Impact damage characterization in hybrid fiber-reinforced composites using terahertz imaging in time and frequency domain

A hybrid fiber-reinforced composite laminate with impact damage has been studied via terahertz imaging. Both of the impact-induced intra- and inter-laminar damages are successfully detected. Terahertz C-and B-scans in time domain show the damage evolution throughout the thickness. Intra- and inter-laminar damages at the same interface can be differentiated via polarization-resolved imagings, which can also be located with THz C- and B-scans in frequency domain.