An unfired, refractory molded body (1), includes a binding agent matrix (2) containing at least one set, permanent binding material and aggregate grains (3) with and/or of biogenic silicic acid, preferably with and/or of rice husk ash, which grains are incorporated into the binding agent matrix (2), for thermal isolation of a molten metal, especially of molten steel, and/or of a metal ingot solidifying from the molten metal, and also the use of the molded body (1) for thermal isolation of a refractory lining, in particular in a multiple-layer brick wall or in a heat-treatment furnace, or as a corrosion barrier, e.g. against alkali attack, or as a fire protection lining or as filter material for hot gases.

The present invention provides a crucible for melting and casting a metal fuel, which includes a reaction preventing layer including: LaYO.sub.3; or ZrO.sub.2 containing a Y.sub.2O.sub.3 stabilizer at 5 to 10 wt %, and a method of melting and casting a metal fuel using the same.

Vessels selected from crucibles, pans, open cups and saggars essentially comprising of two components, from which (A) one component being a ceramic matrix composite, and (B) the second component being from metal or alloy, and wherein component (A) is the inner one.

A furnace includes a pedestal, a crucible, first and second heaters, and a controller. The crucible is arranged on a pedestal that is movable downwardly and is rotatable. The first and second heaters are spaced vertically along an outer wall of the crucible and are arranged around the crucible to heat pieces of solid material deposited in the crucible. A third heater is arranged above the crucible if the crucible includes a solid cylindrical mold or in a hollow cylindrical space of the crucible if the crucible includes a hollow cylindrical mold. The controller is configured to control the first and second heaters to heat the pieces of the solid material to form a melted liquid. The controller is configured to control the rotational and downward movements of the pedestal relative to the first and second heaters during solidification of the melted liquid to form an ingot.

High alumina cement is produced in a submerged combustion melter, cooled and ground.

High alumina cement is produced in a submerged combustion melter, cooled and ground.

High alumina cement is produced in a submerged combustion melter, cooled and ground.

A furnace includes a pedestal, a crucible, first and second heaters, and a controller. The crucible is arranged on a pedestal that is movable downwardly and is rotatable. The first and second heaters are spaced vertically along an outer wall of the crucible and are arranged around the crucible to heat pieces of solid material deposited in the crucible. A third heater is arranged above the crucible if the crucible includes a solid cylindrical mold or in a hollow cylindrical space of the crucible if the crucible includes a hollow cylindrical mold. The controller is configured to control the first and second heaters to heat the pieces of the solid material to form a melted liquid. The controller is configured to control the rotational and downward movements of the pedestal relative to the first and second heaters during solidification of the melted liquid to form an ingot.

A ceramic crucible having an Al.sub.2TiO.sub.5 body with face layers of non-reactive ceramic and a method of making the crucible. The ceramic crucible is made by utilizing a plaster mold and forming a crucible body as backing material in the plaster mold with a slurry. The slurry is fired to form the crucible body of aluminum titanate. Non-reactive ceramic slurry is applied to the interior of the crucible body to a predetermined thickness, wetting the crucible body and then fired forming a non-reactive layer as the interior surface of the ceramic crucible. The non-reactive layer forming the interior surface of the ceramic crucible is more dense than non-reactive layers in prior art crucibles. The dense non-reactive layer forms a stronger bond with the crucible body, reducing the potential for delamination of the non-reactive layer when a reactive alloy is melted in the crucible by vacuum induction melting.

An unfired, refractory molded body (1), includes a binding agent matrix (2) containing at least one set, permanent binding material and aggregate grains (3) with and/or of biogenic silicic acid, preferably with and/or of rice husk ash, which grains are incorporated into the binding agent matrix (2), for thermal isolation of a molten metal, especially of molten steel, and/or of a metal ingot solidifying from the molten metal, and also the use of the molded body (1) for thermal isolation of a refractory lining, in particular in a multiple-layer brick wall or in a heat-treatment furnace, or as a corrosion barrier, e.g. against alkali attack, or as a fire protection lining or as filter material for hot gases.