Abstract: Disclosed herein are prepregs for ceramic matrix composites, processes for the preparation of a green bodies using the prepregs disclosed herein, and processes for the preparation of the ceramic matrix composites from the green bodies prepared according processes provided herein.

Abstract: A prepreg for a ceramic matrix composite, a process for the preparation of a green body with the help of the prepreg, and a process for the preparation of the ceramic matrix composite from the green body prepared according to the present invention are provided. The inventive process comprises the following steps: a) impregnating an arrangement of ceramic fibers with a slurry, which slurry comprises the following components: (i) 10 to 40 vol.-%, based on the total volume of the slurry, of ceramic particles, (ii) an alcoholic organic solvent selected from: (ii-1) 21 to 35 wt.-%, based on the total weight of the ceramic particles in the slurry, of glycerol, (ii-2) 10 to 35 wt.-%, based on the total weight of the ceramic particles in the slurry, of an oligo or polyethylene glycol with an average molecular weight of at most 800 g/mol, (ii-3) 10 to 35 wt.-%, based on the total weight of the ceramic particles in the slurry, of at least one C2-C6 alkane diol, and (ii-4) 10 to 35 wt.

Abstract: The invention relates to a method for producing a composite body and to a composite body produced using the method, wherein the composite body (10) is formed as a pressure pipe or as a pressure container, wherein the composite body is composed of a main body (13) that is made of steel and of a coat (14) that is made of a fiber composite (15), said coat enclosing the outside of the main body at least in some sections, wherein, for forming the fiber composite, a fibrous material is wound around the main body, wherein the fibrous material is impregnated with a resin before or after winding, wherein the wound and impregnated fibrous material is heated in order to form the fiber composite, wherein the method is carried out in situ on a built-in pressure pipe or pressure container, wherein the wound and impregnated fibrous material is heated to up to 700° C.

Abstract: The invention relates to a method for producing a composite body and to a composite body produced using the method, wherein the composite body (10) is formed as a pressure pipe or as a pressure container, wherein the composite body is composed of a main body (13) that is made of steel and of a coat (14) that is made of a fibre composite (15), said coat enclosing the outside of the main body at least in some sections, wherein, for forming the fibre composite, a fibrous material is wound around the main body, wherein the fibrous material is impregnated with a resin before or after winding, wherein the wound and impregnated fibrous material is heated in order to form the fibre composite, wherein the method is carried out in situ on a built-in pressure pipe or pressure container, wherein the wound and impregnated fibrous material is heated to up to 700° C.

Abstract: In order to improve a method for the production of structural ceramics and/or functional ceramics consisting of silicon carbide ceramics, with which a porous precursor body is produced from a cellulose-containing material, the porous precursor body is converted into an open-pored carbon body by means of pyrolysis and the open-pored carbon body is converted into silicon-containing carbide ceramics, in particular, silicon carbide ceramics as a result of infiltration of silicon-containing materials, in such a manner that the structural ceramics and/or functional ceramics as well as the components produced therefrom can be produced with properties which are as reproducible as possible it is suggested that at least cellulose-containing powder be used as starting ingredient for the production of the precursor body.

Abstract: A piston-rod assembly with a piston rod having at least one attachment at one end. The piston rod is fabricated of fiber reinforced composite. The piston rod has a body of fiber-reinforced ceramic with a basic matrix of carbon fibers or ceramic fibers or both wherein at least silicon carbide is embedded and with an open porosity, at least at the surface layer, of no more than 3% of the volume of that layer admitting lubricants into the pores. The at least one attachment (2, 18a, 19, or 22) includes at least one component of a non-ceramic material that fits into and/or interlocks with the piston rod.

Abstract: In order to improve a method for the production of structural ceramics and/or functional ceramics consisting of silicon carbide ceramics, with which a porous precursor body is produced from a cellulose-containing material, the porous precursor body is converted into an open-pored carbon body by means of pyrolysis and the open-pored carbon body is converted into silicon-containing carbide ceramics, in particular, silicon carbide ceramics as a result of infiltration of silicon-containing materials, in such a manner that the structural ceramics and/or functional ceramics as well as the components produced therefrom can be produced with properties which are as reproducible as possible it is suggested that at least cellulose-containing powder be used as starting ingredient for the production of the precursor body.

Abstract: A calibrating consists at least in part of a carbon fiber composite body. The composite body is formed from a porous material from a carbon-containing matrix, into which carbon fibers are embedded, this matrix is thickened by fluid infiltration of Si, which is essentially converted by reaction with carbon to SiC. The overall portion of Si and SIC is a maximum of 60% by volume. The carbon fibers have a minimum length of 3 mm.

Abstract: A piston-rod assembly with a piston rod having at least one attachment at one end. The piston rod is fabricated of fiber reinforced composite. The piston rod has a body of fiber-reinforced ceramic with a basic matrix of carbon fibers or ceramic fibers or both wherein at least silicon carbide is embedded and with an open porosity, at least at the surface layer, of no more than 3% of the volume of that layer admitting lubricants into the pores. The at least one attachment (2, 18a, 19, or 22) includes at least one component of a non-ceramic material that fits into and/or interlocks with the piston rod.

Abstract: A friction element for use in a safety braking device for braking elevators co-operating with at least one elevator guide rail. The friction element has at least one friction surface that can be pressed against the guide rail to decelerate the elevator. The friction element is formed of a fiber-reinforced, ceramic composite material, containing silicon carbide and carbon with carbon fibers as reinforcing components. Preferably, the composite material is formed by a matrix of silicon carbide and carbon and the reinforcing component are exclusively carbon fibers with a minimum length of 10 mm and the volume content of carbon fibers in the friction element being between 30% and 70%.

