An improved model including plasticity for the prediction of the stress in fibres with an interface/interphase region

From the analytical models currently available for predicting the stresses in and around an isolated fibre in an elastic polymer matrix, one analytical model proved to be the most accurate. Therefore a more comprehensive model named the 'plasticity model' has been developed by incorporating the elasto-plastic properties of the matrix and the interphase. The main advantage over earlier models is that de-bonded and interphase regions can be included. The predictions of the plasticity model have been validated using an elasto-plastic finite element model for a glass fibre/epoxy composite. This model is a simple numerical model of the stress transfer between fibre and matrix with/without an interphase and as such can be used for modelling fibre stress data from Laser Raman Spectroscopy and for more precise analysis of the fragmentation test data.