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DOE OSTI · 2396357

Stochastic microstructural analysis of ceramic matrix composites using a high-fidelity multiscale framework

Khafagy, Khaled H.·Venkatesan, Karthik R.·Balusu, Kranthi·Datta, Siddhant·Chattopadhyay, Aditi
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Abstract

This paper presents a high-fidelity multiscale framework to simulate the mechanical behavior of ceramic matrix composites (CMCs), accounting for the complex micromorphology captured using detailed material characterization. First, high-resolution micrographs are obtained for the specific carbon fiber silicon-carbide-nitride matrix (C/SiNC) CMC to characterize the variability of the architectural features and manufacturing-induced defects at the microscale. An image processing algorithm is then used to precisely estimate the size and distribution of all subscale features and defects from the micrographs. The information is then used to generate a three-dimensional stochastic representative volume element (SRVE) to reconstruct microscale constituents accounting for the variability. As a result, the generated SRVEs are simulated using the high-fidelity generalized method of cells (HFGMC) micromechanics theory to investigate the effects of defects on the elastic properties of C/SiNC CMCs.

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Ceramic Matrix CompositesCritical LoadingHigh Performance ComputingImage SegmentationMaterial PropertiesMechanical PropertiesMicromechanicsMicrostructureProbability Distribution FunctionsScanning Electron Microscope

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Khafagy, Khaled H., Venkatesan, Karthik R., Balusu, Kranthi, Datta, Siddhant, Chattopadhyay, Aditi. 2021-01-04. Stochastic microstructural analysis of ceramic matrix composites using a high-fidelity multiscale framework. https://doi.org/10.2514/6.2021-1350

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