High-resolution X-ray computed tomography of composite materials

A computed tomography (CT) system was used to produce high-resolution X-ray CT images of microstructural features in metal-matrix and carbon/carbon composite materials. The system, which consists of a conventional 420-kV X-ray source and a specially designed high-resolution linear detector, was designed for high-resolution CT of small (less than 5-mm diameter) objects. Microstructural damage produced by elevated-temperature tensile deformation and thermal cycling was imaged in an alpha-2 TiAl-matrix/SiC-fiber composite. The CT images showed fiber pullout and matrix void formation in the tensile-tested samples, along with matrix microcracking in the thermally cycled samples.