A composition which can be photopolymerized to make a part consisting of an oxide ceramic, or a hybrid part comprising at least one oxide ceramic and organic constituents, by a stereolithographic technique, the composition comprising: at least one photopolymerizable organic compound; at least one photo-initiator; at least one precursor of the oxide ceramic wherein the composition comprises from 25% to 70% by mass, relative to the total mass of the composition, of the at least one precursor of the oxide ceramic; and wherein the at least one precursor of the oxide ceramic comprises a mixture comprising a nanometric powder of the oxide ceramic, and at least one other element selected from a micrometric powder of the oxide ceramic and a pre-ceramic compound of the oxide ceramic.

An object of the present invention is to provide a high-density Cr—Si—C-based sintered body including chromium (Cr), silicon (Si) and carbon (C) and is furthermore to provide at least one of the high-density Cr—Si—C-based sintered body, a sputtering target including the sintered body or a method for producing a film using the sputtering target. The present invention can provide a Cr—Si—C-based sintered body including chromium (Cr), silicon (Si) and carbon (C), wherein the sintered body has a relative density of 90% or more and a porosity of 13% or less.

A cubic boron nitride sintered material comprises 30% by volume or more and 99.9% by volume or less of cubic boron nitride grains and 0.1% by volume or more and 70% by volume or less of a binder phase, the cubic boron nitride grain having a carbon content of 0.08% by mass or less, the cubic boron nitride sintered material being free of free carbon.

A process for the manufacture of a refractory block including more than 80% zirconia, in percentage by weight based on the oxides. The process includes the following successive stages: melting, under reducing conditions, of a charge including more than 50% zircon, in percentage by weight, such as to reduce the zircon and obtain a molten material, application of oxidizing conditions to the molten material, casting of the molten material, and cooling until at least partial solidification of the molten material in the form of a block. Also, the process can include heat treatment of the block.

New copper-coated titanium diboride electrodes are disclosed. The copper-coated titanium diboride electrodes may be used in an aluminum electrolysis cell. In one embodiment, a method includes installing the copper-coated titanium diboride electrode in the aluminum electrolysis cell and operating the aluminum electrolysis cell. During start-up, the aluminum electrolysis cell may be preheated and a bath may be formed from a molten electrolyte. Alumina (Al.sub.2O.sub.3) may in the added to the bath and reduced to aluminum metal. At least some of the copper film of the copper-coated titanium diboride electrode may be replaced by an aluminum film, thereby forming an aluminum-wetted titanium diboride electrode.

Organosilicon chemistry, polymer derived ceramic materials, and methods. Such materials and methods for making polysilocarb (SiOC) and Silicon Carbide (SiC) materials having 3-nines, 4-nines, 6-nines and greater purity. Processes and articles utilizing such high purity SiOC and SiC.

A method for manufacturing a part made of composite material includes forming a ceramic matrix phase in pores of a fibrous preform by pyrolysis of a cross-linked copolymer ceramic precursor, the cross-linked copolymer including a first precursor macromolecular chain of a first ceramic having free carbon, and a second precursor macromolecular chain of a second ceramic having free silicon, the first macromolecular chain being bonded to the second macromolecular chain by cross-linking bridges including a bonding structure of formula *.sup.1—X—*.sup.2; in this formula, X designates boron or aluminium, -*.sup.1 designates the bond to the first macromolecular chain and -*.sup.2 the bond to the second macromolecular chain.

A particulate mixture, suitable for use in ceramic article production, wherein the mixture includes from 30 wt % to 80 wt % recycled aluminium silicate material. The particulate mixture has a particle size distribution such that: (i) the d.sub.50 particle size is from 10 μm to 30 μm; (ii) the d.sub.70 particle size is less than 40 μm; and (iii) the d.sub.98 particle size is less than 60 μm.

A process for the production of a ceramic article includes the steps of: (a) preparing a particulate mixture; (b) contacting the particulate mixture to water to form a humidified mixture; (c) pressing the humidified mixture to form a green article; (d) optionally, subjecting the green article to an initial drying step; (e) optionally, glazing the green article to form a glazed green article; (f) subjecting the green article to a heat treatment step to form a hot fused article; and (g) cooling the hot fused article to form a glazed ceramic article. The particulate mixture includes from 30 wt % to 80 wt % recycled aluminium silicate material. The particulate mixture has: (i) a d.sub.50 particle size from 10 μm to 30 μm; (ii) a d.sub.70 particle size of less than 40 μm; and (iii) a d.sub.98 particle size of less than 60 μm. Steps (c) and (f), and optionally steps (d) and (e) are continuous process steps.

A recycled aluminium silicate material, suitable for use in ceramic article production, wherein the recycled aluminium silicate material has a particle size distribution such that: (i) the d.sub.50 particle size is from 10 μm to 30 μm; (ii) the d.sub.70 particle size is less than 40 μm; and (iii) the d.sub.98 particle size is less than 60 μm. A particulate mixture, suitable for use in ceramic article production, includes the above defined recycled aluminium silicate material.