A ceramic substrate and a method for production thereof are provided, in which the ceramic substrate includes a composite of : a first ceramic layer including Sr anorthite and Al.sub.2O.sub.3 or an oxide dielectric with a dielectric constant higher than that of Al.sub.2O.sub.3; and a second ceramic layer including Sr anorthite and cordierite and having a dielectric constant lower than that of the first ceramic layer.

A refractory, coarse ceramic product including at least one granular refractory material, has an open porosity of between 22 and 45 vol.-%, in particular of between 23 and 29 vol.-%, and a grain structure of the refractory material, wherein the medium grain size fraction with grain sizes of between 0.1 and 0.5 mm is 10 to 55 wt.-%, in particular 35 to 50 wt.-%, and wherein the remainder of the grain structure is a finest grain fraction with grain sizes of up to 0.1 mm and/or coarse-grain fraction with grain sizes of more than 0.5 mm.

An inorganic fiber containing silica, alumina, one or more alkali metal oxides, and one or more of alkaline earth metal oxides, transition metal oxides, or lanthanide series metal oxides. The inorganic fiber exhibits good thermal performance at use temperatures of 1260° C. and greater, retains mechanical integrity after exposure to the use temperatures, is free of crystalline silica upon devitrification, is alkali flux resistant, exhibits low bio-persistence in an acidic medium, and exhibits low dissolution in a neutral medium. Also provided are thermal insulation products incorporating the inorganic fibers, a method for preparing the inorganic fiber and a method of thermally insulating articles using thermal insulation prepared from the inorganic fibers.

A ceramic composition according to an embodiment of the present invention contains: a main phase component represented by CaMgSi.sub.2O.sub.6 or Ba.sub.4(Re.sub.(1-x), Bi.sub.x).sub.9.33Ti.sub.18O.sub.54; and an additive component containing a Li component and a B component, An observation field, a part of a sectional surface of the ceramic composition, is divided into a plurality of unit observation regions. Among all the unit observation regions, those containing no or little sintering agent component are referred to as the main crystal regions. An area percentage of main crystal regions relative to the observation field is 30% or more, the main crystal regions being the unit observation regions containing 0.5% or less by area of the additive component.

The present invention relates to a ceramic paste composition comprising a matrix and water, wherein the matrix comprises, based on the total weight of the matrix: about 98 wt % to about 100 wt % of minerals of which at least 30 wt % are phyllosilicates and less than about 2 wt % organic additive; and wherein water is present from about 18 wt % to about 28 wt % based on the total weight of the ceramic paste composition. The present invention also relates to a method of forming a 3D structure using the ceramic paste composition of the invention.

A batch mixture comprising pre-reacted pseudobrookite particles consisting essentially of aluminum titanate and magnesium dititanate, a reactive alumina source, a reactive titania source, and a reactive silica source. Other batch mixtures and methods of manufacturing honeycomb extrudates and porous honeycomb bodies using the batch mixture are disclosed.

A cordierite-containing ceramic body with % P≥50%, df≤0.50, and a combined weight percentage of crystalline phases containing cordierite and indialite of at least 85 wt %. The porous ceramic body contains, as expressed on a relative oxide weight percent basis in terms of MgO, Al.sub.2O.sub.3, and SiO.sub.2 that is within a field defined by (15.4, 34.1, and 50.5), (12.2, 34.1, and 53.7), (13.3, 31.2, and 55.5), and (16.6, 31.1, and 52.3). Batch composition mixtures and methods of manufacturing a porous ceramic body using the batch compositions are provided, as are other aspects.

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 base plate containing a having a top and a bottom and comprising a beryllium oxide composition containing at least 95 wt % beryllium oxide and optionally fluorine/fluoride ion. The base plate demonstrates a clamping pressure of at least 133 kPa at a temperature of at least 600° C. and a bulk resistivity greater than 1×10.sup.5 ohm-m at 800° C.

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.