Abstract: Method of producing sand-blasting abrasive materials, and the materials so produced, consisting of silica sand and/or slag, coated with a thermosetting resin by heat treatment, and the coating being then rendered unsoluble and unmeltable, by subsequent, separate heat treatment. The resin may contain a catalyst.
Abstract: An apparatus is disclosed for producing solid materials in form of microspheres or spherules for a number of applications, such as nuclear fuel, catalyst, fluid beds for fluidization and other like applications. An inert gas shield is provided to surround the droplets of liquid from which the microspheres shall be originated so as to prevent a premature reaction of such droplets with the reaction gas. Provision is made for renewing the braking foam placed over the liquid reactive bath and the reactive gas is supplied in the form of a blade-like stream so as to improve the contact time and intensity between the droplets and the reactive gas.
April 11, 1978
Date of Patent:
August 25, 1981
AGIP NUCLEARE S.p.A.
Giovanni Bezzi, Ego Pauluzzi, Mauro Zanardi
Abstract: A mixture of oxides or salts of barium, titanium and tin (principal materials) are initially ground with two different classes of dopants. The first class consists of oxides or salts of rare earths or of elements such as antimony. The second class consists of oxides or salts of elements such as manganese or copper. After calcining and sintering, cooling of the ceramic body is obtained by adjusting to a very low rate (negative gradient of 10 to 30.degree. C. per hour) in a pure oxygen atmosphere.The material is primarily suited for use in capacitors having one or a number of layers which may be separated by electrodes inserted prior to sintering. The material has high apparent permittivity and can be employed at much higher voltages than in barrier-layer capacitors.
Abstract: A process for grinding coal or ores containing metal values comprising carrying out said grinding in a liquid medium and with a grinding aid comprising an anionic polyelectrolyte dispersible in the liquid medium and having a hydrocarbon backbone and a plurality of pendant anionic groups, said grinding aid being present in an amount effective to provide increased grinding efficiency.
Abstract: Technique for making exhaust muffler lining comprising mineral fibers with metal fibers distributed therein toward the inner surface of the lining, the metal fibers being bound by the fiber binder carried by the mineral fibers.
October 18, 1978
Date of Patent:
May 26, 1981
Rolf Sommer, Gustav Schweinfurth, Heinz-Jurgen Ungerer
Abstract: A production line for the manufacture of (unreinforced, reinforced or prestressed) concrete comprising concrete casting means, a circuit for hardening it and means for removing the hardened elements. It includes a chain of floats adapted to be moved in a moat of liquid and means for placing the concrete elements which have just been cast, on said floats, which by moving in the moat, transport the concrete elements through the hardening circuit, means being provided to bring back the floats to the concrete casting means. The installation is applied in the manufacture of piles, posts for electric cables, slabs, beams, panels and curbs.
Abstract: In one embodiment, a compact for tools, such as cutting, drilling, wire drawing and shaping tools, consists essentially of a porous mass of self-bonded, boron-doped diamond particles and a catalyst-solvent material. The method for making such a compact comprises the steps of bonding a mass of boron-doped diamond particles, aided by a catalyst-solvent material, under high temperatures and high pressures (HP/HT).In another embodiment, a composite compact, which is made in a similar manner to the first embodiment, consists essentially of (i) a layer of a porous mass of self-bonded, boron-doped diamond particles and catalyst-solvent material; and (ii) a substrate layer of cemented carbide bonded to the diamond layer.
Abstract: In fabricating sheet material with closely spaced parallel ribs on one side, a mold with ribbed shaped grooves is uniformly filled with a loose, dry molding material using a coater with a plurality of adjacent blades extending therefrom with the blade tips parallel to and preferably in contact with the mold top surface. The coater is swept across the mold top surface and the blades distribute and compress the molding material into the mold grooves. The invention is particularly useful for molding materials with high fiber content which are difficult to pack uniformly and with sufficient density into the mold.
Abstract: Method and apparatus for producing silicon nitride molded bodies by means of a pseudoisostatic hot pressing process. Silicon nitride is initially ground in a grinding vessel with grinding elements wherein the vessel is lined with the same material from which the grinding elements are made, e.g., hot pressed silicon nitride. Grinding is continued until a specific surface area greater than 15 m.sup.2 is obtained. The grinding takes place in the presence of a grinding liquid to prevent oxidation of the freshly ground silicon nitride. The silicon nitride suspension is then treated in a pressure vessel to remove the grinding liquid therefrom and form a blank. The blank is thereafter embedded within a pressure transfer medium, e.g., boron nitride, and inserted into the die of a hot pressing furnace to obtain the desired hot pressed silicon nitride.
Abstract: An abrasive sheet is disclosed which can be hand held or used with known abrasive devices, has longer abrasive life than existing abrasive sheets and has a novel attachment arrangement onto an abrasive support member. The abrasive sheet has abrasive material coated on one surface and a layer of resilient open-celled flexible foam on the other surface. The abrasive sheet may be used with a support member having a support surface with a multitude of fastening protuberances projecting from the support surface. The abrasive sheet is detachably fastened to the support member by pressing the layer of resilient open-celled foam against the support surface to have the protuberances enter and grip the open-celled foam.
