Visualization of subsurface damage in woven carbon fiber-reinforced composites using polarization-sensitive terahertz imaging

Dong, Junliang, Pascal Pomarède, Lynda Chehami, Alexandre Locquet, Fodil Meraghni, Nico F. Declercq, and D. S. Citrin. "Visualization of subsurface damage in woven carbon fiber-reinforced composites using polarization-sensitive #terahertz imaging." NDT & E International (2018).

for full paper see https://www.sciencedirect.com/science/article/pii/S0963869518301610

Abstract

Polarization-sensitive #terahertz imaging is applied to characterize subsurface damage in woven carbon fiber-reinforced composite laminates in this study. #Terahertz subsurface spectral imaging based on #terahertz deconvolution is tailored and applied to detect, in a nondestructive fashion, the subsurface damage within the first ply of the laminate caused by a four-point bending test. Subsurface damage types, including matrix cracking, fiber distortion/fracture, as well as intra-ply delamination, are successfully characterized. Our results show that, although the conductivity of carbon fibers rapidly attenuates terahertz propagation with depth, the imaging capability of #terahertz radiation on woven carbon fiber-reinforced composites can nonetheless be significantly enhanced by taking advantage of the #terahertz polarization and terahertz deconvolution. The method demonstrated in this study is capable of extracting and visualizing a number of fine details of the subsurface damage in woven carbon fiber-reinforced composites, and the results achieved are confirmed by comparative studies with X-ray tomography.

… thickness direction). The commercial THz time-domain spectroscopy (TDS) system (Teraview TPS Spectra 3000), which was employed in this study, is shown schematically.....

for more information about TeraView see: teraview.com