A comparative and critical study of X-ray CT and neutron CT as non-destructive material evaluation techniques

For years computerized X-ray tomography has been widely used as a medical diagnostic tool. This nondestructive technique soon turned out to be an important research tool for a wide variety of scientific subjects. For material research medical CT, microCT, and since very recently nanoor sub-micro CT are being used as non-destructive material evaluation techniques for engineering and geology purposes. The fact that X-ray CT visualizes the internal structures of natural building stones and yields information on porosity values and pore-size distributions, is a major advantage for the study of their conservation. The penetration of fluids like water, consolidants or water repellents inside porous materials is a hot topic when dealing with conservation and restoration research. Only very recently high-speed neutron tomography has