Improvements in Mechanical Properties in SiC by the Addition of TiC Particles

Silicon carbide ceramics containing up to 24.6 vol% dispersed TiC particles yielded fully dense composites by hot‐pressing at 2000°C with 1 wt% Al and 1 wt% C added. The micro‐structure consists of fine TiC particles in a fine‐grained SiC matrix. Addition of TiC particles increases the critical fracture toughness of SiC (to ∼6 MPa·m 1/2 at 24.6 vol% TiC) and yields high flexure strength (≥680 MPa), with both properties increasing with increasing volume fraction of TiC. The strengths at high temperatures are also improved by the TiC additions. Observations of the fracture path indicate that the improved toughness and strength are a result of crack deflection by the TiC particles.