METHOD OF REJECTION OF DEFECTS IN CARBON FIBER SAMPLES BY PARAMETERS OF ACOUSTIC EMISSION SIGNALS UNDER STATIC AND THERMAL LOADING

Abstract

A method for rejecting defects in T 800 carbon fiber samples loaded with a static tensile load at an interval of ΔP = 10 kN until complete destruction is proposed. One part of the samples was loaded at a temperature of 20 °C, and the other part was subjected to simultaneous static loading and heating to a temperature of 100 °C. Samples made of carbon fiber with a size of 600×100×0.9 mm were made using autoclave and vacuum technologies at temperatures of 80; 135; 180 °C. the process of destruction of samples was controlled by acoustic emission (AE). To perform defect rejection, informative parameters of AE signals (structural coefficient and median signal amplitude) were used. The critical damage associated with the breaking of the fibers in the composite corresponded to AE signals with a structural coefficient less than a threshold and a median of amplitudes greater than a threshold.