Abstract: This invention relates to a composition comprising: ceramic refractory particulates made from alumina, one or more rare earth oxides, one or more oxides of a transition metal, the transition metal being Sc, Zn, Ga, Y, Cd, In, Sn, Tl, or a mixture of two or more thereof; an alumina and phosphate containing composition; and water. The composition is free of SiO2 or substantially free of SiO2, and is useful as a mortar or coating for molten aluminum or steel contact refractories.
Abstract: The disclosed invention relates to a reinforced ceramic refractory made from an as-batched composition comprising alumina; a rare earth oxide; an oxide of a transition metal comprising Sc, Zn, Ga, Y, Cd, In, Sn, Tl or a mixture of two or more thereof; and chopped ceramic fibers containing nanofibrils; the refractory exhibiting a modulus of rupture measured at 2500° F. (1371° C.) of at least about 2500 psi, as determined by the test method ASTM C583. A process for making the reinforced ceramic refractory is disclosed.