Combined Carburizing And Nitriding (e.g., Carbonitriding, Nitrocarburizing, Etc.) Patents (Class 148/218)
  • Patent number: 6948247
    Abstract: A cylindrical roller bearing or needle roller bearing for use with a rolling raceway surface is subjected to a carbonitriding treatment to produce a layer containing 30 to 80% retained austenite in the vicinity of its surface that contacts a carburized layer of a rolling raceway surface of a roller bearing. The amount of retained austenite of the surface layer of the roller bearing is increased by about 30%. The surface layer is then heat treated to apply a residual compression stress. The surface then receives surface finishing to produce micro concavo-convex portions in a random direction.
    Type: Grant
    Filed: March 20, 2000
    Date of Patent: September 27, 2005
    Assignee: Komatsu Ltd.
    Inventors: Osamu Kodama, Kaoru Hasegawa, Nobuaki Kawasaki
  • Patent number: 6846367
    Abstract: Disclosed is a method for improving the wear- and corrosion-resistance of a chromium-plated steel substrate by heat-treating the chromium-plated steel substrate under optimum conditions to inhibit a drop in corrosion-resistance of a steel substrate due to fine cracks formed at a chromium layer, and to improve a hardness of the chromium layer. The heat-treating method comprises the steps of: plating the chromium layer onto the steel substrate; and heating the chromium-plated steel substrate in an oxidizing gas environment at above atmospheric pressure to form oxidized layers containing magnetite (Fe3O4) on the surface of the steel substrate, the surface of the steel substrate being partly exposed to the air through penetrating cracks formed in the chromium layer.
    Type: Grant
    Filed: February 11, 2003
    Date of Patent: January 25, 2005
    Assignee: Korea Institute of Machinery & Materials
    Inventors: Kee-Seok Nam, Sik-Cheol Kwon, Do-Yon Chang, Kyu-Hwan Lee, Man Kim, Dong-Soo Kim, Gun-Hwan Lee
  • Publication number: 20040256029
    Abstract: There is provided an inexpensive rolling element used under high interface pressure such as induction hardened gears, the rolling element being improved in the seizure resistance of its tooth flanks and having a temper hardness of HRC 50 or more at 300° C. To this end, the rolling element is made from a steel material containing at least 0.45 to 1.5 wt % C and one or more alloy elements selected from 0.1 to 0.5 wt % V and 0.3 to 1.5 wt % Cr, and has a rolling contact surface layer having a structure tempered at low temperature in which 2 to 18% by volume cementite disperses in a martensite parent phase formed by induction heating and cooling and containing 0.25 to 0.8 wt % carbon solid-dissolving therein.
    Type: Application
    Filed: March 1, 2004
    Publication date: December 23, 2004
    Applicant: KOMATSU LTD.
    Inventors: Takemori Takayama, Masanari Furumoto, Chikara Nakao, Noriko Morioka
  • Publication number: 20040250920
    Abstract: The present invention concerns a method for generating nanostructures in order to obtain in an area on the surface of a metal piece (10) a nanostructured layer of defined thickness, characterized in that it comprises: a step for projecting onto an impact point in the area of the surface of the piece (10) to be treated, for a given duration, at a given speed and at variable incidences at the same impact point, a given quantity of perfectly spherical balls (22) of given dimensions, reused continuously during the projection; repetition of the preceding step with a shift of the impact point so that the impact points as a group cover the entire surface of the piece to be treated; a step for treatment by diffusion of chemical compounds into the nanostructured layer generated during the step for implementing the method for generating nanostructures.
    Type: Application
    Filed: May 5, 2003
    Publication date: December 16, 2004
    Inventors: Jian Lu, Ke Lu
  • Publication number: 20040250921
    Abstract: A vacuum carbonitriding method includes: performing a vacuum carburizing process on an object to be treated (a workpiece) in a heat treating furnace under reduced pressures by supplying a carburizing gas into the furnace that has been heated to a predetermined carburizing temperature; stopping supply of the carburizing gas while keeping the carburizing temperature so as to diffuse carbon in the workpiece under reduced pressures; and performing a nitriding process on the workpiece by supplying a nitriding gas into the furnace under reduced pressures after lowering the furnace temperature. Required heat treatment qualities such as surface hardness, effective case depth, toughness and the like can be achieved in a short time with reproducibility even in a case of workpiece made of low-grade steel or case-hardened steel.
    Type: Application
    Filed: February 18, 2004
    Publication date: December 16, 2004
    Inventor: Kazuyoshi Yamaguchi
  • Publication number: 20040231753
    Abstract: The method for enriching steel with carbon by carbon oxide comprises a step involving heating to a temperature of enrichment in a furnace in a gaseous phase, then an enrichment step involving the introduction of a gas containing carbon oxide. According to the invention, atomic hydrogen is formed in said gaseous phase prior to the enrichment phase, said atomic hydrogen being of a sufficient amount to suppress interface resistance to the transfer of carbon and to avoid surface oxidation of said steel.