Abstract: A method of sintering a shaped green, beta-type alumina body comprising: (A) inserting said body into an open chamber prepared by exposing the interior surface of a container consisting essentially of at least about 50 weight percent of alpha-alumina and a remainder of other refractory material to a sodium oxide or sodium oxide producing environment; (B) sealing the chamber; and heating the chamber with the shaped body encapsulated therein to a temperature and for a time necessary to sinter said body to the desired density. The encapsulation chamber prepared as described above is also claimed.
October 27, 1978
Date of Patent:
April 21, 1981
The United States of America as represented by the United States Department of Energy
Abstract: In grinding disks, toxic lead chloride and antimony sulfide may be replaced by non-toxic alkali metal chloroferrates (II,III) produced by melting together alkali metal chloride, anhydrous ferric chloride and iron powder.
Abstract: Plastically formable material, which may be formed under pressure into desired shapes, is fed while in a fluid or plastically formable condition to a pair of cooperating surfaces which are relatively movable into compressive relationship with material disposed therebetween. The face of at least one of such surfaces is patterned with a plurality of juxtapositioned geometrical impressions of desired size and shape so as to form a ribbon or sheet of uniformly sized and shaped particles from the plastically formable material supplied to the cooperating surfaces. The uniform particles are initially joined together by thin web or edge portions which maintain the continuity of the newly formed particles within a sheet form.
Abstract: An improvement for making polycrystalline compacts containing single crystal diamonds embedded therein is disclosed. Cracking of such compacts is minimized by isolating the diamond in a relatively compressible matrix before exposing the sample to high pressure-high temperature sintering conditions. This may be done, for example, by mixing the diamond crystals with graphite or amorphous carbon powder. Useful devices which can be made from such compacts are cutting tools and wire drawing dies.A sectional view of a wire die blank of this invention is depicted in FIG. 3. One single crystal diamond 12 is embedded in polycrystalline diamond matrix 14 which has been sintered within cemented tungsten carbide ring 16. The wire is drawn through aperture 18. It is felt that this type of die would improve the wire finish while helping to prevent the failure of the single crystal through cleavage. It is useful in drawing wires made of such materials as tungsten, copper coated steel, copper and nickel.
Abstract: A composition for polishing silicon and germanium comprises a synthetic amorphous silica polishing agent and a suspending agent selected from the group consisting of water-soluble carboxypolymethylene gums and xanthum gums. The composition may be used for polishing in the form of an aqueous alkaline slurry.
Abstract: An improved method for manufacturing spectacle lenses and the like from diglycol allyl carbonate or equivalent plastic by first heating the plastic monomer in the liquid state and containing a polymerization initiator therefor in a planar mold until a degree of polymerization in the range of about 65-85% of completion has been achieved, then removing the partially polymerized material from the mold, subjecting the same to deflection to a curvature corresponding to the desired lens and heating the thus-deflected material until polymerization is complete. Preferably, the initial planar molding step is carried out with a layer or sheet of the material of sufficient size as to contain a plurality of individual lens elements, and after removal thereof from the mold, a plurality of individual lens elements is derived therefrom and such elements are separately subjected to deflection and further polymerization. Preferably, the amount of polymerization initiator exceeds the normally used amount.
Abstract: A method of manufacturing reinforced elements includes the steps of providing a lattice-like mesh of threads lying in a first plane, applying a plurality of reinforcing fibers so that they extend in planes located at angles to the first plane in which the mesh of threads lies, and embedding the lattice-like mesh with the thus-applied fibers into a bulk of cement. A reinforced concrete element includes a bulk of cement and a reinforcing structure comprising a lattice-like mesh of threads and a plurality of fibers located in planes which are inclined to the plane of the mesh. The reinforcing fibers may extend normal or be inclined to the plane of the mesh of threads. They may be prefixed to the same before the embedding step.
Abstract: A flexible abrasive member is formed by applying a layer of metal (13;15,16) to mesh material (12). Abrasive material (14) is embedded in the metal layer during the deposition of the layer by an electrodeposition process. The mesh material may be electrically non-conducting woven material and the metal layer is deposited through the mesh material.In making the member the mesh material is laid on a smooth, preferably curvilinear, surface (10) formed with areas (11) for receiving the metal layer. Abrasive material is introduced onto the surface at the beginning of the metal deposition process or towards the end of the deposition process.
Abstract: Apparatus for fabricating a prefinished wallboard wherein a layer of settable material is applied to one side of a wall panel and a decorative pattern is formed in relief in the settable material which, when set, is harder than the wall panel. A decorative coating may be applied to the relieved portions of the moldable material, and reinforcing and insulating members may be connected to the opposite side of the panel.
February 9, 1979
Date of Patent:
March 17, 1981
Servando G. Hinojosa, Octavio G. Hinojosa