Influence of inclusion size and strain rate on the interaction between cracking and the matrix-inclusion interface in composites

The critical deflection/penetration behaviour of a crack terminating perpendicular to a circular matrix-inclusion interface under dynamic tensile loadings is simulated numerically. It is found that higher strain-rate loading is necessary for a crack to penetrate through an inclusion with a smaller radius. Moreover, the minimum loading amplitude for penetration increases with the strain-rate, and this strain-rate dependence appears to be independent of the inclusion size and the interfacial strength. Additionally, these results imply that the strain-rate effect of dynamic strength can be induced by the quasi-static structural properties of composites, which is in agreement with the results of previous works.