Westinghouse Electric Corporation

Natraj C Iyer

Alan T Male

William R Lovic

Maurice G Fey

Graham A Whitlow

Sidney J Cherry

Walter J Carr, Jr

Paul E Denney

David J Boes

William F Hannan, Iii

Norman S Hoyer

Robert L Thomas

Eleanor Gettliffe

Allan J Bamford, Deceased

Elmer E Eiffler

Robert E Gainer

A composite brush to shunt attachment wherein a volatile component of a composite but mostly metallic brush, used for current collection purposes, does not upon welding or brazing, adversely affect the formation of the interfacial bond with a conductive shunt which carries the current from the zone of the brush. The brush to shunt attachment for a brush material of copper-graphite composite and a shunt of copper, or substituting silver for copper as an alternative, is made through a hot isostatic pressing (HIP). The HIP process includes applying high pressure and temperature simultaneously at the brush to shunt interface, after it has been isolated or canned in a metal casing in which the air adjacent to the interface has been evacuated and the interfacial area has been sealed before the application of pressure and temperature.

Shunt attachment and method for interfacing current collection systems

Copper-chromium contacts and copper-ferrous material shields are used in vacuum circuit interrupters. The copper chromium contacts include a specific copper-iron non-abutting section, and an abutting layer preferably of copper-chromium with a layer thickness that constitutes about 50% of the total thickness of the contact which constitutes the abutting section of the contact structure. The shield for the contacts, are preferably formed of copper-ferrous material and 'X' in which 1%-50% is ferrous material, and 'X'=chromium 0% to 30% and ferrous material plus 'X' is less than 60% of the total shield. The contacts and shields are formed by a powder metallurgical procedure.

Vacuum circuit interrupter contacts and shields

A ceramic-based coating is provided on a sealing surface of a sealing assembly component by processing and applying a powder mixture of ceramic particles and metal binder, encasing the coating of powder on the sealing surface by applying a metallic cover thereover, evacuating the atmosphere between the cover and coating, hot isostatic pressing the component and coating, cooling the component and coating, and after cooling thereof removing the cover from the coating. The powder processing includes mixing the ceramic particles and metal binder to produce a mixture, pretreating the mixture by heating it to the melting point of the metal binder which is less than the melting point of the ceramic particles to produce a mass of ceramic particles coated with molten metal binder and having a reduced gas content, cooling the mass of ceramic particles coated with molten metal binder to produce a solid mass thereof, and pulverizing the solid mass of metal binder coated-ceramic particles to granulate the powder mixture of ceramic particles to the desired size and still at least partially coated with metal binder. The resultant coating is densified substantially to its full theoretical density, metallurgically bonded to the substrate exterior surface, and has ceramic particles which are interparticle bonded together due to the processing step.

Method of forming a coating on a reactor coolant pump sealing surface

A superconductor is made, having a core (10) of superconducting material, enclosed by a contacting metallic sheath (12), where the sheath (12) contains a layer of Ag-Pd alloy with interdispersed, discrete particles of a metal selected from the group consisting of W, Mo, Ni and their mixtures.

High temperature superconductor having a high strength thermally matched

An annular chromium carbide coating on an annular sealing surface of a stainless steel sealing assembly component for use in a nuclear reactor coolant pump, is treated by encasing at least the chromium carbide coating on the stainless steel sealing surface by applying a metallic cover thereover, evacuating the atmosphere between the cover and the coating on the sealing surface, hot isostatic pressing the stainless steel sealing assembly component and the chromium carbide coating thereon encased by the cover, cooling the sealing assembly component and the coating thereon encased by the cover, and after cooling thereof removing the cover from the coating. The result is a chromium carbide coating on the sealing component substrate densified substantially to its full theoretical density (greater than 99%) and metallurgically bonded by the hot isostatic pressing to the substrate exterior surface.

Method of treating a coating on a reactor coolant pump sealing surface

High density compacts are made by providing a compactable particulate combination of Class 1 metals selected from at least one of Ag, Cu and Al, with material selected from at least one of CdO, SnO, SnO.sub.2, C, Co, Ni, Fe, Cr, Cr.sub.3 C.sub.2, Cr.sub.7 C.sub.3, W, WC, W.sub.2 C, WB, Mo, Mo.sub.2 C, MoB, Mo.sub.2 B, TiC, TiN, TiB.sub.2, Si, SiC, Si.sub.3 N.sub.4, usually by mixing powders of each, step (1); uniaxially pressing the powders to a density of from 60% to 95%, to provide a compact, step (2); hot densifying the compact at a pressure between 352 kg/cm.sup.2 (5,000 psi) and 3,172 kg/cm.sup.2 (45,000 psi) and at a temperature from 50.degree. C. to 100.degree. C. below the melting point or decomposition point of the lower melting component of the compact, to provide densification of the compact to over 97% of theoretical density; step (3); and cooling the compact, step (4).

