Analysis of damage mechanisms and associated acoustic emission in two SiC/[Si-B-C] composites exhibiting different tensile behaviours. Part I: Damage patterns and acoustic emission activity

The present work deals with two SiC/[Si-B-C] composites exhibiting different mechanical behaviours under tensile testing: low strain to failure for the one, high strain to failure for the other with similar ultimate strength. In the present Part I, mechanical hysteresis loops of stress-strain curves are analysed, and detailed cracking patterns are presented and quantified for both materials. The difference between both composites is explained by different values of the interfacial shear stress. Acoustic emission activities are compared as regards to the damage accumulation scenarios. In a companion paper [Moevus M, Godin N, Rouby D, R'Mili M, Reynaud P, Fantozzi G, et al. Analyse of damage mechanisms and associated acoustic emission in two SiC/[Si-B-C] [23] composites exhibiting different tensile curves. Part It: Unsupervised acoustic emission data clustering. Comp Sci Technol, in press], the AE data will be submitted to an unsupervised clustering procedure in order to distinguish the different damage mechanisms. (c) 2007 Elsevier Ltd. All rights reserved.