Abstract: Fine-grained and/or equiaxed tungsten and/or rhenium coatings, substantially free from columnar structure, are deposited on substrates (especially graphite) by chemical vapor deposition by directing the flow of reactant gases to the substrate with high velocity and in close proximity thereto, most often at a velocity gradient of at least about 1050 and preferably at least about 2000 cm./cm.-sec. The deposition process is preferably conducted while moving the substrate so as to coat large areas thereof. By this method, tungsten and/or rhenium-coated articles useful as X-ray targets having excellent properties under conditions of rapid temperature cycling may be produced.
Abstract: Dental restorations are made of a palladium alloy which consists essentially of, on a weight basis, 50-85 percent palladium; 5-40 percent of at least one metal selected from the group consisting of copper and cobalt; 1-15 percent gallium; up to 5 percent of a modifier selected from the group consisting of nickel, gold, indium, ruthenium, tin and mixtures thereof; from 0.005 up to 1 percent, ordinarily less than about 0.2 percent, of an oxygen scavenging component which is a member selected from the group consisting of germanium, lithium, and mixtures thereof; and up to 0.5 percent of a grain refiner selected from the group consisting of rhenium and iridium. The alloy is free of boron.
Abstract: A method is taught for the in-situ precipitation of second phase materials, such as ceramic or intermetallic particles, in a substantial volume fraction of solvent metal matrix. The invention involves the propagating reaction of the second phase-forming constituents in a solvent metal medium to provide a porous composite of finely-dispersed second phase particles in the metal matrix. Exemplary materials include titanium carbide or titanium diboride in an aluminum matrix.
Type:
Grant
Filed:
August 30, 1989
Date of Patent:
April 17, 1990
Assignee:
Martin Marietta Corporation
Inventors:
William C. Moshier, John M. Brupbacher, Leontios Christodoulou, Dennis C. Nagle
Abstract: A long, linear composite article which is characterized in that a large number of composite filaments are present as spaced from one another in a continuous layer composed of copper, a copper alloy, niobium, tantalum or vanadium, each of said composite filaments having a structure that at least one strand of a linear body is surrounded by an aluminum alloy or niobium, said linear body being composed substantially of extremely fine, filamentary superconducting Nb.sub.3 Al compound having an average diameter of from about 0.03 .mu.m to about 1 .mu.m. The said composite article can be prepared by drawing a composite material composed of (a) an aluminum alloy and (b) niobium, together with copper or a copper alloy once or plural times repeatedly, until the average diameter of the aluminum alloy of (a) becomes about 1 .mu.m or less, and heat-treating the resultant linear composite material.
Abstract: This invention relates to a metallic-second phase composites comprising a matrix of titanium aluminide with discrete titanium silicide particles dispersed therein. The second phase dispersoid is stabilized during the process of in-situ formation by the presence of zirconium.
Type:
Grant
Filed:
September 26, 1988
Date of Patent:
April 10, 1990
Assignee:
Martin Marietta Corporation
Inventors:
Leontios Christodoulou, James C. Williams, Michael A. Riley
Abstract: A TiAl composition is prepared to have high strength and to have improved ductility by altering the atomic ratio of the titanium and aluminum to have what has been found to be a highly desirable effective aluminum concentration by addition of chromium, carbon and niobium according to the approximate formula Ti.sub.51-43 Al.sub.46-50 Cr.sub.2 Nb.sub.1-5 C.sub.0.1.
Abstract: A method is taught for the introduction of in-situ precipitated second phase materials, such as ceramic or intermetallic particles in a metal matrix, to a host metal. When an initial solvent-assisted reaction is utilized, metal-second phase composites having highly superior properties may be obtained. The invention may utilize the reaction of the second phase-forming constituents in a solvent metal medium to provide an intermediate material of finely-dispersed second phase particles in an intermediate metal matrix, in the form of a porous mass or sponge. Any desired loading of second phase in the final composite may be achieved by the admixture of this preformed intermediate material having a relatively high content of particulate material, with a molten host metal. Exemplary materials include titanium diboride in an aluminum matrix and titanium carbide in an aluminum matrix.
