Abstract: A novel curing process for preceramic organosilicon polymers is disclosed which involves contact with a gaseous hydrogen halide.

Abstract: A method for determining whether surface connected, through thickness defects exist in a coated carbon-carbon composite article. The method involves the immersion of the coated article in a low viscosity liquid; if a stream of bubbles rises from the surface of the coating, such bubbles indicate the existence of at least one surface connected, through thickness defect in the coating.

Abstract: Fibrous material is coated with boron nitride and a silicon-wettable material, the coated fibrous material is admixed with an infiltration-promoting material which is at least partly elemental carbon and the mixture is formed into a preform which is infiltrated with molten silicon producing a composite containing boron nitride coated fibrous material.

Abstract: A powder metallurgy produced high speed tool steel article comprising a mixture of prealloyed high speed tool steel particles coated with a hard, wear resistant material, such as a carbide or nitride, mixed with prealloyed high speed tool steel uncoated particles; the particles are compacted to essentially full density and the hard, wear resistant material is at the boundaries of the coated particles and contained in a continuous matrix of the high speed tool steel. The article is produced by hot compacting a particle charge to essentially full density of a mixture of the coated and uncoated particles.

Abstract: A stick of composite materials comprises a hot-pressed super-hard head member containing higher than 50 vol % of a diamond powder and/or a high pressure boron nitride powder, and a supporting member which is bonded at one of its ends with the hot-pressed super-hard head member. The stick of composite materials is characterized in that:the bonding between the head member and the supporting member is formed during the hot press process of the head member;the stick is of an elongated form, preferably of a cylindrical form of which the sectional diameter or equivalent sectional diameter is not larger than 3 mm;the length of the head member is 0.3 to 2.0 mm in the axial direction of the stick; and thatthe supporting member is more than five times longer in its axial direction than the head member.The stick of composite materials is usable as a blank for the microdrill, micropunch and the head of the dot character printer.

Abstract: This invention relates to substantially full-dense, near-net shape bodies made of dispersion strengthened copper (D.S.C.) powder and products which are cold formed and/or machined from these bodies, such as resistance welding electrodes. The invention includes processes for manufacturing substantially full-dense, near-net shape, substantially equiaxed bodies from D.S.C. powder.

Abstract: A method of manufacturing a scandate dispenser cathode having a matrix (1) at least the top layer of which consists substantially of a mixture of tungsten with scandium oxide or with a mixed oxide comprising scandium oxide. When sintering of the matrix is carried out at a temperature between 1300.degree. and 1700.degree. C., preferably at approximately 1500.degree. C. and in a hydrogen atmosphere, cathodes are obtained having a better recovery after ion bombardment compared with cathodes sintered at 1900.degree. C. Sintering in hydrogen results in a better reproducibility.

Abstract: Silicon carbide particles are produced by reacting a gaseous silicon compound or granular silicon with a carbon compound at a high temperature. In the reaction, the amount of free carbon content in the resultant silicon carbide particles can be controlled by monitoring the amount of unsaturated hydrocarbon such as acetylene, as a by-product. Moreover, silicon carbide particles can contain boron dispersed uniformly in the particles by a two step process comprising first reacting a silicon source and a boron source without a carbon source in a first reaction zone, to form boron-containing silicon particles, and second, reacting the resultant particles with a carbon source in a second reaction zone.

Abstract: A cavitation erosion resistant plain bearing comprising a steel backing, a sintered bronze interlayer and a lining of PTFE filled with 1 to 50% by volume of an ionic fluoride of low aqueous solubility.

Abstract: This disclosure discloses a method of making a niobium alloy having the general formula Nb.sub.y M where M is aluminum, gallium, indium, tin, germanium, silicon, or a mixture thereof. A niobium halide having the formula NbX.sub.y is reactive with M in a solution of a liquid alkali metal, where X is halogen and y is the valence of niobium. Also disclosed are spherical particles of the superconducting niobium alloy which are made by this method and a wire and magnet made from these particles.

Abstract: Superconductor wire, and methods of constructing same, including one or more filaments formed of submicron-particle superconductor powder each surrounded by an encapsulating sheath having a composite wall. The composite wall includes a ductile outer skin surrounding a relatively harder, higher yield strength inner wall portion. The harder, higher strength inner wall portion improves dimensional uniformity of the filaments as the wire is fabricated, with the potential for enhanced superconducting performance, while the ductile outer skin enhances metallurgical bonding between the outer skins of adjacent filaments, to ensure a homogenous, thermally conductive and normally electrically conductive matrix.

