A new method of characterizing patterns in x-ray tomographic images of a composite specimen

A 5 x 3 mm composite specimen consisting of 50 micron thick aluminum foils and 50 micron thick adhesive tape was scanned by the Fraunhofer-Institute X-ray tomographic scanner for a pixel size of 20 microns. This data was further processed by the convolution backprojection algorithm and several Hamming and exponential filters were employed. The results indicate that different regions of this specimen exhibit a distinct "fractal signature" for a certain type of filter. Characterization guidelines for composite materials have been suggested using this combination of tomographic filters and fractals.