Composite materials are made by combining two or more different materials. X-ray computed tomography (CT) visualizes differences in X-ray absorbance in an object as contrast in the image. For example, ceramics, resin, and voids are represented by different gray levels. Rigaku’s high-resolution 3D X-ray microscope, nano3DX, an X-ray CT instrument, is capable of acquiring images of a sample at sub-micron-scale resolution and showing a zoomed image of the sample’s internal structure in three dimensions. This allows you to understand the dispersion of each component that affects the properties of the composite, presence/absence of separation at the boundary surface of the material, and the size of the voids.