Alumina-zirconia-silicon carbide-magnesia ceramic cutting tools

摘要

A metalcutting insert is provided with an alumina based ceramic composition composed of (in volume percent, v/o): about 1.5 to 37.5 silicon carbide whiskers; about 5 to 17.5 zirconia; residue of a magnesium oxide addition added in an amount effective to enhance the metalcutting lifetime of the cutting edge of the insert; and an alumina based matrix in which the silicon carbide whiskers, zirconia and residue of magnesium oxide are substantially homogeneously distributed. At least 2 v/o of the alumina based ceramic composition is tetragonal zirconia.