Carbide Formation, Decarburization Or Carbonizing Patents (Class 148/278)
-
Patent number: 12152284Abstract: This invention generally relates to a method for the thermomechanical treatment of semi-finished products of high-alloy steel. Typically, the method involves initially heating the steel semi-finished product to at least 1200° C., after which the semi-finished product is cooled and then reheated to a forming temperature, at which the semi-finished product is formed. Afterwards, the formed product is then cooled to ambient temperature.Type: GrantFiled: February 26, 2020Date of Patent: November 26, 2024Assignee: Zapadoceska univerzita v PlzniInventors: Bohuslav Masek, Ctibor Stadler
-
Patent number: 11932937Abstract: The invention relates to a method for producing a product, to a crucible and to the use of a layer of crystalline silicon nitride, the product being formed from a material consisting mainly of carbon or of a ceramic material, the product being coated with surface layer by chemical vapor deposition (CVD), wherein the product is coated with a surface layer of at least semi-crystalline, preferably crystalline silicon nitride (Si3N4), the surface layer being formed on the product at a process temperature of more than 1100° C. to 1700° C.Type: GrantFiled: March 1, 2018Date of Patent: March 19, 2024Assignee: SCHUNK KOHLENSTOFFTECHNIK GMBHInventors: Karl Brennfleck, Johannes Galle, Dennis Muscutt, Volker Rauhut
-
Patent number: 10329639Abstract: A multilayer steel includes a core formed of transformation-induced plasticity (TRIP) steel. A decarburized layer is exterior to the core on at least one side thereof. The decarburized layer has reduced carbon content relative to the core. A zinc-based layer is exterior to the decarburized layer. The decarburized layer may have a composition of at least 80 percent ferrite, such that LME is reduced or mitigated. In some configurations, the decarburized layer is between 10-50 microns thick. A method of creating a coated advanced high-strength steel component is also provided. An apparatus for forming a coated advanced high-strength steel is also provided. The core of the multilayer steel may have a carbon weight-percent of less than or equal to 0.4. The decarburized layer of the multilayer steel may have a carbon weight-percent of less than or equal to 50 percent of the carbon weight-percent of the core.Type: GrantFiled: August 4, 2017Date of Patent: June 25, 2019Assignee: GM Global Technology Operations LLC.Inventors: Charles Enloe, Curt D. Horvath, David Yang, Qi Lu, Wu Tao
-
Patent number: 10329640Abstract: A hearth roll for heat treatment furnaces has excellent build-up resistance, has a hexavalent-chromium-free thermal spray coating film formed on the roll surface thereof and is safe for the environment. A method for manufacturing a hearth roll for continuous annealing furnaces includes a first step of applying an aqueous solution containing chromium phosphate onto a thermal spray coating film formed on the roll surface of a hearth roll or impregnating the thermal spray coating film with the aqueous solution; and a second step of burning the hearth roll.Type: GrantFiled: June 29, 2015Date of Patent: June 25, 2019Assignee: NIPPON STEEL & SUMIKIN HARDFACING CO., LTD.Inventors: Yasushi Kurisu, Yu Li
-
Publication number: 20150083278Abstract: A base steel sheet has a hot-dip galvanized layer formed on a surface thereof, in which, in a steel sheet structure in a range of ? thickness to ? thickness centered around ¼ thickness of a sheet thickness from a surface, a volume fraction of a retained austenite phase is 5% or less, and a total volume fraction of phases of bainite, bainitic ferrite, fresh martensite, and tempered martensite is 40% or more, an average effective crystal grain diameter is 5.0 ?m or less, a maximum effective crystal grain diameter is 20 ?m or less, and a decarburized layer with a thickness of 0.01 ?m to 10.0 ?m is formed on a surface layer portion, in which a density of oxides dispersed in the decarburized layer is 1.0×1012 to 1.0×1016 oxides/m2, and an average grain diameter of the oxides is 500 nm or less.Type: ApplicationFiled: December 3, 2014Publication date: March 26, 2015Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Hiroyuki KAWATA, Naoki MARUYAMA, Akinobu MURASATO, Akinobu MINAMI, Takeshi YASUI, Takuya KUWAYAMA, Hiroyuki BAN, Kaoru HIRAMATSU
-