Abstract: The invention relates to an optical system comprising at least one first and second optical element, whereby the optical elements are arranged at a predetermined distance from one another, using a mounting. The mounting comprises compensation elements for modifying the predetermined distance between a first optical element and a second optical element, according to the temperature. The optical system is a telescope and the distance between the primary mirror and the secondary mirror is modified according to the temperature.

Abstract: The present invention relates to a method for making a protective coating containing silicon carbide on at least a portion of the surface of a substrate made from a material with a softening temperature that is above the temperature applied to make the protective coating, where silicon is deposited on the portion of the surface of the substrate and where, under vacuum or in an inert atmosphere, the substrate is heated to a temperature above the melting point of silicon, and the silicon is brought to reaction with carbon that is contained in a porous coating. The surface of the object to be coated is initially provided with a porous carbon coating with an open porosity in a range between 40 and 95%, where said porous carbon coating is covered with a uniform coating of silicon, where the ratio in percent of mass (Ma-%) of the applied silicon to that of the carbon in the porous carbon coating is greater than 2.

Abstract: A friction element for use in a safety braking device for braking elevators co-operating with at least one elevator guide rail. The friction element has at least one friction surface that can be pressed against the guide rail to decelerate the elevator. The friction element is formed of a fiber-reinforced, ceramic composite material, containing silicon carbide and carbon with carbon fibers as reinforcing components. Preferably, the composite material is formed by a matrix of silicon carbide and carbon and the reinforcing component are exclusively carbon fibers with a minimum length of 10 mm and the volume content of carbon fibers in the friction element being between 30% and 70%.

Abstract: The present invention relates to a method for making a protective coating containing silicon carbide on at least a portion of the surface of a substrate made from a material with a softening temperature that is above the temperature applied to make the protective coating, where silicon is deposited on the portion of the surface of the substrate that is to be provided with a protective coating and where, under vacuum or in an inert atmosphere, the substrate is heated to a temperature above the melting point of silicon, is brought to reaction with carbon that is contained in a porous coating and is thereafter cooled down, wherein to achieve a homogeneous protective coating of silicon carbide and free silicon the part of the surface of the object to be coated is initially provided with a porous carbon coating with an open porosity in a range between 40 and 95%, where said porous carbon coating is covered with a uniform coating of silicon, where the ratio in percent of mass (Ma-%) of the applied silicon to that o

Abstract: In a brake disk for a vehicle disk brake, a material from the carbon group is used for an internally ventilated disk brake. The individual components, such as the friction rings and the ribs, are manufactured individually or partially together and can be fastened to one another by way of an unreleasable connection, such a high-temperature welding or gluing.

Abstract: A calibrating body consists at least in part of a carbon fiber composite body. The composite body is formed from a porous material from a carbon-containing matrix, into which carbon fibers are embedded, this matrix is thickened by fluid infiltration of Si, which is essentially converted by reaction with carbon to SiC. The overall portion of Si and SiC is a maximum of 60% by volume. The carbon fibers have a minimum length of 3 mm.

Abstract: A tool for machining workpieces, specially metal workpieces, by cutting, e.g., grinding, polishing, milling, separating or honing, comprising at least one stock-removing tool portion and whose machining range consists of a composite material containing a hard material. Said tool is characterized in that the composite material is formed by a fiber structure consisting of substantially continuous fibers made of carbon and/or a ceramic material and by a matrix containing carbon and hard material, and is also characterized in that at least the machining range, like the cutting or milling tool, is made of said composite material.

Abstract: The friction unit, in particular brake disc, has at least one friction face, with a friction element and with at least one molded unit, the friction element being made from carbon fiber-reinforced composite material and joined permanently to the molded unit. The friction unit is characterized in that the (minimum of one) molded unit (6, 13, 23, 23′) is joined to the friction element (5) in such a way that at least part of it forms a region of the friction surface (7) and the molded unit (6, 13, 23, 23′) has a higher thermal conductivity along the perpendiculars to the surfaces than the friction surface (7) itself.

Abstract: Disclosed is a method for manufacturing a friction element designed for frictional contact with a body and for use, in particular, in brakes or clutches. In the method, a porous carbon block, which approximately matches the shape of the end of the abrasion unit, is produced, liquid silicon is infiltrated into the pores of the carbon block, and the block is ceramized by initiating a chemical reaction to form silicon carbide. In order to further fashion a friction element of this kind to increase its resistance to thermal stresses and so that it is also easy to manufacture, the porous carbon block is shaped, before the silicon is infiltrated into it, in such a way that cavities and/or recesses are formed in certain internal and/or external zones for cooling and/or reinforcement purposes, the cavities and/or recesses retaining essentially the same shape and size after ceramization.

Abstract: Disclosed is a friction element designed for frictional contact with a body and for use, in particular, in brakes or clutches. The friction element has at least one freely accessible surface formed by a carbon-fiber-reinforced porous carbon block, at least some pores of which are filled with silicon and silicon carbide. In order to provide a friction element of this kind, as well as a method of manufacturing the friction element, which gives the advantages associated with C/C--SiC materials and which can be manufactured inexpensively, thus making it suitable, from the cost point of view, for general use particularly in the automobile-construction industry, the friction element is made up of at least one core element and at least one friction block securely bonded to it, the friction block being bonded to the core element on the side remote from its friction surface and the two elements being joined to each other by a high-temperature-resistant bonding layer.