Prediction of interlaminar shear strength of a thermally aged carbon/epoxy composite material by Fourier transform infrared photoacoustic spectroscopy.

Photoacoustic spectroscopy was used to predict the interlaminar shear strength of a carbon/epoxy composite. Samples were artificially aged by exposing the samples to elevated temperatures in an air environment. Short-beam shear tests were performed to determine mechanically the interlaminar shear strength of the samples. Photoacoustic spectra of the samples were also collected and compared to mechanical data. Chemometrics were performed on the spectral and mechanical data, and a good correlation was found between the near surface chemistry of the composite and overall mechanical integrity.