Patent number: 8980017Abstract: A method for manufacturing a steel plate provided with a layered structure. A method for manufacturing a steel plate includes: i) providing a high carbon steel plate; ii) homogenizing the high carbon steel plate; iii) transforming the high carbon steel plate into an austenitic phase by heating the high carbon steel plate; iv) contacting the high carbon steel plate with an oxidization gas and converting the high carbon steel plate into a steel plate comprising surface layers that are spaced apart from each other and are decarburized to be transformed into a ferritic phase, and a center layer that is located between the surface layers and is not decarburized; and v) cooling the high carbon steel plate and transforming the center layer into a martensitic phase.Type: GrantFiled: April 26, 2012Date of Patent: March 17, 2015Assignee: Postech Academy-Industry FoundationInventors: Yasushi Sasaki, Weonhui Lee
-
Patent number: 8864917Abstract: One exemplary embodiment includes a process for forming a hard carbide coating onto a low chromium-containing steel article via a chemical deposition process carried out on a particulate mix, in which molybdenum in the form of a compound FeMo or titanium in the form of a compound FeTi, or a mixture of FeMo and FeTi, may be added to the particulate mix used to form the coating.Type: GrantFiled: October 7, 2009Date of Patent: October 21, 2014Assignee: BorgWarner Inc.Inventor: Manoj Thete
-
Patent number: 8753755Abstract: A body, such as a pick tool for cutting coal, includes a steel substrate and a hard face structure fused to the steel substrate. The hard face structure includes at least 1 weight percent Si, at least 5 weight percent Cr and at least 40 weight percent W. Substantially the balance of the hard face structure includes carbon and an iron group metal M selected from Fe, Co, Ni and alloy combinations of these elements. The hard face structure includes a plurality of elongate or platelike micro-structures having a mean length of at least 1 micron, a plurality of nano-particles having a mean size of less than 200 nanometers, and a binder material.Type: GrantFiled: July 6, 2011Date of Patent: June 17, 2014Assignee: Element Six GmbHInventors: Igor Yuri Konyashin, Bernd Heinrich Ries, Frank Friedrich Lachmann, Kersten Heinrich Schafer
-
Publication number: 20130269837Abstract: A composition for diffusion surface alloying of ferrocarbon alloys with chromium, consisting essentially of, by weight, about 25%-40% ferrochromium; about 54%-74% aluminum oxide or mixtures of aluminum oxide, silicon oxide and magnesium oxide in a weight ratio of about 3:2:1; about 1%-3% ammonium chloride; and a reducing agent consisting essentially of about 0.1%-3% aluminum, about 0.1%-2% silicon, about 0.1%-1.5% magnesium, or about 0.1%-3% of a mixture of aluminum, silicon and magnesium in a weight ratio of about 3:2:1. A method for diffusion surface alloying of a ferrocarbon workpiece with chromium, comprising providing the above composition; exposing the workpiece to the composition; and heating the workpiece and composition for sufficient time and temperature to form a chromium containing diffusion layer on the surface of the workpiece.Type: ApplicationFiled: April 17, 2012Publication date: October 17, 2013Inventors: Lidiya Omovna CHUNYAYEVA, Oleg Nikolayevich CHUNYAYEV, Leonid Leonidovich TOVAZHNYANSKYY
-
Publication number: 20130048150Abstract: A method for producing a workpiece having properties which are adjustable across a wall thickness or strip thickness of the workpiece, includes the steps of subjecting the workpiece to a decarburizing annealing treatment under an oxidizing atmosphere and to an accelerated cooling and/or a cold forming for generating a property gradient of the workpiece, wherein the workpiece is made of an austenitic lightweight steel which has an alloy composition which includes by weight percent 0.2% to 1% carbon, 0.05% to <15% aluminum, 0.05% to 6.0% silicon, 9% to <30% manganese, and at least one element selected from the group consisting of chromium, copper, boron, titanium, zirconium, vanadium and niobium, wherein chromium=4.0%; titanium+zirconium=0.7%; niobium+vanadium=0.5%, boron=1%, the remainder iron including common steel companion elements.Type: ApplicationFiled: February 10, 2011Publication date: February 28, 2013Applicant: SALZGITTER FLACHSTAHL GMBHInventors: Daniela John, Manuel Otto, Rune Schmidt-Jürgensen, Thomas Evertz, Zacharias Georgeou, Bianca Springub
-