Methods of making high performance compacts and products

A composite hyperconductor for use at cryogenic temperatures and particularly well suited for AC applications employs at least one filament of conductor having an extremely low electrical resistance at cryogenic temperatures, a strengthening matrix surrounding the conductor, and a barrier for electrically insulating the conductor from the matrix while providing for efficient heat transfer therebetween and/or serving as a diffusion barrier to prevent contamination of the high purity conductor during processing. The preferred composite hyperconductor for space applications comprises an ultra high purity aluminum conducting filament, a aluminum alloy matrix and a boron nitride barrier.

Cryogenic conductor

A process of hot pressing of materials to form articles or compacts is characterized by the steps: (A) providing a compactable particulate mixture; (B) uniaxially pressing the particles without heating to provide article or compact (22); (C) placing at least one article or compact (22) in an open pan (31) having an insertable frame (32) with edge surfaces (34) that are not significantly pressure deformable, where the inside side surfaces of the frame are parallel to the central axis B--B of the open pan, and where each article or compact is surrounded by fine particles of a separating material; (D) evacuating air from the container and sealing the articles or compacts inside the container by means of top lid (36); (E) hot pressing the compacts at a pressure from 352.5 kg/cm.sup.2 to 3,172 kg/cm.sup.2 to provide simultaneous hot pressing and densification of the articles or compacts; (F) gradually cooling and releasing the pressure; and, (G) separating the articles or compacts from the container, where there is no heating of the compacts in the process before step (E).

Method of making dimensionally reproducible compacts

A process of hot isostatic pressing of powders to form electrical contacts is characterized by the steps: (A) mixing powders, 1 in the Drawing, from metal containing powder or metal containing powder plus carbon powder, where at least one of Ag and Cu is present, (B) thermal cleaning treatment of the powder, 2 in the Drawing, (C) granulating the thermally treated powder, 3 in the Drawing, (D) uniaxially pressing the powders without heating, 5 in the Drawing, to provide a compact, (E) placing at least one compact in a pressure-transmitting, pressure-deformable container, 6 in the Drawing, and surrounding each compact with fine particles of a separating material, (F) evacuating air from the container, 7 in the Drawing, (G) sealing the compacts inside the container, 8 in the Drawing, (H) hot isostatic pressing, 9 in the Drawing, the compacts through the pressure transmitting material at a pressure from 352 kg/cm.sup.2 to 2,115 kg/cm.sup.2 and a temperature from 0.5.degree. C. to 100.degree. C. below the melting point of the lower melting powder constituent, to provide simultaneous hot-pressing and densification of the compacts, (I) gradually cooling and releasing the pressure on compacts, 10 in the Drawing, and (J) separating the compacts from the container, 11 in the Drawing, where there is no heating of the compacts in the process before step (H).

Hot isostatic pressing of high performance electrical components

A powdered metallurgical procedure for forming chromium copper contacts used in vacuum circuit interrupters, in which prealloyed powder formed by mixing to copper, chromium of between two to thirty-seven weight percent is rapidly solidified after melting at about 1100.degree. C. to 1500.degree. C. This powder may be blended with additional chromium of between 12 to 50 weight percent with a maximum of fifty-five weight percent of chromium in the final contact structure. This blended mixture may then be either (i) cold pressed at 100,000 psig. and vacuum sintered at 800.degree. to 1400.degree. C.; or (ii) be subjected to hot isostatic pressure of 10,000 to 30,000 psig. at between 700.degree. C. to 1080.degree. C.; or (iii) containing the blended copper-chromium powder and the additional chromium powder into an evacuated can and hot extruding the can between 400.degree. C. to 900.degree. C., to form the contacts.

Vacuum circuit interrupter contacts containing chromium dispersions

A low pressure plasma or laser spray metal deposition process for the manufacture of a vacuum interrupter contact with a tailored composition gradient through the thickness of the contact.

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Monroeville, PA, United States of America

Natraj C Iyer