Acoustic and Emission Analysis of the Defect Nucleation Process in Carbon Fiber Reinforced Plastic Samples

Abstract

The results of acoustic emission (AE) control of samples consisting of nine monolayers of [±45/90/03/90 /±45] pre-impregnated material Torayca T800 with geometric dimensions of 600×100×0.9 mm are considered. A hole with a diameter of 12 mm was made in the center of each sample. Two samples were exposed to a positive temperature T = 100 °C, three samples were tested at a temperature T = 20 °C. The location of AE signals during loading is shown. The analysis of the main informative parameters of AE signals recorded in the working area of the samples is carried out. Using cluster analysis of the digital form of AE signals, three types of clusters are determined. The first type of clusters was characterized by AE signal frequency exceeding 175 kHz, and a relatively large level of the MARSE energy parameter. AE signals with lower MARSE values and a median frequency not exceeding 170 kHz when the sample was heated and not exceeding 140 kHz when loading without heating were observed in the second type of clusters. The third type of clusters was formed from AE signals whose frequency exceeded 400 kHz, and the MARSE energy parameter was 20 mV∙μs. Such clusters were characteristic only for samples tested at a temperature of T = 20 °C.