Publication number: 20130000789Abstract: A method for manufacturing a steel plate provided with a layered structure. A method for manufacturing a steel plate includes: i) providing a high carbon steel plate; ii) homogenizing the high carbon steel plate; iii) transforming the high carbon steel plate into an austenitic phase by heating the high carbon steel plate; iv) contacting the high carbon steel plate with an oxidization gas and converting the high carbon steel plate into a steel plate comprising surface layers that are spaced apart from each other and are decarburized to be transformed into a ferritic phase, and a center layer that is located between the surface layers and is not decarburized; and v) cooling the high carbon steel plate and transforming the center layer into a martensitic phase.Type: ApplicationFiled: April 26, 2012Publication date: January 3, 2013Applicant: POSTECH ACADEMY INDUSTRY FOUNDATIONInventors: Yasushi SASAKI, Weonhui Lee
-
Publication number: 20120325375Abstract: A steel sheet which is decarburized after being strip casted and a method for manufacturing the same are provided. A method for manufacturing the steel sheet includes i) providing molten iron, ii) removing sulfur, phosphorus, and silicon from the molten iron, iii) strip casting the molten iron and providing the steel sheet, and iv) heating and contacting the steel sheet with an oxidization gas while decarburizing the steel sheet.Type: ApplicationFiled: April 25, 2012Publication date: December 27, 2012Applicant: POSTECH ACADEMY-INDUSTRY FOUNDATIONInventors: Yasushi SASAKI, Ji-Ook PARK
-
Publication number: 20120301723Abstract: On the surface of a carbon substrate 41, a tantalum carbide coating film 42 is formed to coat the carbon substrate 41. The tantalum carbide coating film 42 has a maximum peak value of at least 80 degrees in an orientation angle of a (311) plane corresponding to a diffraction peak of tantalum carbide as determined by X-ray diffraction.Type: ApplicationFiled: December 28, 2010Publication date: November 29, 2012Applicant: TOYO TANSO CO., LTD.Inventor: Mika Kondo
-
Publication number: 20120273089Abstract: The present invention relates to a component {1, 2, 3, 4, 6) within the interior of a vehicle. Specifically, the present invention relates to a part of a seat-structure. The present invention further relates to a process to produce a component { 1, 2, 3, 4, 6) Within the interior of a vehicle.Type: ApplicationFiled: November 4, 2010Publication date: November 1, 2012Applicant: JOHNSON CONTROLS TECHNOLOGY COMPANYInventors: Daniel J. Sakkinen, Ornela Zekavica, Ronald G. Bedro, Frederic T. Winters, Nicholas L. Petouhoff, Anthony Kestian
-
Publication number: 20120217231Abstract: One example embodiment includes methods for making electron emitters. The electron emitter comprises a conductive member that defines a plurality of filament segments that are integral with each other. Each filament segment includes an intermediate portion and an interconnecting portion attached to an adjacent filament segment. The intermediate portions are substantially coplanar with each other and each intermediate portion includes a substantially planar electron emission surface.Type: ApplicationFiled: May 7, 2012Publication date: August 30, 2012Applicant: VARIAN MEDICAL SYSTEMS, INC.Inventors: Paul D. Moore, Stephen G. Bandy, Clifford K. Nishimoto, David H. Humber, Gary F. Virshup
-
Publication number: 20120171468Abstract: The present invention provides titanium material for a separator for solid polymer fuel cell use comprised of titanium which has a surface layer part where conductive compound particles are affixed, which is excellent in contact resistance between the separator surface and carbon paper and in durability, and which is low in cost and superior in recyclability and a method of production of the same. This titanium material for separator use has on the surface of the titanium base material a film comprised of the titanium compound particles made of titanium carbide, titanium nitride, or titanium carbonitride and titanium oxide. The film has a thickness of 0.1 to 1 ?m, the coverage rate is an area percentage of 20% or more, and the contents of carbon and nitrogen in the film total 5 to 40 at %. The titanium material for a separator is produced by annealing or shot blasting and pickling.Type: ApplicationFiled: July 28, 2010Publication date: July 5, 2012Inventors: Koki Tanaka, Kazuhiro Takahashi, Hiroshi Kihira, Kiyonori Tokuno
-
