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NON-DESTRUCTIVE 3 D STRUCTURAL STUDIES BY X-RAY MICROTOMOGRAPHY

X-ray microtomography (XMT) is an evolving form of 3D X-ray microscopy that gives quantitative information on linear attenuation coefficients at a scale of 2 to 100 μm. The method is non-destructive, so that local changes in microscopic structure can be studied between successive applications of externally induced changes, e.g. mechanical or chemical processes. Applications of our laboratory-based XMT systems are illustrated by studies of biological mineralized tissues and in materials science. As regards 1st generation XMT systems, the ability to record attenuation spectra of elements with accessible absorption edges is exploited in studies of the ingress of KI into calcified tissues. Our novel high definition 4th generation cone-beam XMT scanner can image specimens up to 60 mm diameter at resolutions up to 8 μm. Applications include studies of host response to implants in bone, crack opening as a function of load in compact tensile samples of Al-Li 2090 using an in situ loading stage, and in vitro acid demineralization in whole teeth.