Projection angle dependence in grating-based X-ray dark-field imaging of ordered structures.

Area of Science:

• Physics
• Materials Science
• Imaging Technology

Background:

• Hard X-ray imaging techniques are advancing with grating-based Talbot-Lau interferometers.
• Differential phase-contrast imaging offers enhanced contrast and structural information beyond traditional X-ray attenuation.
• Dark-field imaging reveals microstructural features, even at sub-resolution scales.

Purpose of the Study:

• To extend existing 2D models of dark-field contrast to 3D.
• To analyze dark-field contrast tomography (CT) for anisotropically structured materials.
• To exploit grating-based X-ray interferometry for detailed material analysis.

Main Methods:

• Utilizing a grating-based Talbot-Lau interferometer for hard X-ray imaging.
• Acquiring differential phase-contrast and dark-field images.
• Performing dark-field contrast tomography on anisotropic materials like carbon fiber reinforced carbon (CFRC).

Main Results:

• Dark-field signals correlate with micro-porosity and micro-fiber presence and orientation.
• Unidirectional gratings provide anisotropic structural information based on scattering plane sensitivity.
• The study demonstrates the extension of 2D dark-field analysis to 3D tomographic data.

Conclusions:

• Dark-field contrast tomography is valuable for characterizing anisotropic materials.
• The technique provides insights into microstructural properties not visible with conventional X-ray methods.
• This work advances the application of X-ray interferometry for detailed material science investigations.