Numerical modelling of damage susceptibility of an inhomogeneous representative material volume element of polymer composites

A microstructure sample size capturing the inhomogeneity of the reinforcing phase of a composite material was described in a preceding paper. Here using a finite element method, the transverse damage behaviour of a number of microstructural samples has been investigated. The samples ranged in size from 300 μm × 300 μm to 180 μm × 180 μm, and the finite element model was based on fibre centroid and fibre diameter data from a cross-ply laminate. Comparing normalized stiffness curves for the samples suggested that a sample size of 300 μm × 300 μm, containing approximately 400 fibres, is necessary to capture the effects of microstructural inhomogeneity on the damage susceptibility of the analysed microstructure. Selecting this size as suitable for a representative volume element (RVE) corresponds to a 0.10 significance level in the Kolmogorov goodness- of-fit statistical test described in an earlier paper.