Barely visible impact damage (BVID) can cause serious issue for composite structures, due to sub-surface damage seriously reducing the strength of the material without showing easily detectable surface signs. Dark-field imaging measures ultra-small angle scattering caused by microscopic features within samples. It is sensitive to damage in composite materials which would otherwise be invisible in conventional radiography. Here we demonstrate BVID detection with speckle-based dark-field imaging, a technique requiring only sandpaper (to create the speckle-pattern) in addition to a conventional X-ray imaging setup to extract the dark-field imaging. We demonstrate that the technique is capable of detecting both matrix cracking and delaminations by imaging materials susceptible to these failure mechanisms.
@article{arxiv.2504.11727,
title = {Contrast Enhancement of Barely Visible Impact Damage using Speckle-Based Dark-Field Radiography},
author = {Ronan Smith and Gregor Bortsnar and Vittorio Di Trapani and Ginevra Lautizi and Ludovic Broche and Lukas Helfen and Daniel Bull and Richard Boardman and S. Mark Spearing and Ian Sinclair and Mark Mavrogordato and Pierre Thibault},
journal= {arXiv preprint arXiv:2504.11727},
year = {2025}
}