    Type: Application
    Filed: June 2, 2004
    Publication date: November 25, 2004
    Inventor: Michel Gantois
  • Publication number: 20040045636
    Abstract: A surface treatment method in which a surface of a part (7) is contacted with at least one activated species. The activated species is obtained by activating a gaseous medium containing at least two of the following elements: carbon, nitrogen, boron and oxygen. Preferably, the activated species is a neutral excited CN species. The activated species brings at least one interstitial element to the metal part (7) surface which is borne and maintained at a temperature enabling the interstitial element to be diffused into a surface layer of the metal part (7).
    Type: Application
    Filed: February 21, 2003
    Publication date: March 11, 2004
    Inventors: Laurent Poirier, Jean-Paul Lebrun, Bernard Delmas
  • Patent number: 6656293
    Abstract: A method for treating a surface of a first component wherein at least a portion of the surface of the first component contacts a surface of a second component. The method includes forming a compound layer at at least a portion of the surface of the first component by a thermochemical diffusion treatment and isotropically finishing the at least a portion of the surface of the first component that contacts the surface of the second component.
    Type: Grant
    Filed: December 10, 2001
    Date of Patent: December 2, 2003
    Assignee: Caterpillar Inc
    Inventors: Jared A Black, Matthew Thomas Kiser, Gary Leroy Biltgen
  • Patent number: 6623567
    Abstract: A method for high concentration carburizing and quenching of steel is provided which is carried out by a treatment process including the steps of carbonitriding the steel at temperatures of from about 800 to about 880° C., and subsequently quenching the steel at a temperature higher than the carbonitriding temperature. In the carbonitriding step, the steel is treated with carbon concentrations in a carburizing atmosphere taken as about 0.7 to about 1.2% and with 3 to 8% of ammonia gas (NH3) being added, for example. This dissolves network-like carbide in austenite and, when the austenite is transformed into martensite by quenching, distributes the dissolved carbide in the form of granules approximately uniformly in the martensite.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: September 23, 2003
    Assignee: Nakamura Industrial Co., Ltd.
    Inventors: Shotaro Nakamura, Noboru Kuwayama
  • Publication number: 20030075244
    Abstract: A bearing pressure-resistant member, including a matrix and a carbide dispersed in the matrix, the carbide having an average particle size of not more than 0.3 &mgr;m. A carbon (C) content in an outer surface of the bearing pressure-resistant member is in a range of 0.6 to 1.5 mass percent. A process for making the bearing pressure-resistant member including subjecting a workpiece containing C to either of gas carburizing and gas carbonitriding to enhance the C content in the outer surface of the workpiece to 0.6 to 1.5 mass percent, holding the workpiece at a first temperature not more than an Ac1 transformation point under reduced pressure, heating the workpiece to a second temperature not less than the Ac1 transformation point under reduced pressure, followed by holding the workpiece at the second temperature, and subjecting the workpiece to quenching.
    Type: Application
    Filed: May 3, 2002
    Publication date: April 24, 2003
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Yutaka Kurebayashi, Toshimitsu Kimura, Takuro Yamaguchi, Keizo Otani, Noriko Uchiyama
  • Publication number: 20020179188
    Abstract: A high strength gear is provided which comprises a base metal of an iron-base alloy, the base metal being carburized or carbonitrided and having a tooth surface, and a coating containing Fe nitride and/or Fe carbonitride, formed on the tooth surface. A method of forming a high strength gear is also provided.
    Type: Application
    Filed: February 20, 2002
    Publication date: December 5, 2002
    Applicant: NISSAN MOTOR CO., LTD. and KABUSHIKI KAISHA KOBE SEIKO SHO
    Inventors: Takuro Yamaguchi, Keizo Otani, Jun Katoh, Toshiki Satou, Satoshi Abe, Masakazu Ikeda
  • Publication number: 20020166607
    Abstract: A process for low-pressure carbonitriding of steel parts is disclosed according to which the parts are carburized at low pressure between roughly 780° C. and 1050° C., utilizing a carbon releasing gas at a pressure of less than 500 mbars and are subsequently nitrided utilizing a nitrogen releasing gas comprising NH3. The nitrogen releasing gas is fed into the treating chamber at the end of the carburization phase at a temperature range of roughly 780° C. to 950° C., starting from a low pressure and ending at a pressure of less than 1000 mbars, for nitriding the parts.
    Type: Application
    Filed: April 2, 2002
    Publication date: November 14, 2002
    Inventors: Herwig Altena, Franz Schrank
  • Patent number: 6454880
    Abstract: Multi-layer material for die cast tooling component includes a low to medium carbon steel with alloying amounts of vanadium, manganese and molybdenum, quenched to at least 10 Bar and nitrocarburized to achieve a multiple layer structure with at least an outside lubricious layer, retaining hardness in the core. The method for producing the multi-layer material includes alloying the core material, forming into desired net shape, quenching and nitrocarburizing. A high endurance die cast tooling component for use in tooling applications includes a core material of at least 80 percent by volume martensite with no more than 15 percent by volume of retained austenite with at least two surface layers for lubricity and endurance. The tooling components may include shot sleeves, plungers, plunger tips, bushings, and core pins.
