The present invention provides silicon nitride with tungsten carbide
additives in a sinterable material comprising silicon nitride and
tungsten carbide, in which the silicon nitride content is a minimum of
about 80% and wherein the total nitride component is about 28-40 w/w %
N.sub.2, and further comprising about 1.5-3.5 w/w % Al, about 2-6 w/w %
Y, about 1.5-7 w/w % W, and about 3-9 w/w % O.sub.2. which after
sintering will produce ceramic bodies with a high degree of toughness
suitable for armor applications.