INFLUENCE OF INTERFACIAL MICROCRACKS ON THE ELASTIC PROPERTIES OF COMPOSITES

A model is established to quantify the influence of interfacial microc racks on the elastic properties of a particulate composite using a com bination of theoretical and finite element analysis. A unique way to c onstruct physical models which could accommodate both crack size and c rack density is proposed. Based on energy principles, the influence of a dilute concentration of interfacial microcracks is first studied. T he case of a finite concentration of microcracks is solved subsequentl y by combining the dilute concentration solutions and the differential scheme. Both cases agreed well with existing composite theories for t he limiting condition of complete decohesion. The final model predicts the effective elastic properties as functions of both crack size and microcrack density.