Patent ID: 8318622
Filing Date: 2012-11-27
Classification: C04B,F41H

Abstract:
1. A SiAlON armor ceramic made from a starting powder mixture including silicon nitride powder, the armor ceramic comprising: a ceramic body comprising between about 64 weight percent and about 90 weight percent alpha SiAlON phase that contains an alpha SiAlON-bound rare earth element wherein the alpha SiAlON-bound rare earth element is the sole rare earth element in the ceramic, and between about 5 weight percent and about 35 weight percent of a beta SiAlON phase of the formula Si the alpha SiAlON-bound rare earth element in the alpha SiAlON phase being present as a result of the starting powder mixture containing between about 1 weight percent and about 7 weight percent of an oxide of the alpha SiAlON-bound rare earth element; and the ceramic body having a fracture toughness (K