Patent number: 8158094Abstract: The present embodiments relate methods of preparing metal carbides, for example some embodiments relate to methods of preparing metal carbides that do not contain the formation of an intermediate oxide compound. Some embodiments relate to methods that do not employ hydrocarbons in the reaction. Some embodiments relate to a method of preparing metal carbides that involves citrate gel precursors and a non-hydrocarbon gas but does not use a hydrocarbon gas, does not form an oxide intermediate species and does not produce carbon monoxide. In some embodiments, the metal carbides are transition metal carbides.Type: GrantFiled: May 12, 2009Date of Patent: April 17, 2012Assignee: The United States of America, as represented by the Secretary of the NavyInventors: Karen Swider Lyons, Arnold M. Stux
-
Publication number: 20120006785Abstract: A low friction top coat over a multilayer metal/ceramic bondcoat provides a conductive substrate, such as a rotary tool, with wear resistance and corrosion resistance. The top coat further provides low friction and anti-stickiness as well as high compressive stress. The high compressive stress provided by the top coat protects against degradation of the tool due to abrasion and torsional and cyclic fatigue. Substrate temperature is strictly controlled during the coating process to preserve the bulk properties of the substrate and the coating. The described coating process is particularly useful when applied to shape memory alloys.Type: ApplicationFiled: May 9, 2011Publication date: January 12, 2012Inventors: Vladimir Gorokhovsky, Brad B. Heckerman, Yuhang Cheng
-
Publication number: 20110192499Abstract: One exemplary embodiment includes a process for forming a hard carbide coating onto a low chromium-containing steel article via a chemical deposition process carried out on a particulate mix, in which molybdenum in the form of a compound FeMo or titanium in the form of a compound FeTi, or a mixture of FeMo and FeTi, may be added to the particulate mix used to form the coating.Type: ApplicationFiled: October 7, 2009Publication date: August 11, 2011Applicant: BorgWarner Inc.Inventor: Manoj Thete
-
Patent number: 7524791Abstract: A method for producing a substrate having a carbon-doped titanium oxide layer, which is excellent in durability (high hardness, scratch resistance, wear resistance, chemical resistance, heat resistance) and functions as a visible light responding photocatalyst, is provided. The surface of a substrate, which has at least a surface layer comprising titanium, a titanium alloy, a titanium alloy oxide, or titanium oxide, is heat-treated in a combustion gas atmosphere of a gas consisting essentially of a hydrocarbon, or in a gas atmosphere consisting essentially of a hydrocarbon, such that the surface temperature of the substrate is 900 to 1,500° C.; or a combustion flame of a gas consisting essentially of a hydrocarbon, is directly struck against the surface of the substrate for heat treatment such that the surface temperature of the substrate is 900 to 1,500° C., thereby forming a carbon-doped titanium oxide layer, whereby the substrate having the carbon-doped titanium oxide layer is obtained.Type: GrantFiled: December 8, 2004Date of Patent: April 28, 2009Assignee: Central Research Institute of Electric Power IndustryInventor: Masahiro Furuya
-
Publication number: 20030175544Abstract: The invention includes a composition of matter which is resistant to metal dusting and a method for preventing metal dusting on metal surfaces exposed to carbon supersaturated environments.Type: ApplicationFiled: March 15, 2002Publication date: September 18, 2003Inventors: Trikur Anantharaman Ramanarayanan, ChangMin Chun
-
Patent number: 6592683Abstract: Ti alloy is embedded in a powder such as graphite and heated with the powder in an oxygen atmosphere. Oxygen atoms are diffused into the Ti alloy to form an oxygen diffusion layer of Ti—O solid solution, thereby increasing wear resistance of the valve. A poppet valve in an internal combustion engine may be made of such Ti alloy.Type: GrantFiled: November 21, 2001Date of Patent: July 15, 2003Assignee: Fuji Oozx Inc.Inventors: Masahito Hirose, Hiroaki Asanuma
-