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: September 24, 2002
    Inventor: Herbert (Lonny) A. Rickman, Jr.
  • Patent number: 6447619
    Abstract: High surface pressure resistant steel parts and their producing methods are disclosed. These steel parts are useful as gears, cams, bearings and similar high-strength compact steel articles which are required to have wear resistance and strength to withstand fatigue in rolling or rolling-slipping applications. In a steel part formed according to the invention, a fine nitride and/or carbonitride having at least an average grain size of 0.3 &mgr;m or less is dispersed in the contact surface structure; a multi phase structure composed of martensite, which is divided into extremely fine pieces, forming a disordered shape, by the nitride and/or carbonitride, is formed; and a carbide having a grain size of 3 &mgr;m or less is dispersed to increase the hardness of the surface.
    Type: Grant
    Filed: November 8, 2000
    Date of Patent: September 10, 2002
    Assignee: Komatsu Ltd.
    Inventors: Takemori Takayama, Naoji Hamasaka
  • Publication number: 20020119858
    Abstract: A rolling element for a continuously variable transmission, including a plurality of rolling members having rolling contact portions that come into rolling contact with each other via lubricating oil. At least one of the rolling contact portions includes an outer surface layer having a surface microhardness of not less than Hv 750, a surface residual compressive stress of not less than 1000 MPa and a residual austenite content of not more than 10% by volume.
    Type: Application
    Filed: November 30, 2001
    Publication date: August 29, 2002
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Nobuo Kino, Noriko Uchiyama, Takuro Yamaguchi, Keizo Otani
  • Patent number: 6406560
    Abstract: A method is provided for the thermal treatment of metal workpieces in a gas atmosphere containing nitrogen, in particular for nitrocarburizing iron articles. In order to obtain enhanced resistance to wear and corrosion in the treated workpieces, the nitrogen and carbon content present in the connecting layer of the case of the treated workpieces are intentionally adjusted by appropriately selecting the nitride coefficient KN and the carburizing coefficient KC of a reaction gas that contains ammonia, whereby hydrocarbons are added to the reaction gas for producing a relatively high carbon content in the connecting layer.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: June 18, 2002
    Assignee: Ipsen International GmbH
    Inventors: Wolfgang Lerche, Bernd Edenhofer, Michael Lohrmann
  • Publication number: 20020050307
    Abstract: A method for high concentration carburizing and quenching of steel is provided which is carried out by a treatment process including the steps of carbonitriding the steel at temperatures of from about 800 to about 880° C., and subsequently quenching the steel at a temperature higher than the carbonitriding temperature. In the carbonitriding step, the steel is treated with carbon concentrations in a carburizing atmosphere taken as about 0.7 to about 1.2% and with 3 to 8% of ammonia gas (NH3) being added, for example. This dissolves network-like carbide in austenite and, when the austenite is transformed into martensite by quenching, distributes the dissolved carbide in the form of granules approximately uniformly in the martensite.
    Type: Application
    Filed: May 10, 2001
    Publication date: May 2, 2002
    Applicant: NAKAMURA INDUSTRIAL CO., LTD.
    Inventors: Shotaro Nakamura, Noboru Kuwayama
  • Publication number: 20020000267
    Abstract: A steel for a high bearing pressure-resistant member, having a high machinability. The steel is formed of a machine structural steel comprising carbon in an amount ranging from 0.15 to 0.25% by weight, silicon in an amount of not less than 0.4% by weight, nickel in an amount ranging from 1 to 3% by weight, chromium in an amount ranging from 1.2 to 3.2% by weight, and molybdenum in an amount ranging from 0.25 to 2.0% by weight. The machine structural steel contains carbide precipitated under a heat treatment for spheroidizing. The carbide has an average particle size of not larger than 1 &mgr;m and the maximum particle size of not larger than 3 &mgr;m.
    Type: Application
    Filed: May 15, 2001
    Publication date: January 3, 2002
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Toshimitu Kimura, Tatsuomi Nakayama, Hiroo Ueda, Noriko Uchiyama
  • Patent number: 6328819
    Abstract: A method is provided for heat treatment of metal workpieces obtain a substantially uniform nitride layer, even in workpieces comprising high alloy iron articles. The following method steps are provided: a) heating the workpieces to a temperature between 400° C. and 500° C. in a gas atmosphere comprising only ammonia; b) continuing to heat the workpieces to a temperature between 500° C. and 700° C. in a gas atmosphere containing ammonia and an added oxidizing agent; c) maintaining the workpieces at this temperature and in this gas atmosphere for a period of between 0.1 hour and 5 hours; d) continuing to maintain the workpieces at this temperature for a period of between 1 hour and 100 hours in a gas atmosphere containing ammonia or containing ammonia and a carbon-releasing substance; and, e) cooling the workpieces to room temperature.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: December 11, 2001
    Assignee: Ipsen International GmbH
    Inventors: Wolfgang Lerche, Bernd Edenhofer, Michael Lohrmann
  • Patent number: 6309475
    Abstract: For easily producing a toothed material for high-strength gears etc. with a plastic working technique, deformation resistance occurring in plastic working is reduced and stable high precision plastic working is enabled at lower temperatures. One or more types of heat treatment selected from carburization, carbonitriding and nitriding and a hardening process are applied to an alloy steel material containing: iron as a main component; at least 1.0 to 4.5 wt % Si; 0.35 wt % or less C; and balance Fe and unavoidable impurities, whereby a rolling element is obtained which has a surface layer mainly composed of martensite containing no &agr;-Fe phase and of residual austenite and an inner structure cooled from an (&agr;+&ggr;)-Fe two phase region.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: October 30, 2001
    Assignee: Komatsu Ltd.
