Modeling of Digital Spectrum Based Ultrasonic Attenuation about Void Content in CFRP

The voids morphological features are correlated with the CFRP porosity and the fraction of voids is nearly a logarithmic normal distribution with the voids´ size.The apparatus employed notebook computer to control signal´s collecting, processing, and displaying. Based on the method of acoustic resistance, this paper described the ultrasonic detection technology for bonded structures of composite materials on modern battleplan. The frequency-domain characteristics of echo can reveal some new information about the bonding defect, which were not evident in time domain.The experiments were performed using practical samples, and the results showed that defects in different samples can be quantitatively identified with high accuracy. Based on the study, an ultrasonic attenuation model of CFRP porosity testing was established in which the voids´ statistical and morphological features were considered.