Publication number: 20030116236Abstract: A method of manufacturing a grain-oriented steel sheet including hot-rolling a slab prepared using molten steel containing, by mass %, C of not more than about 0.08%, Si of about 2.0 to about 8.0% and Mn of about 0.005 to about 3.0%; optionally annealing the hot-rolled steel sheet; performing cold rolling once, or twice or more with intermediate annealing therebetween; performing primary recrystallization annealing in a low- or non-oxidizative atmosphere and adjusting the C content in the steel sheet after primary recrystallization annealing to be held in the range of about 0.005 to about 0.025 mass %; performing secondary recrystallization annealing; decarburization annealing; and, preferably, performing additional high-temperature continuous or batch annealing. A grain-oriented electrical steel sheet having a sufficiently high magnetic flux density and a low iron loss can be advantageously obtained even when it is manufactured without using an inhibitor.Type: ApplicationFiled: July 23, 2002Publication date: June 26, 2003Applicant: KAWASAKI STEEL CORPORATIONInventors: Yasuyuki Hayakawa, Hideo Yamagami, Seiji Okabe, Takeshi Imamura, Minoru Takashima, Mitsumasa Kurosawa
-
Publication number: 20030098093Abstract: Chain parts and other steel articles are provided with hard, wear-resistant carbide coatings by tumbling them in a heated retort with a particulate mix which includes a source of vanadium and/or niobium. The steel substrate comprises a steel having at least 0.2% carbon, preferably 0.7-1.2%. Where the chromium content of the steel is 4-12%, preferably 4-8%, the chemical deposition process includes drawing a small amount of chromium from the steel substrate into the vanadium or niobium carbide coating, where it is distributed substantially homogeneously, helping to provide adhesion strength to the coating.Type: ApplicationFiled: October 28, 2002Publication date: May 29, 2003Inventors: Yumin Wang, Yoshito Hanayama, Doug Fornell, Naosumi Tada, Kunihiko Mishima
-
Publication number: 20030056856Abstract: A Ti alloy poppet valve consists of a valve stem and a valve head, and is employed as intake or exhaust valve in an internal combustion engine of an automobile. O2 is put into the valve in a furnace at very slight amount and heated to introduce oxygen atoms into titanium of the valve to form a Ti—O interstitial solid solution without making titanium oxides. The valve is strengthened to increase hardness and wear resistance.Type: ApplicationFiled: October 21, 2002Publication date: March 27, 2003Inventors: Masahito Hirose, Hiroaki Asanuma
-
Patent number: 6503340Abstract: A method for producing chromium carbide coatings on steel provides a steel component having a surface which is carburized to contain at least about 0.40% by weight carbon and is followed by chromizing the surface to form a chromium carbide coating on the surface.Type: GrantFiled: August 2, 2000Date of Patent: January 7, 2003Assignees: The Babcock & Wilcox Company, McDermott Technology, Inc.Inventors: Michael Gold, Douglas D. Zeigler, George H. Harth, III, James M. Tanzosh, Dale LaCount, Steven C. Kung, Walter R. Mohn
-
Patent number: 6458218Abstract: A method is provided for depositing and thermally diffusing a boride or a carbide of a refractory metal on a substrate of a workpiece. A layer of the refractory metal is deposited on the substrate. At least one of the elements boron and carbon is deposited from a source other than the workpiece on the workpiece having the refractory metal layer. The workpiece is heated at a temperature and for a time period sufficient to diffuse at least a portion of the deposited refractory metal into the substrate and at least a portion of the deposited boron or carbon into the refractory metal layer and the substrate to form a substantially uniform and metallurgically bonded layer of the boride or carbide of the refractory metal on the substrate.Type: GrantFiled: January 16, 2001Date of Patent: October 1, 2002Assignee: Linamar CorporationInventor: Walter Savich
-
Patent number: 6348145Abstract: Coated steel articles are described which exhibit anti-coking properties, and a process for producing such articles by depositing an anti-coking coating on a matrix constituted by a steel, in general a refractory steel. These articles comprise: a refractory steel substrate comprising at least 0.2% by weight of carbon; a carbon-rich diffusion barrier; and an outer layer containing 90% to 99% by weight of chromium, coated by a cementation method. More particularly, the coated steel articles constitute tubes for reactors or stills used in various refining or petrochemical processes.Type: GrantFiled: July 6, 1998Date of Patent: February 19, 2002Assignee: Institut Francais du PetroleInventors: François Ropital, Paul Broutin, Marcel François, Alain Bertoli
