Interlaminar Stress Analysis of Thick Thermoplastic AS4-PEEK Composite Laminates

The three-dimensional viscoplasticity model, which can characterize the nonlinear behavior and the strain-rate dependence behavior of the thermoplastic composite AS4-PEEK, is realized through the procedure developed. The interlaminar stresses at different interfaces for two kinds of strain rates are computed. Depending on the plots of the three-dimensional distribution of the interlaminar stresses, the distribution characters of the interlaminar stresses at the different interfaces are analyzed and the major factors that may result in delamination are demonstrated. According to the computing results of the interlaminar stresses for the different strain rates, the effects of the variation of the strain rates on the interlaminar stresses are studied.