Stochastic analysis of inter- and intra-laminar damage in notched PEEK laminates

Abstract

This paper presents a finite element model to predict the progressive damage mechanisms in open-hole PEEK (Poly-Ether-Ether-Ketone) laminates. The stochastic laminate's properties with non-uniform stress distribution are consid- ered from element to element using the Gaussian distribution function. The failure modes considered are: fiber tension/ compression, matrix tension/compression, fiber/matrix shear, and delamination damage. The onset of damage initiation and propagation are predicted and compared with three different failure criteria: strain-based damage criterion, Hashin-based degradation approach and stress-based damage criterion which is proposed by the authors of the present work. The inter- laminar damage modes associated with fiber/matrix shearing and delamination are modeled using the cohesive elements technique in ABAQUS™ with fracture energy evolution law. Mesh sensitivity and the effect of various viscous regulariza- tion factors are investigated. Damage propagation and failure path are examined by re-running the program for several times.