A metal matrix composite comprises and/or consists of a uniform distribution of calcined ceramic particles having an average particle size of between 0.30 and 0.900 microns and a metal or alloy uniformly distributed with the ceramic particles and wherein the ceramic particles include oxides of two separate metals selected from the group consisting of Al, Li, Be, Pb, Fe, Ag, Au, Sn, Mg, Ti, Cu, and Zn, and in which said ceramic particles comprise at least 15 volume percent of the metal matrix sintered together and wherein said metal-matrix being machinable with a high speed steel (HSS) bit for greater than about one minute without excessive wear to the bit.

A method for treating refractory ceramic products is described herein. The method includes providing a refractory ceramic product, comprising magnesia and at least one of the following salts: one or more alkali salts and one or more alkaline earth salts. The method also includes providing a water-based liquid, combining the refractory ceramic product with the liquid, and separating the refractory ceramic product and the liquid.

A method for treating refractory ceramic products is described herein. The method includes providing a refractory ceramic product, comprising magnesia and at least one of the following salts: one or more alkali salts and one or more alkaline earth salts. The method also includes providing a water-based liquid, combining the refractory ceramic product with the liquid, and separating the refractory ceramic product and the liquid.

The invention relates to a batch composition for producing a refractory product, a method for producing a refractory product, a refractory product, and to the use of a synthetic raw material.

A glass furnace including an additive-containing product including an additive selected from: phosphorus compounds other than glasses and vitroceramics, tungsten compounds other than glasses and vitroceramics, molybdenum compounds other than glasses and vitroceramics, iron in the form of metal, aluminum in the form of metal, silicon in the form of metal, and their mixtures, silicon carbide, boron carbide, silicon nitride, boron nitride, glasses including elemental phosphorus and/or iron and/or tungsten and/or molybdenum, vitroceramics including elemental phosphorus and/or iron and/or tungsten and/or molybdenum, and their mixtures, and having the following chemical analysis, exclusively of the additive, as a percentage by weight on the basis of the oxides: Cr.sub.2O.sub.3?2%, and Cr.sub.2O.sub.3+Al.sub.2O.sub.3+CaO+ZrO.sub.2+MgO+Fe.sub.2O.sub.3+SiO.sub.2+TiO.sub.2?90%, and Cr.sub.2O.sub.3+Al.sub.2O.sub.3+MgO?60%, the content by weight of additive being in the range 0.01% to 6%.

A glass furnace including an additive-containing product including an additive selected from: phosphorus compounds other than glasses and vitroceramics, tungsten compounds other than glasses and vitroceramics, molybdenum compounds other than glasses and vitroceramics, iron in the form of metal, aluminum in the form of metal, silicon in the form of metal, and their mixtures, silicon carbide, boron carbide, silicon nitride, boron nitride, glasses including elemental phosphorus and/or iron and/or tungsten and/or molybdenum, vitroceramics including elemental phosphorus and/or iron and/or tungsten and/or molybdenum, and their mixtures, and having the following chemical analysis, exclusively of the additive, as a percentage by weight on the basis of the oxides: Cr.sub.2O.sub.3?2%, and Cr.sub.2O.sub.3+Al.sub.2O.sub.3+CaO+ZrO.sub.2+MgO+Fe.sub.2O.sub.3+SiO.sub.2+TiO.sub.2?90%, and Cr.sub.2O.sub.3+Al.sub.2O.sub.3+MgO?60%, the content by weight of additive being in the range 0.01% to 6%.

A metal matrix composite comprises and/or consists of a uniform distribution of calcined ceramic particles having an average particle size of between 0.30 and 0.900 microns and a metal or alloy uniformly distributed with the ceramic particles and wherein the ceramic particles include oxides of two separate metals selected from the group consisting of Al, Li, Be, Pb, Fe, Ag, Au, Sn, Mg, Ti, Cu, and Zn, and in which said ceramic particles comprise at least 15 volume percent of the metal matrix sintered together and wherein said metal-matrix being machinable with a high speed steel (HSS) bit for greater than about one minute without excessive wear to the bit.

A metal matrix composite comprises and/or consists of a uniform distribution of calcined ceramic particles having an average particle size of between 0.30 and 0.900 microns and a metal or alloy uniformly distributed with the ceramic particles and wherein the ceramic particles include oxides of two separate metals selected from the group consisting of Al, Li, Be, Pb, Fe, Ag, Au, Sn, Mg, Ti, Cu, and Zn, and in which said ceramic particles comprise at least 15 volume percent of the metal matrix sintered together and wherein said metal-matrix being machinable with a high speed steel (HSS) bit for greater than about one minute without excessive wear to the bit.

A sintered refractory product having a granulate bonded by a matrix and comprising, in percentages by mass based on the oxides, more than 40% chromium oxide Cr.sub.2O.sub.3, less than 50% aluminium oxide Al.sub.2O.sub.3, 1% or more zirconium oxide ZrO.sub.2, of which at least 20% by mass is stabilised in the cubic and/or quadratic form, 0.1% or more yttrium oxide Y.sub.2O.sub.3, acting as a stabiliser for the zirconium oxide ZrO.sub.2, less than 1.9% hafnium oxide HfO.sub.2, the total content of chromium, aluminium and zirconium oxides Cr.sub.2O.sub.2+Al.sub.2O.sub.3+ZrO.sub.2 being greater than 70%.

A sintered refractory product having a granulate bonded by a matrix and comprising, in percentages by mass based on the oxides, more than 40% chromium oxide Cr.sub.2O.sub.3, less than 50% aluminium oxide Al.sub.2O.sub.3, 1% or more zirconium oxide ZrO.sub.2, of which at least 20% by mass is stabilised in the cubic and/or quadratic form, 0.1% or more yttrium oxide Y.sub.2O.sub.3, acting as a stabiliser for the zirconium oxide ZrO.sub.2, less than 1.9% hafnium oxide HfO.sub.2, the total content of chromium, aluminium and zirconium oxides Cr.sub.2O.sub.2+Al.sub.2O.sub.3+ZrO.sub.2 being greater than 70%.