A method for producing a granular material from sintered magnesia by sintering of pressed articles, in particular pellets, from MgO powder, preferably from caustic MgO powder, and subsequent mechanical comminution of the pressed articles, the sintering being carried out in such a way that the granular material has a grain porosity (total porosity), according to DIN EN 993-1:1195-04 and DIN EN 993-18:1999-01, of from 15 to 38 vol %, preferably 20 to 38 vol %. Also, a batch for producing a coarse ceramic, refractory, shaped or unshaped product containing the porous sintered magnesia, to such a product produced from the batch and to a method for its production, to a lining, in particular a working casing and/or a backing, of a large-volume industrial furnace, the lining, in particular the working casing and/or the backing, having at least one such product, as well as to such an industrial furnace.

A porous refractory cast material contains a closed refractory aggregate fraction having a minimum particle size and a maximum particle size; the ratio of maximum particle size to minimum particle size is 10:1 or less. This closed refractory aggregate fraction comprises all of the porous refractory cast material having a particle diameter greater than 0.1 mm. The porous refractory cast material also contains a binder phase containing refractory selected from calcium aluminate cement, alumina phosphate, hydratable alumina, colloidal silica and combinations thereof. Also disclosed is a metallurgical vessel with an interior lining incorporating the porous refractory cast material.

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

The invention relates to a refractory ceramic batch for the production of an unformed refractory ceramic batch, the use of a batch of this kind for lining metallurgical melting vessels and also a metallurgical melting vessel which is lined with an unformed refractory ceramic product based on a batch of this kind.

Exemplary embodiments relate to a batch for producing an unshaped refractory ceramic product, to a method for producing a fired refractory ceramic product, to a fired refractory ceramic product and to the use of an unshaped refractory ceramic product.

A batch made of refractory mineral materials for lining of assemblies used for nonferrous metal melts, contains over 90% by weight of a mixture of the following constituents:from 3 to 74% by weight of at least one coarse-grain raw olivine material with at least 70% by weight forsterite content and having grain sizes of 50% by weight over 0.1 mmfrom 25 to 49% by weight of at least one ground magnesia with grain sizes of 50% by weight?1 mmfrom 0.9 to 14% by weight of at least one ground silicon carbide (SiC) with grain sizes of 50% by weight?1 mmfrom 0.1 to 10% by weight of at least one fine-particle dry pulverulent silica with particle sizes?500 ?mfrom 0 to 4% by weight of at least one antioxidant known per se for refractory productsfrom 0 to 4% by weight of at least one additional granulated refractory raw material known per se, more particularly having grain sizes of 50% by weight, in particular of 80% by weight, preferably of 100% by weight over 0.1 mmfrom 0 to 2% by weight of at least one additive known per se for the production of refractory products from batchesfrom 0 to 4% by weight of at least one additional substance known per se made of ground refractory materials and/or in the form of what is known as medium-grain-size material and/or of what is known as coarse-grain-size materialfrom 0 to 10% by weight of at least one binder known per se for refractory materials, e.g. in dry form or in ancillary packaging in liquid form.

A method for forming a refractory component of foundry system includes forming a preform from a refractory mixture. The refractory mixture includes a silicon carbide preceramic polymer and at least one of a refractory powder or refractory aggregate. The method further includes heating the preform to pyrolyze the silicon carbide preceramic polymer and form a refractory material defining the refractory component. The resulting refractory material includes at least one of the refractory powder or the refractory aggregate in a silicon carbide matrix. The refractory component defines an oxidation-resistant surface configured to contact molten metal.

The invention relates to a batch for producing an unshaped refractory ceramic product, to a method for producing a fired refractory ceramic product, to a fired refractory ceramic product and to the use of an unshaped refractory ceramic product.

The invention relates to a fire-resistant ceramic product.

The invention relates to a refractory ceramic batch for the production of an unformed refractory ceramic batch, the use of a batch of this kind for lining metallurgical melting vessels and also a metallurgical melting vessel which is lined with an unformed refractory ceramic product based on a batch of this kind.