US Patent 7485278 Method for making silicon carbide whiskers

A ceramic composite made by compacting a starting powder blend. The composite includes between about 50 volume percent and about 99 volume percent of a ceramic matrix; and between about 1 volume percent and about 50 volume percent as-processed silicon carbide whiskers. The ceramic composite having a fracture toughness (KIC) of greater than about 4.0 MPam1/2. The ceramic has a silicon carbide whisker density as measured in whiskers per square millimeter equal to or less than about 1500 times the volume percent of silicon carbide whiskers, but in a density sufficient for the ceramic composite to have the fracture toughness.