Type:
Grant
Filed:
September 29, 1987
Date of Patent:
April 10, 1990
Assignee:
Martin Marietta Corporation
Inventors:
Leontios Christodoulou, Dennis C. Nagle, John M. Brupbacher
Abstract: A molten metal is placed in contact with a bed of moving beads. The molten metal breaks up into fine particles which are rapidly cooled in contact with the beads and consequently acquire a structure which is typical for such rapid cooling.
Type:
Grant
Filed:
April 4, 1988
Date of Patent:
April 10, 1990
Assignee:
Battelle Memorial Institute
Inventors:
Peter Boswell, Dag F. Richter, Georges Haour
Abstract: Metal powder agglomerates of individual particles comprising (i) more than 70% by weight of one or more metals selected from the group consisting of the elements molybdenum, rhenium and tungsten and (ii) one or more binder metals selected from the group consisting of iron, cobalt, nickel, copper, silver, gold, palladium, platinum, rhodium, chromium and rhenium, wherein the individual particles have grain sizes of less than 2 .mu.m and all the metal particles lie side by side in uniform random distribution are useful as the powder required for producing shaped, sintered articles in a powder metallurgical preparation.
Type:
Grant
Filed:
January 19, 1989
Date of Patent:
April 10, 1990
Assignee:
Hermann C. Starck Berlin GmbH & Co. KG
Inventors:
Heinz-Eckert Schutz, Bernhard Szesny, Bruno E. Krismer
Abstract: A method is taught for the in-situ precipitation of second phase materials, such as ceramic or intermetallic particles, in a metallic matrix. By means of the Direct Addition Process, metal-second phase composites having highly superior properties may be obtained. Compacts of second phase-forming constituents and solvent metal are directly added to a molten metal bath to precipitate the second phase in-situ. Exemplary materials include titanium diboride or titanium carbide in an aluminum matrix.
Type:
Grant
Filed:
November 5, 1986
Date of Patent:
April 10, 1990
Assignee:
Martin Marietta Corporation
Inventors:
Dennis C. Nagle, John M. Brupbacher, Leontios Christodoulou
Abstract: This invention relates to a composite material comprising an in-situ precipitated second phase in an intermetallic matrix, and to the process for making such a composite.
Type:
Grant
Filed:
September 29, 1987
Date of Patent:
April 10, 1990
Assignee:
Martin Marietta Corporation
Inventors:
Dennis C. Nagle, John M. Brupbacher, Leontios Christodoulou
Abstract: A method is taught for the formation of intermetallic-second phase composite materials. The method involves the formation of a first metal-second phase composite comprising a relatively high loading of discrete, second phase particles distributed throughout a metal matrix, dilution of the first composite into an additional amount of metal to form a second composite comprising a lower loading of second phase particles within an intermediate metal matrix, and introduction of the second composite into another metal which is reactive with the intermediate metal matrix of the composite to form an intermetallic. A final intermetallic-second phase composite is thereby formed comprising a dispersion of discrete second phase particles throughout a final intermetallic matrix. The final intermetallic matrix may comprise a wide variety of intermetallic materials, with particular emphasis drawn to the aluminides and silicides. Exemplary intermetallics include Ti.sub.3 Al, TiAl, TiAl.sub.3, Ni.sub.3 Al, NiAl, Nb.sub.
Type:
Grant
Filed:
May 5, 1988
Date of Patent:
April 10, 1990
Assignee:
Martin Marietta Corporation
Inventors:
John M. Brupbacher, Leontios Christodoulou, Dennis C. Nagle
Abstract: This invention relates to a process for making in-situ precipitated second phase in an intermetallic matrix, which composite is rapidly solidified to form a product. The invention also relates to a rapidly solidified product comprising a second phase in both a stable particulate form and a metastable flake form dispersed in an intermetallic matrix.