    Inventors: Takemori Takayama, Chikara Nakao
  • Patent number: 6258179
    Abstract: A carburizing method is described which is capable of dispersing cementite grains in the surface of steel uniformly and finely as not to affect fatigue strength and capable of fining the crystal grains of austenite. To prevent cementite precipitation during high temperature carburization at 980° C. or more, steel contains Al in an amount in the range of 0.05≦[Al wt %]≦2.0 and Cr in an amount in the range of 0.3≦[Cr wt %]≦4.0, and the composition of the steel satisfies the requirement represented by 1.9≧−5.6[Si wt %]−7.2[Al wt %]+1.1[Mn wt %]+2.1[Cr wt %]−0.9[Ni wt %]+1.1[Mo wt %]+0.6[W wt %]+4.3[V wt %].
    Type: Grant
    Filed: August 10, 1998
    Date of Patent: July 10, 2001
    Assignee: Komatsu Ltd.
    Inventors: Takemori Takayama, Naoji Hamasaka
  • Patent number: 6248186
    Abstract: A ball-and-roller bearing is disclosed having an inner ring, an outer ring arranged on the axis of the inner ring and rotating around the co-axis relative to the inner ring, and a rolling body interposed between the inner ring and the outer ring and rolling with rotation of the outer ring relative to the inner ring. One of the inner ring, the outer ring, and the rolling body has a core member made from an alloy containing iron, at least one of 0.2 to 1.0% by weight of silicon and 0.2 to 1.5% by weight of manganese, 7.0 to 11.0% by weight of chromium, 1.5 to 6.0% by weight of molybdenum, and 0.5 to 8.0% by weight of cobalt, and a case hardened surface layer. Also disclosed is the method of manufacturing the bearing by forming a core member of the alloy, forming a case hardened layer containing 0.9 to 1.
    Type: Grant
    Filed: July 2, 1999
    Date of Patent: June 19, 2001
    Assignee: NSK Ltd.
    Inventors: Kenji Yamamura, Susumu Tanaka, Manabu Ohori
  • Patent number: 6235128
    Abstract: The present invention is a unique sequential process for treating carbon and alloy steels to improve resistance to tribological stresses while reducing conventional processing time required to obtain articles having a similar hardness. This process comprises carburizing or carbonitriding the article, tempering the carburized or carbonitrided article, net-shaping (machining) the tempered article, and plasma (ion) nitriding the tempered article for a significantly reduced period of time versus conventional plasma (ion) nitriding.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: May 22, 2001
    Inventors: John C. Chang, John Joseph Krieg, Richard Blanco Roe, Steve Stormzand, Tony Wu, Lynn Lu, Jeffrey W. Kunitzer
  • Patent number: 6129988
    Abstract: The present invention generally describes methods for modifying MCrAlY coatings by using gaseous carburization, gaseous nitriding or gaseous carbonitriding. The modified MCrAlY coatings are useful in thermal barrier coating systems, which may be used in gas turbine engines.
    Type: Grant
    Filed: August 14, 1998
    Date of Patent: October 10, 2000
    Assignee: Siemens Westinghouse Power Corporation
    Inventors: Steven J. Vance, John G. Goedjen, Stephen M. Sabol, Kelly M. Sloan
  • Patent number: 6090225
    Abstract: Process for manufacturing a mechanical component made of steel, in which a blank of the steel component is manufactured and a high-temperature carburizing or carbonitriding treatment of at least part of the surface of the blank of the component is carried out, the chemical composition of the steel of which the component is composed comprises, by weight: 0.15%.ltoreq.C.ltoreq.0.35%; 0%.ltoreq.Si.ltoreq.0.6%; 0%.ltoreq.Mn+Cr+Ni+Mo.ltoreq.5%; 0%.ltoreq.Al.ltoreq.0.1%; 0%.ltoreq.Cu.ltoreq.0.5%; 0%.ltoreq.Ti.ltoreq.0.05%; 0.004%.ltoreq.N.ltoreq.0.02%; 0%.ltoreq.S.ltoreq.0.15%; P.ltoreq.0.03%; optionally, up to 0.02% tellurium, up to 0.04% selenium, up to 0.07% lead, up to 0.005% calcium, the balance being iron and impurities resulting from the smelting; the chemical composition being adjusted so that the Jominy curve of the steel is such that: 45 HRC.ltoreq.J.sub.3 .ltoreq.50 HRC; 39 HRC.ltoreq.J.sub.11 .ltoreq.47 HRC; 31 HRC.ltoreq.J.sub.25 .ltoreq.40 HRC; the average values J.sub.3m, J.sub.11m and J.sub.
