US Patent 7550401 Method of making lightweight high performance ceramic material

A method of making a sintered ceramic composition includes the steps of: providing a powder that includes at least 50 wt. % boron carbide and 0.05 wt. % to 30 wt. % of at least one oxide selected from oxides of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy Ho, Er, Tm, Yb, and Lu; milling the powder to form a milled powder; drying the milled powder to form a milled, dried powder; and consolidating the milled, dried powder at a temperature in the range of 1500° C. to 2200° C. to form a sintered ceramic composition having a density of at least 90% of theoretical density, the sintered ceramic composition including zirconium diboride in an amount in the range of 1 wt. % to 10 wt. %.