LONGITUDINAL SPLITTING AND FIBER BREAKAGE CHARACTERIZATION IN GRAPHITE-EPOXY USING ACOUSTIC-EMISSION DATA

The acoustic response of a specially designed composite tensile specimen was monitored from the onset of loading until fiber breakage and longitudinal splitting were observed. Two distinct subsets of the data were identified using signal amplitude as a filter criteria. Since the position of the paws was known, source location was used to associate the data subsets with either fiber breakage or longitudinal splitting. Subsequent analysis of the two data subsets revealed the relative strength of the signals produced by each failure mechanism. Finally, the issue of signal attenuation was addressed, and, in particular, its effect on the resulting acoustic emission (AE) parameters.