Challenges for grating interferometer X-ray computed tomography for practical applications in industry

X-ray imaging methods, such as conventional X-ray computed tomography (XCT) based on absorption, are essential techniques in various domains, for example medicine and materials science. In the last 15 years, an important innovation in X-ray imaging technology has emerged through the introduction of Talbot-Lau grating interferometry (TLGI)([1-4]). Using this imaging technique with three different gratings, the extraction of attenuation contrast (AC), differential phase contrast (DPC) and dark-field contrast (DFC) information has become available in lab-based XCT systems. In this contribution, the usefulness of TLGI-based XCT for different applications in industry and materials science is demonstrated. DPC has advantages in the discrimination of materials with similar X-ray attenuation, such as water and epoxy, and is less prone to metal artefacts. In comparison, DFC is beneficial for the characterisation of polymeric foams and for the detection of carbon yarn structures and damage (cracks, microvoids, etc) in different kinds of polymer. The anisotropy of DFC can be used to combine the results of two successive DFC measurements at 0 degrees and 90 degrees, allowing the visualisation and quantification of the weaving pattern of a carbon fabric in 3D.