-
Patent number: 6314764Abstract: A method of manufacturing a 1-inch diameter glass substrate for a magnetic disc in which a plate glass is press molded using a mold formed of a super-hard material and having a surface of a prescribed roughness. Ion implantation using nitrogen ions is performed on the surface of the mold, after which ion implantation using palladium ions, platinum ions, and carbon ions is performed in the order given. Finally, the surface of the mold is coated with a graphite or amorphous diamond-like carbon coating.Type: GrantFiled: February 16, 2001Date of Patent: November 13, 2001Assignee: Saatec Engineering CorporationInventor: Yasuaki Sakamoto
-
Patent number: 6314763Abstract: A method of manufacturing a 2-5 inch diameter glass substrate for a magnetic disc in which a plate glass is press molded using a mold formed of a super-hard material and having a surface of a prescribed roughness. Ion implantation using nitrogen ions is performed on the surface of the mold, after which ion implantation using palladium ions, platinum ions, and carbon ions is performed in the order given. Finally, the surface of the mold is coated with a graphite or amorphous diamond-like carbon coating.Type: GrantFiled: February 16, 2001Date of Patent: November 13, 2001Assignee: Saatec Engineering CorporationInventor: Yasuaki Sakamoto
-
Patent number: 5807441Abstract: A method of effectively manufacturing silicon steel sheets with highly accumulated {100} orientations having excellent magnetic characteristics by a single tight-coil annealing or multi-layer annealing. The method can be widely used in the manufacture of magnetic steel sheets. The silicon steel sheet with excellent magnetic characteristics can be obtained by subjecting a cold-rolled silicon steel sheet containing, on a weight basis, not more than 1% of C, 0.2 to 6.5% of Si, and 0.05 to 5.0% of Mn to a tight-coil annealing or a multilayer annealing together with a substance which accelerates decarburization or with a combination of a substance which accelerates decarburization and a substance which accelerates demanganization, as separators in annealing.Type: GrantFiled: October 17, 1996Date of Patent: September 15, 1998Assignee: Sumitomo Metal Industries, Ltd.Inventors: Toshiro Tomida, Shigeo Uenoya
-
Patent number: 5798002Abstract: In order to produce a carbon solid solution or carbide-containing surface layer on a substrate, the substrate is immersed into a cold bath of liquid active medium, and heated inside the liquid active medium by heating means immersed in the liquid active medium as well.Type: GrantFiled: December 2, 1996Date of Patent: August 25, 1998Inventor: Saveliy M. Gugel
-
Patent number: 5635243Abstract: Energy, such as from one or more lasers, is directed at the surface of a substrate to mobilize and vaporize a constituent element (e.g., carbide) within the substrate (e.g., steel). The vaporized constituent element is reacted by the energy to alter its physical structure (e.g., from carbon to diamond) to that of a composite material which is diffused back into the substrate as a composite material. An additional secondary element, which can be the same as or different from the constituent element, may optionally be directed (e.g., sprayed) onto the substrate to augment, enhance and/or modify the formation of the composite material, as well as to supply sufficient or additional material for fabricating one or more coatings on the surface of the substrate. The process can be carried out in an ambient environment (e.g., without a vacuum), and without pre-heating or post-cooling of the substrate. Articles formed by the disclosed processes are described, including three-dimensional objects.Type: GrantFiled: June 5, 1995Date of Patent: June 3, 1997Assignee: QQC, Inc.Inventors: Manuel C. Turchan, Pravin Mistry
-
