Strain-rate Dependence of Interlaminar Stress Fields in the Vicinity of Free Edges of AS4-PEEK Composite Laminates Under Uniaxial Tension

Using finite element program generator (FEPG) of Beijing Feijian Software Corporation, a relative finite element procedure is developed for the three-dimensional viscoplasticity model which can characterize well the nonlinear behavior and strain-rate dependence behavior of thermoplastic composite, AS4-PEEK. Interlaminar stresses of angle-ply laminates [±θ] s for different strain rates under uniaxial tension are calculated. The effects of the variation of strain rates on interlaminar stresses in the vicinity of free edges of AS4-PEEK composite laminates are investigated. From the three-dimensional plots of the interlaminar stresses, it can be seen that distant free-edge effects and end-edge effects exist in the angle-ply laminates [±θ] s . The interlaminar stresses in free-edges and two ends increase with increasing strain rates. The extents to which the strain rates affect interlaminar stresses are depicted.