High resolution x-ray tomography in an electron microprobe

Conversion of an electron microprobe for use as an x-ray microtomograph is described. Only minor modifications are required, indeed several of the utilities of the microprobe can be used to ensure high resolution radiography and tomography. System performance was evaluated by analysis of glass fiber reinforced polymer composites and of a carbonate reservoir rock. Individual glass fibers of 10 and 20 mu m diameter are clearly visible in the former. In the latter, comparison with scanning electron micrographs shows reliable reconstruction of external morphology. In addition, internal pore structure can be studied a posteriori using the tomography data. Spatial resolutions in radiography of better than 3 mu m and in tomography of 10 mu m have been demonstrated. Further improvements to the detector system and increased data handling capacity are possible to achieve 1 mu m resolution tomographic images. (C) 1996 American Institute of Physics.