Abstract: The invention relates to a method for forming a silicate coating on particles and to the particles thus obtained, characterized in that a solution containing silicate is added to a dispersion of uncoated particles having a diameter of less than 50 ?m and acoustic excitation occurs.

Abstract: A ceramic heating element arrangement in which a ceramic heating element made of SiC having electrical NTC (negative temperature coefficient) properties is provided for a circuit. At least one segment is provided in the circuit, whose resistance saturates at least quasi-asymptotically at the current flow required for a desired heat development.

Abstract: The invention relates to a conductive infrared-absorbing coating material consisting of indium tin oxide. According to the invention, said coating material has a yellow index of above 15.

Abstract: Homogeneous multicomponent dispersions in which at least two types of finely divided particles, having particle sizes differing by at least a factor of three between two of the types, are dispersed in a medium, are prepared by a process including:

Abstract: A process for producing a composite, containing at least one shrinkage-matched ceramic layer, wherein a starting material for the ceramic layer(s) has shrinkage behavior on sintering which is matched to remaining layer(s), and which is selected such that the ceramic-forming constituent of the same contains at least one ceramic powder of a specific size, and which process entails joining the layers of the composite by sintering.

Abstract: A process is described for producing a conductive sintered body based on silicon carbide, in which a) silicon carbide particles, optionally pretreated with a surface modifier, are dispersed in an aqueous and/or organic medium and positive or negative surface charges are generated on the silicon carbide particles by adjustment of the pH of the dispersion obtained; b) carbon black and boron carbide are mixed in as sintering aids, where at least the carbon black particles have a surface charge opposite to the surface charge of the silicon carbide particles and the boron carbide can also be added, completely or in part, at a later point in time (stage c′)); c) the slip thus obtained is shaped directly to form a green body or c′) a sinterable powder is isolated from the slip obtained and is shaped to form a green body, where the above boron carbide can also be added to this sinterable powder; and d) the green body obtained is subjected to pressureless sintering to form a sintered body in essential

Abstract: A process for preparing an agglomerate-free suspension of nanosize iron-containing oxide particles coated in a stable manner comprises preparing an aqueous suspension of nanosize iron-containing oxide particles which are partially or completely in the form of agglomerates; adding a trialkoxysilane and a water-miscible polar organic solvent which has a boiling point at least 10° C. higher than the boiling point of water; treating the resulting suspension with ultrasound until at least 70% of the particles present are in the range of ±20% of the average particle diameter; removing the water by distillation under the action of ultrasound; and separating the non-disintegrated agglomerates.

Abstract: The invention essentially relates to the use of ceramic powders whose surface has been rendered hydrophobic to produce fine-particle dispersions having a high solids content and a low viscosity. The invention further relates to specific ceramic powders whose surface has been rendered hydrophobic, and methods of producing them. Ceramic powders whose oxidic surface has hydroxide groups possessing a basic or amphoteric character can be rendered hydrophobic, for example, through the effect of a hydrophobic carboxylic acid. Acidic oxides are rendered hydrophobic through treatment with metal-containing hydrophobing agents which are, however, also suitable for rendering ceramic powders hydrophobic that have a basic or amphoteric character.