Damage Evolution and Thermoelastic Properties of Composite Laminates

An analytic model for the prediction of the thermoelastic properties of micro cracked composite laminates is presented. The expression for the calculation of en ergy release rates due to growth of micro cracks is also provided. Numerical results are presented that show that the present method, to a very good accuracy, can predict ther moelastic properties of micro cracked laminates at varying crack densities and layup con figurations. In addition, a resistance curve behavior of the energy release rate is observed for both carbon/epoxy and glass/epoxy composite laminates. The reasons for this R-curve behavior are discussed. Criteria that govern the initiation and growth of micro cracks in composite laminates are discussed and compared to experimental data.