Imaging the Life-Cycle of CMCs Using High-Resolution X-Ray Computed Tomography

Abstract

In this study, the entire life cycle of a ceramic matrix composite (CMC) manufactured using polymer infiltration and pyrolysis (PIP) is imaged using high-resolution X-ray micro-computed tomography (μCT). The entire PIP process is imaged ex situ to capture the evolution of voids and shrinkage cracks during laminate densification. After manufacturing, two specimens are extracted from the CMC laminate, and subsequently tested to failure in flexure and tension at 1000°C. Gray-scale image segmentation methods are used to quantify the evolution of porosity within the microstructure during PIP processing. X-ray μCT image results from in situ testing are qualitatively examined to quantify presence of individual fiber breaks, fiber pull-outs, matrix cracking, fiber-matrix decohesion, to name a few. These results are used to motivate development of new algorithms for segmentation of microstructural features from X-ray μCT data sets.