Fracture behavior of carbon fiber reinforced plastics determined by the time–frequency analysis method

摘要: Fourier transform has been used to study the frequency characteristics of a signal. However, based on and power spectrum alone, it is hard tell whether or not content signal evolves over time, even though phase relates time shifting. On other hand, except for few special cases, majority signals encountered in real world change with time. Recently, overcome problem that unable represent nonstationary signal, time–frequency analysis methods can simultaneously information about have developed. In this study, damage process cross-ply carbon fiber reinforced plastics (CFRP) during monotonic tensile test was characterized by acoustic emission (AE). Different laminated types CFRP were determine AE frequency. The method found be useful determination fracture mechanism (such as, matrix cracking, debonding–delamination, fracture). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1659–1664,