Type:
Grant
Filed:
September 26, 1988
Date of Patent:
April 10, 1990
Assignee:
Martin Marietta Corporation
Inventors:
Stephen L. Kampe, John M. Brupbacher, Leontios Christodoulou, Dennis C. Nagle
Abstract: An austenitic alloy is provided having a desirable combination of properties by melting an alloy containing 25 to 27 weight percent chromium, 20 to 40 weight percent nickel, 5 to 7.0 percent molybdenum, 0.25 to 0.30 weight percent nitrogen, and the balance iron and incidental impurities. The alloys exhibit a CCCT value of greater than 49 degrees Centigrade, together with other desirable properties, can be so produced, while maintaining the level of resistance to stress corrosion cracking at a level higher than that of AISI Type 316L stainless steel.
Abstract: An electrically conductive composite material is formed by dispersing in a matrix metal another metal which is insoluble or slightly soluble with the matrix metal. The other metal is finely divided to an extent of not excessively lowering the conductivity and is mixed in the matrix metal in a particle amount such that respective particles keep a mutual distance effective to strengthen the composite material. The material is thereby sufficiently improved in the mechanical strength and wear resistance and remarkably reduced in high temperature deformation. Such conductive composite material can be obtained through a melt atomization.
Type:
Grant
Filed:
March 22, 1988
Date of Patent:
March 27, 1990
Assignees:
Matsushita Electric Works, Ltd., Unitika, Ltd.
Abstract: An alloy, adapted for use as a conductor for electrical resistors, consisting essentially of 30-45 wt. % Ni, 30-34 wt. % Cr, 25-35 wt. % Al and an effective amount of a corrosion inhibitor and stabilizer selected from the group consisting of transition metal elements and rare earth elements.
Abstract: A matrix of an Al-Ni base alloy or an Al-Si-Cu base alloy is strengthened by dispersion of particles of Ni, Si or at least one intermetallic compound selected from among AlNi, Al.sub.3 Ni, Al.sub.3 Ni.sub.2 and AlNi.sub.3.
Type:
Grant
Filed:
September 30, 1987
Date of Patent:
March 6, 1990
Assignee:
Ryobi Limited
Inventors:
Hiroyuki Ohmura, Morris E. Fine, Takao Miyoshi
Abstract: There is disclosed an antimony, tin and indium alloy which contains an additional element. The additional element is selected from the group consisting of titanium, aluminum, magnesium, manganese, silver, bismuth, germanium, lead, tellurium, gold, zinc, copper, palladium, nickel, iron, cobalt, and cadmium. The additional element substantially reduces arcing during the sputtering process used to make optical recording layers from the alloy.
Type:
Grant
Filed:
November 21, 1988
Date of Patent:
February 27, 1990
Inventors:
Yuan-Sheng Tyan, Pranab K. Raychaudhuri, Fridrich Vazan
Abstract: A filler for disintegrating projectiles for training ammunition composed essentially of a screened low carbon, unalloyed steel powder produced by atomizing a corresponding steel melt to form a steel powder, subsequently subjecting the powder to a reducing soft annealing treatment at a temperature of between about 900.degree. and 1050.degree. C., subjecting the annealed product to a comminuting (e.g., beating, impact and scrubbing) process followed by screening, wherein the comminuting process lasts longer than 60 minutes and the screened powder has a grain size below 0.315 mm, an uncompressed or apparent density of between 3.9 and about 4.6 g.multidot.cm.sup.-3, and is compressible in such a manner that the resulting density of a pressed body to be incorporated into the disintegrating projectile lies between about 6.5 and 7.15 g/cm.sup.3.
Abstract: A method for producing titanium alloy by the reduction of titanium tetrachloride and alloy components with a reducing metal agent, capable of continuously producing titanium alloy on an industrial scale. The temperature and pressure of the reaction zone for the reduction are kept above a melting point of the titanium alloy and above the vapor pressure of the reducing metal agent at that temperature respectively, so that the reducing metal agent and its chloride may be kept in a molten state but without boiling.