    Type: Grant
    Filed: July 9, 1998
    Date of Patent: July 18, 2000
    Assignee: Ascometal (Societe Anonyme)
    Inventor: Claude Pichard
  • Patent number: 5916383
    Abstract: A method for shot peening a hard metal product that has a hardened surface. The method includes projecting shot on the hardened surface of the hard metal product. The ratio of the Vickers hardness of the shot to that of the hardened surface is 0.8-1.6, and the diameter of the shot is 30-250.mu..
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: June 29, 1999
    Assignee: Sintokogio, Ltd.
    Inventors: Hitoshi Rokutanda, Toru Takahashi, Junkou Kurosaki, Toshiroh Ito
  • Patent number: 5912399
    Abstract: A new tungsten compound is formed by reacting ammonium metatungstate with guanidine carbonate. Such a compound can be converted to metallic tungsten, tungsten carbide or oxycarbide, and tungsten nitride or oxynitride. One can also make multiphase composite particles based on molybdenum, tungsten or their compounds (such as carbide or nitride), and at least one other metallic phase, such as cobalt, copper, nickel, iron or silver. The process involves first dispersing particles of a refractory metal or its compounds in a liquid medium, followed by inducing a chemical reaction in the liquid phase to generate a new solid phase which coats or mixes with the dispersed particles. The solid phase includes elements required in the final composite. After removing the liquid phase, the remaining solid is converted by hydrogen reduction into the final products.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: June 15, 1999
    Assignee: Materials Modification Inc.
    Inventors: Chunzhe C. Yu, Reshma Kumar
  • Patent number: 5900126
    Abstract: An improved magnetic-recording disk and a process for manufacturing magnetic-recording disks are disclosed. A precision cold-rolled authentic stainless steel is the substrate for a magnetic-recording disk. The surface of the substrate may be hardened by plasma nitriding, plasma carburizing, or plasma carbonitriding. A hard coating may be applied to the substrate by evaporative reactive ion plating or reactive sputtering of aluminum nitride, silicon nitride, silicon carbide, or nitrides, carbides, or borides of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, or tungsten.
    Type: Grant
    Filed: June 3, 1996
    Date of Patent: May 4, 1999
    Assignee: Tulip Memory Systems, Inc.
    Inventors: Carl W. Nelson, Richard D. Weir
  • Patent number: 5810947
    Abstract: The adhesive strength and hardness of chromium nitride(CrN) film deposited on SKD 61 tool steel was significantly enhanced by a nitriding process on the surface the tool steel before coating with a CrN film. These nitriding processes included nitrocarburing, gas nitriding, and plasma nitriding, respectively. After nitriding, the surface of tool steel was repolishing with grits #600, #1000, #1800 of SiC grinding paper, as well as #1000 grinding paper and diamond paste, respectively. After repolishing, the CrN film was deposited by the cathodic arc ion plating deposition process at low temperatre of 200.degree. C. The present invention was related to the process modification for enhancing the adhesive strength and surface hardness of CrN film deposited on tool steels. This method included a nitriding process and a repolishing followed by the cathodic arc ion plating deposition.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: September 22, 1998
    Assignee: National Science Council
    Inventors: Jiann-Kuo Wu, Fu-Der Lai
  • Patent number: 5785774
    Abstract: An endogenerator is provided in which CO and H.sub.2 are generated as primary products of hydrocarbon oxidation. Noble metal catalysts such as platinum (Pt) and particularly rhodium (Rh), are loaded on a porous ceramic support, of example, an alumina carrier. In the endogenerator reactor little or no CO and H.sub.2 are produced by the slow and energy-intensive reforming reactions and this allows for a compact reactor which operates autothermally without auxiliary heating means, and with high space velocities wherein space velocity is defined as the number of standard cubic feet per hour of output gas per cubic foot of the catalyst carrier. Preferred hydrocarbons are methane or propane, preferred oxidants are nitrogen/oxygen mixtures with from 5% oxygen up to 100% oxygen. The endogenerator of the present invention provides a process and apparatus that generates the required reducing gases CO and H.sub.2 for heat treating applications which require leaner atmospheres and lower carbon potentials.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: July 28, 1998
    Assignee: Praxair Technology, Inc.
    Inventors: Jaak Stefaan Van Den Sype, Alan Russell Barlow
  • Patent number: 5735971
    Abstract: Flawless nitrating layers are obtained during the nitro-carburizing of components made from steels which form passive layers in salt baths if these components are first pre-treated in an oxidizing salt melt at 300.degree. to 500.degree. C. prior to the nitro-carburizing process.
