Damage mechanisms of a woven SiC/SiC composite: Modelling and identification

Different matrix microcracking mechanisms are observed in ceramic-matrix composites under complex loading conditions. These mechanisms are introduced in the proposed model by using an anisotropic damage theory, which rakes into account the effects due to microcrack opening and closure, according to the state of the stress tensor (the behaviour is different in tension and in compression). One difficulty is the identification of this model for the woven SiC/SiC composite under study. Classical uniaxial tests (at 0 degrees and 45 degrees) are not sufficient to identify the model completely. A combined biaxial tension test is defined in order to determine the missing parameters. Internal pressure rests on tubes qualitatively validated the model. (C) 1996 Elsevier Science Limited