PREDICTION OF THE MECHANICAL BEHAVIOR OF A MINICOMPOSITE BASED ON GREY VERHULST MODELS

The tensile behavior of a C/SiC minicomposite fabricated by chemical vapor infiltration was examined and the associated damage evolution was monitored by using acoustic emission (AE) technique. Both the tensile behavior and the associated AE evolution of the minicomposites can be well characterized by three regimes including matrix cracking emergence, multiplication followed by matrix cracking saturation. The grey Verhulst model and inverse Verhulst model were established for the evolution of the cumulative AE energy and the stress-strain behavior, respectively. Excellent agreement between predictions and experimental results was obtained for both the grey models, which indicates the nature of intraspecific competition for these matrix cracks in the minicomposites studied. Such robust relationships can be further applied to model the constitutive behavior of other ceramic composite systems.