3D X-ray Computed Tomography (3D X-ray CT)
Selected Publications ►
- Godinho, J. R. A.; Chellappah, K.; Collins, I.; Ng, P.; Smith, M.; Withers, P. J.
“Time-lapse imaging of particle invasion and deposition in porous media using in situ X-ray radiography”, Journal of Petroleum Science and Engineering (2019)
- Godinho, J. R. A.; Kern, M.; Renno, A. D.; Gutzmer, J.
“Volume quantification in interphase voxels of ore minerals using 3D imaging”, Minerals Engineering (2019)
How does it work? ►
The components within a sample are imaged based on the principle, that each material attenuates X-rays differently, depending on its electron density. Therefore, after passing through a sample the X-rays projected on a detector show a shadow of the sample’s components. Acquiring projections while rotating the sample (360 degrees) allows tracking the individual component in space, which enables the construction of the sample in 3D. Normal detectors measure the total amount of X-rays (of all energies), while our special energy sensitive detector allows to resolve the energy spectrum. This helps to identify elements with a k-edge > 23 keV (heavier than Ru).
Important to plan a scan: The resolution is inversely proportional to the field of view. Samples < 2 cm diameter are necessary to achieve the highest resolution (~4 um). Cylindrical samples are ideal but other geometries can be measured without any special treatment. The method is non-destructive.