Compressive properties and fracture behavior of two-and-a-half-dimensional C/SiC composites

Uniaxial compression tests for two-and-a-half-dimensional carbon fiber-reinforced silicon carbide composites along the warp and weft directions were conducted at room temperature. The results show that the stress-strain behaviors for both loading directions exhibited great anisotropy. The compressive strength was greater in the weft direction than in the warp direction, which is attributed to good confinement of the weft yarns and resisting roles of the warp yarns in the former. Microscopic examinations reveal that the fracture surfaces had good correlation with the weave architecture, and the failure mechanism was characterized by transverse shear resulting from fiber microbuckling in the axial yarns.