Synchrotron refraction CT and Synchrotron Bragg magnification CT for NDE

X-ray refraction topography techniques are based on ultra-small angle scattering by micro-structural elements causing phase-related effects such as refraction and total reflection at a few minutes of arc as the refractive index of X-rays is nearly unity. The refraction contrast is several times higher than true absorption and results in images of cracks, pores and fibre debonding separations below the spatial resolution of the detector. In most cases the investigated inner surface and interface structures correlate to mechanical properties. For the exploration of micro structured materials the refraction technique has been improved by a 3D Synchrotron Refraction Computed Tomography test station. The specimen is placed in an X-ray beam between two single crystals, which suppresses all sample scattering. In addition, an asymmetric cut second crystal can magnify the image up to 50 times revealing nano meter resolution. The technique is an alternative to other attempts on raising the spatial resolution of CT machines.