An industrial furnace for melting materials is provided. The industrial furnace includes metal components, a refractory shell, and a fill. The refractory shell is positioned to cover an inner surface of the metal components such that one or more pockets are defined between the metal components and the refractory shell. The refractory shell has an inner surface that substantially defines a melting bath in which the materials are deposited for melting. The fill is disposed in each of the pockets. 90% to 99.5% of the fill is composed of one or more magnesia materials selected from the group consisting of dead-burned magnesia and fused magnesia.

A direct current plasma arc furnace includes a tank having a crucible delimiting a chamber to receive material to be melted and/or treated; refractory walls surrounding the crucible outer surface; a metallic frame covering the refractory walls; and a heating system for heating the received material. The heating system includes two electrodes acting as cathode and anode, respectively, wherein the first electrode is a movable electrode to project vertically into the chamber. The crucible is part of an anode system also having the second electrode and at least one part connecting the crucible and second electrode. The crucible receives and holds material to be melted and/or treated and provides electric conduction for the flow of current to heat the material, such that the voltage potential difference between the cathode and any point of the crucible surface defined to be in contact with the material is the same.

A crucible, an evaporation source and an evaporation device are disclosed. The crucible includes a crucible body. The crucible body includes: an inner heating layer with a first heater assembly and an outer heating layer with a second heater assembly. The outer heating layer is at a periphery of the inner heating layer, and surrounds the inner heating layer, and a space between the outer heating layer and the inner heating layer defines an accommodation space for a to-be-evaporated material.

The invention relates to an induction crucible furnace and to a magnetic return element for an induction crucible furnace. The induction crucible furnace has a corresponding coil and a plurality of magnetic return elements, which are designed in the form of individual units arranged on the outer lateral surface of the coil with peripheral spacing. In order to guide the magnetic flux produced by the coil, the magnetic return elements each have an assembly consisting of a plurality of elongate individual elements of magnetically permeable material that are electrically insulated from each other and extend parallel to the furnace axis. Said individual elements consist at least partially of bars, which are electrically insulated from each other and the longitudinal axes of which extend parallel to the furnace axis. In this way, both eddy currents that hit the assembly from the radial direction and eddy currents that hit the assembly with a transverse component are minimized.

Vessels such as crucibles, pans, open cups and saggars, containing a monolithic ceramic material, and a ceramic matrix composite, wherein the monolithic ceramic material is an inner part. A method for making oxide materials that can be utilized in the contact with corrosive materials and that allows for higher conversions in a given heating process.

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.

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.

Vessels such as crucibles, pans, open cups and saggars, containing a monolithic ceramic material, and a ceramic matrix composite, wherein the monolithic ceramic material is an inner tart. A method for making oxide materials that can be utilized in the contact with corrosive materials and that allows for higher conversions in a given heating process.