material evaluation of CMC’s. Micromechanical models are extended to predict dielectric behavior of coated fiber CMC’s and incorporated into anisotropic material representations for dielectric sensor models to determine dielectric properties of the composite constituents. These dielectric properties will then be integrated with a thermostructural analysis to determine CMC component structural integrity. Team members on this program include CMC thermostructural modelers (MR&D), manufacturers (COI Ceramics), and an end user (Pratt & Whitney).