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.

Disclosed is a hydraulically and chemically bonding refractory cement, which includes a caustic magnesia component having a BET specific surface area of at least 0.5 m.sup.2/g, and a carboxylic acid component, wherein the carboxylic acid component consists of at least one carboxylic acid that is only slightly water soluble and/or has a low dissolution rate in aqueous solutions, and which carboxylic acid component is capable of generating at least one soluble magnesium salt upon contact of the cement with water. Also disclosed is a corresponding refractory material containing the magnesia cement and to uses thereof for the manufacture of products useful in various industries.

Disclosed is a hydraulically and chemically bonding refractory cement, which includes a caustic magnesia component having a BET specific surface area of at least 0.5 m.sup.2/g, and a carboxylic acid component, wherein the carboxylic acid component consists of at least one carboxylic acid that is only slightly water soluble and/or has a low dissolution rate in aqueous solutions, and which carboxylic acid component is capable of generating at least one soluble magnesium salt upon contact of the cement with water. Also disclosed is a corresponding refractory material containing the magnesia cement and to uses thereof for the manufacture of products useful in various industries.

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.

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.

Disclosed is a refractory product for casting of steel, which is capable of forming a dense surface layer which is high in terms of a slag infiltration suppressing ability and strong, in a surface region thereof efficiently or sufficiently or in an optimum state. The refractory product contains 1 mass % or more of free carbon, and 2 mass % to 15 mass % of an aluminum component as metal, with the remainder comprising a refractory material as a main composition, wherein the refractory product has a permeability of 110.sup.16m.sup.2 to 1510.sup.16m.sup.2.

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 product, a batch composition for producing said product, a method for producing the product and the use of the refractory product.

A graphite-containing refractory has higher bending strength and fracture energy than known refractories. The graphite-containing refractory has a graphite content of 1% to 80% by mass. 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 m/fiber are bundled. The carbon fiber bundle has a length of 100 mm or more and is placed within the graphite-containing refractory to form the same.

The invention relates to a process for making a ceramic body that comprises providing particles of a metal salt precursor material wetted by a liquid medium. The particles are characterized by a grain size of below 600 nm, and the precursor material has a solubility in the liquid medium of at least 10.sup.5 mol/L. A pressure of 100 MPa is applied at a temperature of below 100 C., rendering a material of high theoretical density values previously unattainable at low temperatures. The invention further relates to a calcium carbonate ceramic material of the vaterite isomorph having a density of the material 1.76 g/cm3 and a Modulus of rupture 30 MPa, and to a calcium phosphate ceramic material consisting of the monetite isomorph with 2.5 g/cm3 density and a Modulus of rupture 18 MPa.