Micromechanical Edge Effects in Glass Matrix Composites

This paper reports on our efforts to demonstrate the significance of free edge effects on the effective response of a unidirectional composite under combined thermal and transverse loading and to validate the predictions of an analytical model through the careful design and testing of composite specimens. Included in this study are the demonstration of potential failure modes and the predictions for the micromechanical stress fields which define damage initiation and the constituent energy release rates governing crack propagation within the constituents and along the interfaces. The theoretical predictions for damage development and propagation are in good agreement with the experimental measurements and observations and demonstrate the importance of free edge stresses in controlling damage initiation and subsequent response.