Matrix cracking evolution

In addition to these screening effects, the actual evolution of matrix cracks at stresses above amc is governed by statistics that relate to the size and spatial distribution of matrix flaws. If this distribution is known, the evolution can be predicted. Such statistical effects arise when the matrix flaws are smaller than the transition size, a at which steady state commences (Eqn. (36)). In this case, a flaw size distribution must be combined with the short crack solution for K,ip (Eqn. (37)) in order to predict crack evolution. At the simplest level, this... 

Fig. 1.24 (a) Simulation of crack evolution for various matrix flaw distributions characterized by Xs when the shape parameter matrix crack density with stress for unidirectional SiC/CAS. 

Figure 5. Digitized images from 16-mmfilm, showing the evolution of local bowing of a brittle matrix crack past tough PC spheres, R/L = 0.125.

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