    Type: Grant
    Filed: November 28, 1995
    Date of Patent: April 7, 1998
    Assignee: Durferrit GmbH Thermotechnik
    Inventors: Georg Wahl, Rainer Willing-Lepenies
  • Patent number: 5735375
    Abstract: An electromagnetically actuated friction clutch includes a rotatably driven input gear. A rotatable armature is connected to the input gear and includes a friction face and nitrocarburized outer surfaces. A pole piece has a pole face for engaging the friction face of the armature and nitrocarburized outer surfaces. An electromagnet generates an electromagnetic field to shift the armature from a disengaged position to an engaged position wherein the friction face of the armature and the pole face of the pole piece are frictionally engaged. An output shaft is driven by the input gear when the armature is in the engaged position. The nitrocarburized outer surfaces of the armature and the pole piece resist wear, while interior portions of the armature and pole piece direct magnetic flux flow along a desired path.
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: April 7, 1998
    Assignee: Dana Corporation
    Inventors: Dwight E. Booth, David C. Gustin, Paul A. Larson, Robert A. Olsen
  • Patent number: 5714015
    Abstract: A nitrocarburization treatment for steel components, such as steel balls or ball bearings is disclosed. In the process, the balls are treated in a nitrocarburizing environment and then reoriented, either inside or outside of that environment to form an epsilon iron nitride layer having some thickness over the entire surface of the ball and no bare spots. The reorientation process minimizes superficial metal flow at the surface of the balls and achieves consistent corrosion resistance of at least 96 hours in salt fog tests. Further, components that are cooled in a non-oxidizing environment and then reoriented prior to being returned to the nitrocarburizing environment develop a greater porous layer depth, which provides excellent oil retention for tribological applications.
    Type: Grant
    Filed: April 22, 1996
    Date of Patent: February 3, 1998
    Assignee: Frantz Manufacturing
    Inventor: Paul Lentz
  • Patent number: 5707460
    Abstract: Improved corrosion, wear and fatigue resistance is provided for pieces formed of medium alloy, low carbon steel by subjecting the piece to a treatment process which includes a step of carburizing, followed by nitriding. The process is especially useful for producing durable and low-cost steel parts, for example for certain automotive and marine applications, pumps (especially positive displacement pumps), chemical or food processing equipment, power tools, and the like. The blade-carrying reciprocating shaft for a reciprocating power saw is a specific example.
    Type: Grant
    Filed: July 11, 1995
    Date of Patent: January 13, 1998
    Assignee: Porter-Cable Corporation
    Inventor: Bimal K. Chaterjee
  • Patent number: 5702540
    Abstract: In order to keep down soot production and to enable every part of the workpiece, including deep concavities to be uniformly carburized by vacuum carburizing, and to enable decreases in the quantities of gas and heat employed, carburizing treatment is performed in the heating chamber 2 of a vacuum carburizing furnace 1 with workpieces M being heated while acetylene gas is supplied from a carburizing gas source C inside the heating chamber 2, and the inside of the heating chamber 2 being evacuated by a vacuum evacuation source V to give a vacuum of .ltoreq.1 kPa.
    Type: Grant
    Filed: March 28, 1996
    Date of Patent: December 30, 1997
    Assignee: JH Corporation
    Inventor: Ken Kubota
  • Patent number: 5669988
    Abstract: Object: Prevention of generation of press marks as well as increase of wear resistance at a corrugation tip portion and thereby providing a corrugating roll having a much improved life.Construction: A manufacturing method of a corrugating roll useful for forming a wave-shaped core paper of corrugated board, characterized in that the corrugating roll is worked to form tooth-shaped corrugation portions on the outer circumference and applying a nitriding treatment or a carbo-nitriding treatment, and then applying to the corrugation portion of the corrugating roll a quenching and tempering treatment, and further forming a wear resistant coating on the surface of the corrugation portion.
    Type: Grant
    Filed: August 9, 1995
    Date of Patent: September 23, 1997
    Assignee: Mitsubishi Jukogyo Kabushiki Kaisha
    Inventors: Hiroyuki Takenaka, Yorishige Tosaka, Yasunobu Sahara, Yoshiaki Maruyama, Hidenori Yamane, Akio Izuwa
  • Patent number: 5580397
    Abstract: A carbide and carbonitride surface treatment method for refractory metals is provided, in steps including, heating a part formed of boron, chromium, hafnium, molybdenum, niobium, tantalum, titanium, tungsten or zirconium, or alloys thereof, in an evacuated chamber and then introducing reaction gases including nitrogen and hydrogen, either in elemental or water vapor form, which react with a source of elemental carbon to form carbon-containing gaseous reactants which then react with the metal part to form the desired surface layer. Apparatus for practicing the method is also provided, in the form of a carbide and carbonitride surface treatment system (10) including a reaction chamber (14), a source of elemental carbon (17), a heating subassembly (20) and a source of reaction gases (23).