Patent number: 5554415Abstract: Energy, such as from one or more lasers, is directed at the surface of a substrate to mobilize and vaporize a constituent element (e.g., carbide) within the substrate (e.g., steel). The vaporized constituent element is reacted by the energy to alter its physical structure (e.g., from carbon to diamond) to that of a composite material which is diffused back into the substrate as a composite material. An additional secondary element, which can be the same as or different from the constituent element, may optionally be directed (e.g., sprayed) onto the substrate to augment, enhance and/or modify the formation of the composite material, as well as to supply sufficient or additional material for fabricating one or more coatings on the surface of the substrate. The process can be carried out in an ambient environment (e.g., without a vacuum), and without pre-heating or post-cooling of the substrate.Type: GrantFiled: January 18, 1994Date of Patent: September 10, 1996Assignee: QQC, Inc.Inventors: Manuel C. Turchan, Pravin Mistry
-
Patent number: 5549973Abstract: A metal or alloy nanoparticle is provided which exhibits hysteresis at room temperature having a carbon coating. The nanoparticle has a diameter in the range of approximately 0.5 to 50 nm, and may crystalline or amorphous. The metal, alloy, or metal carbide nanoparticle is formed by preparing graphite rods which are packed with the magnetic metal or alloy. or an oxide of the metal or alloy. The packed graphite rods are subjected to a carbon arc discharge to produce soot containing metal, alloy, or metal carbide nanoparticles and non-magnetic species. The spot is subsequently subjected to a magnetic field gradient to separate the metal, alloy, or metal carbide nanoparticles from the non-magnetic species.Type: GrantFiled: June 24, 1994Date of Patent: August 27, 1996Assignee: Carnegie Mellon UniversityInventors: Sara Majetich, Michael McHenry, John H. Scott, Elaine Brunsman, Scott Kirkpatrick
-
Patent number: 5456986Abstract: A magnetic metal or metal carbide nanoparticle is provided having a carbon coating. The nanoparticle has a diameter in the range of approximately 5 to 60 nm, and may be crystalline or amorphous. The magnetic metal or metal carbide nanoparticle is formed by preparing graphite rods which are packed with a magnetic metal oxide. The packed graphite rods are subjected to a carbon arc discharge to produce soot containing magnetic metal or metal carbide nanoparticles and non-magnetic species. The soot is subsequently subjected to a magnetic field gradient to separate the magnetic metal or metal carbide nanoparticles from the non-magnetic species. Ferromagnetic or paramagnetic compounds are made by starting with graphite rods packed with the oxides of iron, cobalt, nickel and manganese bismuth, or a rare earth element excluding lanthanum, lutetium and promethium, or a paramagnetic transition metal.Type: GrantFiled: June 30, 1993Date of Patent: October 10, 1995Assignee: Carnegie Mellon UniversityInventors: Sara Majetich, Michael McHenry, Joseph Artman, Stuart Staley
-
Patent number: 5401339Abstract: A process for producing low-cost atmospheres suitable for decarburize annealing carbon steels from non-cryogenically generated nitrogen containing up to 1.54 residual oxygen by catalytically deoxygenating a non-cryogenically generated nitrogen stream at low temperatures with a hydrocarbon gas and mixing the deoxygenated stream with an economical amount of hydrogen prior to introduction into the furnace for annealing. The process includes the use of 1) hydrocarbon gas to convert residual oxygen to a mixture of carbon dioxide and moisture at low temperatures and 2) mixing the deoxygenated stream with a sufficient amount of hydrogen to maintain a pH.sub.2 /pH.sub.2 O ratio of at least 2 in the furnace.Type: GrantFiled: February 10, 1994Date of Patent: March 28, 1995Assignee: Air Products and Chemicals, Inc.Inventors: Diwakar Garg, Brian B. Bonner, Kerry R. Berger
-
Patent number: 5395461Abstract: A method of producing a titanium material having enhanced resistance to hydrogen absorption in aqueous hydrogen sulfide solutions which comprises removing a layer of at least 0.5 .mu.m depth from the surface of a titanium material that has been annealed after cold rolling so that titanium nitride, titanium carbide, or titanium carbonitride formed on the surface is removed. It is preferable that the titanium material has no flaw in the depth beyond 10 .mu.m from the surface. It is desirable that the titanium material is polished so that it has a surface roughness Rmax not exceeding 3.0 .mu.m. It is also preferred that the titanium surface has an oxide film ranging in thickness from 15 to 500 nm formed thereon.Type: GrantFiled: March 14, 1994Date of Patent: March 7, 1995Assignee: Nippon Mining & Metals Co., Ltd.Inventors: Kazuhiro Taki, Akio Saito
-
