SIMULATION OF CRACK PROPAGATION IN FILLED ELASTOMERS

Abstract

The results of computer simulation of the crack growth in an elastomeric nanocomposite and its interaction with microscopic strands that can occur between adjacent closely spaced filler particles during material loading are presented. The hypothesis that elastomeric material is able to withstand significantly greater loads under uniaxial tension compared to other types of stress state (at the same intensity of deformation) is used in the simulation. A strength criterion taking into account this effect (maximum strength is achieved with uniaxial tension) is developed. Numerical studies showed that, with a fairly close approach of the crack front to the gap between filler particles, the formation of a reinforced microstrand is possible, connecting the crack "shores" and, accordingly, preventing its further progress. It is well known that the addition to elastomer of a rigid filler with good adhesion to matrix allows the resulting composite to withstand a significantly higher external load compared to unfilled material. This is due to the fact that micro-breaks in the material appear mostly on structural defects. So nothing prevents the crack growth in a material without filler. However, microstrands that form between close placed filler particles in an elastomeric composite can appreciably delay its propagation.