    Type: Grant
    Filed: January 26, 1995
    Date of Patent: December 3, 1996
    Assignee: The United States of America as represented by the Department of Energy
    Inventors: Glenn A. Meyer, Marcus A. Schildbach
  • Patent number: 5571341
    Abstract: A process for the thermochemical treatment of thin-walled structural elements made of steel comprising enriching an edge zone of a thin-walled structural element with nitrogen and carbon at 590.degree. to 700.degree. C. to harden the edge zone whereby an intermediate layer (3) is formed in the diffusion zone (2), said intermediate layer comprising 1 to 3% by weight of nitrogen and at most 0.8% by weight of carbon and cooling the said thin-walled structural element under an inert atmosphere at a rate of 50.degree. to 100.degree. C. per minute to room temperature to form a nitrogen austenite and/or braunite phase between the connection layer (1) and the basic structure (4) with increased fatigue strength.
    Type: Grant
    Filed: March 13, 1995
    Date of Patent: November 5, 1996
    Assignee: Ina Walzlager Schaeffler KG
    Inventor: Dieter Jackel
  • Patent number: 5534083
    Abstract: A method for processing a reinforcing stainless steel wire--aluminum alloy composite structure, includes carbon nitriding the surface of a stainless steel wire and coating the treated stainless steel wire with an aluminum alloy, and a product thereof.
    Type: Grant
    Filed: May 4, 1995
    Date of Patent: July 9, 1996
    Assignee: Hyundai Motor Co., Ltd.
    Inventors: Bum-Goo Chung, Myung-Ho Kim
  • Patent number: 5498299
    Abstract: The surface oxidation under carburization temperatures of steels during the carburization with carbon-containing gas mixtures is avoided by heating the steels to the carburization temperature under a nitrogen/hydrogen mixture or pure hydrogen. For carburization, these gases are replaced by a carbon-containing gas mixture whose oxygen activity is smaller than that required for the formation of manganese(II) oxide or chromium(III) oxide.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: March 12, 1996
    Assignee: Messer Griesheim GmbH
    Inventor: Hans-Peter Schmidt
  • Patent number: 5456766
    Abstract: Process for carbonitriding a steel comprising:0.75-1.1% by weight of C;up to 1.0% by weight of Si;less than 0.015% by weight of P;up to 0.5% by weight of Mo;up to 1.2% by weight of Mn;0.5-2% by weight of Cr,the remainder being Fe,by exposing it at elevated temperatures to an atmosphere comprising at least carbon monoxide, hydrogen, nitrogen and added ammonia. This is carried out by exposing it, between 780.degree. and 900.degree. C., for from 1 to 10 hours, to an atmosphere comprising at least carbon monoxide, hydrogen and ammonia with a carbon activity between 0.90 and 1.10 and a nitrogen potential between 0.10 and 0.60% N.
    Type: Grant
    Filed: May 23, 1994
    Date of Patent: October 10, 1995
    Assignee: SKF Industrial Trading & Development Company, B.V.
    Inventors: Johan M. Beswick, Adian M. Kerrigan, Jan T. Slycke, Terence T. Vollmer
  • Patent number: 5417774
    Abstract: A process for producing low-cost atmospheres suitable for annealing, brazing, and sintering ferrous and non-ferrous metals and alloys, neutral hardening low, medium, and high carbon steels, sintering ceramic powders, and sealing glass to metal from non-cryogenically produced nitrogen containing up to 5% residual oxygen is disclosed. According to the process, suitable atmospheres are produced by 1) pre-heating the non-cryogenically produced nitrogen stream containing residual oxygen to a desired temperature, 2) mixing it with more than a stoichiometric amount a hydrocarbon gas, 3) passing it through a reactor packed with a platinum group of metal catalyst to reduce the residual oxygen to very low levels and convert it to a mixture of moisture and carbon dioxide, and 4) introducing the reactor effluent stream into the heating zone of a furnace and converting in-situ a portion of both moisture and carbon dioxide with a hydrocarbon gas to a mixture of carbon monoxide and hydrogen.
    Type: Grant
    Filed: December 22, 1992
    Date of Patent: May 23, 1995
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Diwakar Garg, Brian B. Bonner, Donald P. Eichelberger, Kerry R. Berger
  • Patent number: 5389161
    Abstract: After preliminary treatment of their surfaces, the parts are brought into contact within a solution containing, essentially, protons, phosphate anions and cations chosen from Ca.sup.2+, Sn.sup.2+ and Mn.sup.2+. The preliminary treatment results in the formation, on the surface, of a layer that comprises, per 1000 atoms, at least 150 atoms of free iron and from 5 to 150 atoms of sulphur, and has a porosity defined by an actual surface area to macroscopic surface area ratio of at least 20. According to an embodiment, these surface characteristics are obtained by nitriding in a bath of molten salts containing sulphur-containing species. According to a second embodiment, these surface characteristics are obtained by nitriding in a bath of molten salts followed by a conventional sulphiding operation. According to a third embodiment, these surface characteristics are obtained by depositing metal, followed by a conventional sulphiding operation.