Patent number: 5234721Abstract: A method for forming a carbide coating of Group IVA, VA and VIA transition metals and their alloys. The metal to be coated is heated in a bath of molten alkali or alkaline earth metal containing carbon. There is also provided a method for preparing a metal surface for carburization by heating the metal in a nitrogen-containing atmosphere.Type: GrantFiled: May 26, 1989Date of Patent: August 10, 1993Assignee: Rostoker, Inc.Inventors: William Rostoker, Julius J. Bonini, Gary W. Klimczak
-
Titanium nitride coated silicon carbide materials with an interlayer resistant to carbon-diffusivity
Patent number: 5167943Abstract: Finely divided silicon carbide materials, particularly powders, whiskers and short fibers, are provided with a titanium nitride surface coating by the process of (i) placing a low carbon diffusivity layer atop the silicon carbon, (ii) placing a titanium metal coating atop the low carbon diffusivity layer, and (iii) nitriding the titanium metal.Type: GrantFiled: December 17, 1990Date of Patent: December 1, 1992Assignee: Norton CompanyInventors: Shih-Yee Kuo, Hyun-Sam Cho, Jeffrey D. Bright -
Patent number: 5004489Abstract: The invention concerns glass-metal sealing comprising effecting on a metallic piece, in particular an alloy based on iron and nickel or iron, nickel and cobalt, first of all a decarburization under an atmosphere, at a temperature of between 950.degree. C. and 1,150.degree. C., formed by hydrogen (10 to 99%), water vapor (1 to 8%), with a ratio hydrogen/water vapor higher than five, the possible remainder being nitrogen, then an oxidation under an atmosphere formed by an inert vector gas such as nitrogen, either at a temperature of 600.degree. C. to 800.degree. C. and with a water vapor content of 8% to 2%; or at a temperature of 900.degree. C. to 1,100.degree. C. and with a water vapor content of 4% to 0.5%; then establishing the connection.Type: GrantFiled: February 22, 1990Date of Patent: April 2, 1991Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges ClaudeInventors: Frederic Rotman, Yannick Rancon, Philippe Queille, Michel Olivier
-
Patent number: 4935073Abstract: Protective coatings are applied to substrate metals by coating the metal surface, e.g. by dipping the substrate metal in a molten alloy of the coating metals, and then exposing the coating at an elevated temperature to an atmosphere containing a reactive gaseous species which forms an oxide, a nitride, a carbide, a boride or a silicide. The coating material is a mixture of the metals M.sub.1 and M.sub.2, M.sub.1 being zirconium and/or titanium, which forms a stable oxide, nitride, carbide, boride or silicide under the prevailing conditions. The metal M.sub.2 does not form a stable oxide, nitride, carbide, boride or silicide. M.sub.2 serves to bond the oxide, etc. of M.sub.1 to the substrate metal. Mixtures of M.sub.1 and/or M.sub.2 metals may be employed. This method is much easier to carry out than prior methods and forms superior coatings. Eutectic alloys of M.sub.1 and M.sub.2 which melt substantially lower than the melting point of the substrate metal are preferred.Type: GrantFiled: October 21, 1987Date of Patent: June 19, 1990Assignee: SRI InternationalInventors: Robert W. Bartlett, Paul J. Jorgensen, Ibrahim M. Allam, David J. Rowcliffe
-
Patent number: 4844949Abstract: A method of forming a surface layer of carbide, nitride, carbonitride, or solid-solution on the surface of a material to be treated, which comprises disposing in a fluidized bed furnace a treating agent comprising a powder of a refractory material, and a powder of a metal for forming a carbide, nitride, carbonitride or solid-solution or a powder of an alloy thereof, introducing a fluidizing gas into the fluidized bed furnace to fluidize the treating agent and form a fluidized layer, disposing the material to be treated in the fluidized layer, and introducing a predetermined amount of halide into the fluidized layer, and an apparatus for forming the surface layer on the material to be treated, comprising a furnace body for forming the surface layer in the fluidized layer of the treating agent, a heating furnace for heating the fluidized layer, a halide supply pipe in communication with the outside of the furnace body, and a halide gas jetting pipe disposed within the furnace body, which is connected to the halType: GrantFiled: September 23, 1988Date of Patent: July 4, 1989Assignee: Kabushiki Kaisha Toyota Chuo KenkyushoInventors: Tohru Arai, Junji Endo, Hiromasa Takeda