Numerical modelling of the fracture behaviour of a glass matrix composite reinforced with alumina platelets

In this work the fracture behaviour of a composite material constituted by a borosilicate glass matrix reinforced with Al2O3 platelets is studied by means of a numerical model. This material, which was experimentally investigated in a previous paper, is characterised by the presence of thermal residual stresses that arise upon cooling from the processing temperature due to the thermal expansion coefficients mismatch between the matrix and the reinforcements. A numerical model based on finite element simulations of realistic composite microstructures was adopted for the present material. The crack propagation was studied using finite elements coupled with selected failure criteria (Griffith and Weibull approaches) implemented inside the elements. Computational determination of crack propagation during failure is compared with previously obtained experimental data and microscopy images of platelet-crack interactions, showing that the model provides results in good agreement with the experimental observations. (C) 2002 Elsevier Science Ltd. All rights reserved.