Combination of gel-casting and reactive melt infiltration for rapid fabrication of SiCw/SiC composites

Abstract

Gel-casting combined with reactive melt infiltration (RMI) process was first proposed for the rapid preparation of SiC whisker-reinforced SiC ceramic matrix composites (SiCw/SiC). Gel-casting process can prepare isotropic whisker preforms with high volume fraction (≥40 vol.%) in near-net-size shape. RMI process can densify the whisker preform rapidly and achieve a high density. The influence of resin carbon (as the carbon source of SiC matrix) content on the microstructural evolution, phase composition and mechanical properties of SiCw/SiC composites was studied in detail. When the resin carbon content is 24 vol.%, SiCw/SiC can obtain good mechanical properties (218 MPa of flexural strength and 3.11 MPa·m1/2 of fracture toughness) with high density (2.9 g·cm−3) and low open porosity (~0.36 vol.%).