Abstract: A rare earth-iron permanent magnet is comprised of compacted Re-B-R type alloy particles in which R represents at least one element selected from rare earth elements and yttrium. The magnet has a sealing agent filling voids between the compacted Fe-B-R type alloy particles and a coating layer formed on outer surfaces thereof. The coating layer is formed by coating the surfaces wrought in a desired magnet shape.

Abstract: An iron-based anti-wear sintered alloy member containing at least 1.5 weight % C, 0.5 to 3.5 weight % P, and one or both of Mo and W in an amount of 0.5 to 3.0 weight % in terms of Mo (the conversion rate of W being 0.5) in addition to iron and having a phosphatic film formed at sliding contact portions. In addition to the above-described elements, one or both of Ni and Cu may be incorporated in an amount of 0.5 to 5.0 weight % in terms of Ni (the conversion rate of Cu being 0.5), of 0.3 to less than 8.0 weight % of Cr may be incorporated, or one or both of Ni and Cu may be incorporated in an amount of 0.3 to 0.7 weight % in terms of Ni together with 0.3 to 0.7 weight % of Cr.

Abstract: A nuclear power system comprises a plurality of modules disposed in below-grade pits to provide a compact, self-contained nuclear power supply. The modules are preferably individually transportable so that they may be substantially preassembled prior to installation. The system operates at relatively low temperatures and pressures, and includes various safety features which would prevent radioactive contamination of the surrounding environment in the event of a disturbance causing rupture of one or more of the odules or the pipes interconnecting the modules. The system also provides a low resistance flow path for vapor discharged from the turbine to improve efficiency.

Abstract: This case relates to tough, wear resistant graded structure composites, to a process for preparing the same and to tools and products fabricated therefrom. The composites have a surface layer e.g. of WC and a binder, an interface layer, e.g. which is a stepwise transition from the surface layer whereby the binder content thereof gradually increases, a substrate layer which is a combination of e.g. an initial high carbon steel layer and finally a base layer of bainitic steel. The composites are substantially non-porous and can be used to fabricate components such as drill bits, wear plates, pump components machine tools, seals, washers, bearings and the like.

Abstract: The present invention relates to an alloy for cutting tools comprising 75-97% by weight of a hard carbonitride component and 3-25% by weight of a binder metal, the hard component comprising titanium as the main metallic component besides tungsten, molybdenum, tantalum and optionally vanadium and as non metallic components carbon and nitrogen. The binder metal is selected from the group consisting of iron, cobalt and nickel.The plastic deformation resistance of the alloy has been improved by adding tantalum as a mixed carbide (Ti,Ta)C possibly also including Nb.

Abstract: A rapidly solidified magnesium based alloy contains finely dispersed magnesium intermetallic phases. The alloy has the form of a filament or a powder and is especially suited for consolidation into bulk shapes having superior combination of strength, ductility and corrosion resistance.

Abstract: The invention provides an aluminum base bearing alloy which is excellent in both lubricating capability and fatigue resistance and is useful, e.g. in automotive engines. The bearing alloy consists essentially of at least one lubricating element such as Pb and/or Sn the total amount of which is more than 0.04 and not more than 0.07 by sectional area ratio to the aluminum matrix, Si the amount of which is in the range from 0.01 to 0.17 by sectional area ratio to the aluminum matrix, 0.2-5.0 wt % of at least one reinforcing element such as Cu and/or Cr, 0-3.0 wt % of at least one refining element such as Ti and/or B and the balance of Al. The grain size of the lubricating element(s) is not larger than 8 .mu.m, and the grain size of Si is not larger than 12 .mu.m and preferably not smaller than 6 .mu.m.

Abstract: Method of manufacturing metal products from a powder (19) which is received in a mould cavity formed by a gas-tight casing (10, 11, 12, 13) and is isostatically hot pressed in the casing to form a monolithic body. A body (14) of graphite, hexagonal boron nitride, or another similar ceramic material is provided as a core in the mould cavity, and after the isostatic hot pressing this core is removed from the produced monolithic body by blasting.

Abstract: A multijunction solar cell is disclosed which uses a patterned intercell ohmic connection as the tunnel junction to connect a top solar cell in electrical and optical series with a bottom solar cell. By confining this patterned tunnel junction to shadowed areas directly beneath the top surface metallization grid, the tunnel junction is set free from the requirement that it be transparent and have band gaps greater than or equal to those of the top solar cell.