Rate-dependence Analysis of Interlaminar Stresses of Thick Thermoplastic Composite AS4-PEEK Laminate

Abstract

In this study, the interlaminar stresses for a thick AS4-PEEK laminate [0/±45/90]2s for three different strain rates are computed and investigated using the finite element procedure developed with the finite element program generator (FEPG) of Beijing Fegensoft Corporation Limited. The three-dimensional distribution plots at different interfaces are given. According to the interlaminar stress results for three different strain rates, the effects of the strain rates on the interlaminar stresses at different interfaces are elucidated. The interlaminar shear stresses τzx at the interfaces increase along with an increase in strain rates, but when the strain rate reaches a certain extent, the effects of the strain rates on the interlaminar shear stresses are gradually weakened. The effects of the strain rates on the interlaminar shear stresses τzy at the interfaces are similar. Except for the interlaminar normal stresses at the interface +45%-45, their strain rate dependence effects are slight. As far as the different interfaces are concerned, the effects of the strain rates on the interlaminar stresses at the interface 0%90 are the weakest, and the effects on the interlaminar stresses at the interface +45%-45 are the strongest. Furthermore, the variation circumstances of the interlaminar stresses along the free edges are studied and the interlaminar stresses for two strain rates at this location are analyzed.