Broadband Laser-Ultrasonic Spectroscopy for Quantitative Evaluation of Porosity Effect on Acoustic Attenuation and Phase Velocity in CFRP CompositesстатьяЭлектронная публикация
Место издания:NDT.net Open Access Database of Nondestructive Testing (NDT)
Аннотация:This work aims at applying the method of broadband laser-ultrasonic spectroscopy for quantitative evaluation of the effect of isolated dispersed voids and extended interply delaminations on the acoustic attenuation and on the phase velocity in CFRP composite laminates. The specimens have different total porosity levels up to 10.5% determined by the X-ray computer tomography. The ultrasonic attenuation resonance and the corresponding jump of the phase velocity are observed in all specimens governed by their periodic layered structure. The absolute maximum and the frequency bandwidth of the resonance attenuation peak, as well as the low-frequency velocity dispersion depend on the total porosity level formed by the predominant imperfections in the composite structure, either isolated microscopic dispersed spheroidal voids or extended interply delaminations.