Effects of molding pressure on the microstructure and mechanical properties of 2D-Cf/SiC composites by PIP routes

Carbon fiber cloth reinforced silicon carbide (2D-C-f/SiC) composites were prepared through polycarbosilane(PCS)/divinylbenzene(DVB) pyrolysis with SiC as inactive filler. Effects of the molding pressure on the microstructure and mechanical properties of 2D-C-f/SiC composites were investigated. With increasing molding pressure from 0MPa to 3MPa, the fiber volume fraction of the composites was increased. As a result, the strengths of the composites were enhanced. But when the molding pressure exceeded 3MPa, SiC particles would damage the carbon fibers seriously. Therefore, although the fiber fraction of the composites was increased further, the flexural strengths of the composites were decreased. It was found that the composites fabricated with the molding pressure of 3 MPa exhibited highest flexural strength, reached 319.4 MPa.