DAMAGE MECHANISMS OF A WOVEN SIC SIC COMPOSITE - MODELING AND IDENTIFICATION/

Different matrix microcracking mechanisms are observed in ceramic-matr ix composites under complex loading conditions. These mechanisms are i ntroduced in the proposed model by using an anisotropic damage theory, which rakes into account the effects due to microcrack opening and cl osure, according to the state of the stress tensor (the behaviour is d ifferent in tension and in compression). One difficulty is the identif ication of this model for the woven SiC/SiC composite under study. Cla ssical 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 pressur e rests on tubes qualitatively validated the model. (C) 1996 Elsevier Science Limited