    Type: Grant
    Filed: February 8, 1993
    Date of Patent: February 14, 1995
    Assignee: Centre Stephanois de Recherches Mecaniques Hydromecanique et Frottement
    Inventors: Joseph Wawra, Jean-Marc Poirson
  • Patent number: 5348592
    Abstract: An improved method for producing substantially moisture- and oxygen-free, nitrogen-hydrogen atmospheres suitable for annealing, hardening, brazing, and sintering ferrous and non-ferrous metals and alloys is disclosed. According to the disclosed method, suitable nitrogen-hydrogen atmosphere is produced by 1) generating a nitrogen stream containing about 0.1 to 5% residual oxygen by a known non-cryogenic air separation technique, 2) mixing it with a pre-determined but more than stoichiometric amount of hydrogen required to convert residual oxygen to moisture, 3) converting residual oxygen to moisture by reaction with hydrogen in a catalytic reactor, 4) cooling the reactor effluent stream, and 5) removing moisture from it in a regenerative sorbent dryer.
    Type: Grant
    Filed: February 1, 1993
    Date of Patent: September 20, 1994
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Diwakar Garg, Brian B. Bonner, Paul T. Kilhefner, Paul A. Mattiola, David L. Mitchell
  • Patent number: 5340412
    Abstract: An austenitic stainless steel screw having a nitride hard layer on its surface to prevent corrosion on parts of the screw such as a screw head which is in contact with the environment by removing a portion of the nitride hard layer to expose austenitic stainless steel base. By contrast, in the thread part and the like of the screw, the nitride hard layer is retained to improve the hardness and the tapping functions of the screw. In the method for manufacturing, the austenitic stainless steel screw is exposed to a fluorine-or fluoride-containing gas atmosphere prior to nitriding to form a fluoride film on its surface and then is nitrided in that state. Accordingly, the so formed nitride hard layer becomes uniform and deep to obtain an austenitic stainless steel screw having excellent surface properties.
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: August 23, 1994
    Assignee: Daidousanso Co., Ltd.
    Inventors: Akira Yoshino, Massaki Tahara, Haruo Senbokuya, Kenzo Kitano, Teruo Minato
  • Patent number: 5298090
    Abstract: A process for producing low-cost atmospheres suitable for annealing, brazing, and sintering non-ferrous metals and alloys from non-cryogenically produced nitrogen containing up to 5%, residual oxygen is disclosed. According to the process, suitable atmospheres are produced by 1) pre-heating the non-cryogenically produced nitrogen stream containing residual oxygen to a desired temperature, 2) mixing it with more than a stoichiometric amount a hydrocarbon gas, 3) passing it through a reactor packed with a platinum group of metal catalyst to reduce the residual oxygen to very low levels and convert it to a mixture of moisture and carbon dioxide, and 4) using the reactor effluent stream for annealing, brazing, and sintering non-ferrous metals and alloys in a furnace.
    Type: Grant
    Filed: December 22, 1992
    Date of Patent: March 29, 1994
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Diwakar Garg, Brian B. Bonner, Donald P. Eichelberger, Kerry R. Berger
  • Patent number: 5288340
    Abstract: In order to improve the corrosion resistance, carbonitrided components formed of ferrous material are treated, after an oxidation treatment, with a solution of a heat hardenable organic synthetic resin and heat-treated at 80.degree. to 200.degree. C.
    Type: Grant
    Filed: August 16, 1991
    Date of Patent: February 22, 1994
    Assignee: Degussa Aktiengesellschaft
    Inventors: Ulrich Christ, Helmut Kunst, Georg Wahl
  • Patent number: 5284526
    Abstract: An integrated two-step process for producing low-cost atmospheres suitable for annealing ferrous and non-ferrous metals and alloys, brazing metals, sealing glass to metals, and sintering metal and ceramic powders in continuous furnaces from non-cryogenically produced nitrogen containing up to 3% residual oxygen is disclosed. The residual oxygen present in non-cryogenically produced nitrogen is converted to moisture by mixing it hydrogen and passing the mixture through a reactor packed with a platinum group catalyst in the first step of the process. The reactor effluent stream containing a mixture of nitrogen, unreacted hydrogen, and moisture is mixed with a predetermined amount of a hydrocarbon gas and introduced into the heating zone of a continuous furnace in the second step of the process to 1) convert moisture to a mixture of carbon monoxide and hydrogen by reaction with the hydrocarbon gas via water gas shift reaction and 2) produce atmospheres in-situ suitable for heat treating.
    Type: Grant
    Filed: December 22, 1992
    Date of Patent: February 8, 1994
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Diwakar Garg, Brian B. Bonner, Donald P. Eichelberger
  • Patent number: 5254183
    Abstract: Elements for use as protecting fuel contacting surfaces of a gas turbine engine are protected from carbon deposition by heating the element in a nitrogen containing atmosphere for sufficient time to cause penetration and absorption of nitrogen into the grain boundaries of the alloy surface, which acts as a barrier between the hydrocarbon fuel and the catalytic elements in the surfaces.
    Type: Grant
    Filed: December 20, 1991
    Date of Patent: October 19, 1993
    Assignee: United Techynologies Corporation
    Inventors: John A. Harris, III, William H. Edwards, III, Edward S. Smith
  • Patent number: 5252146
    Abstract: A process for nitrocarburizing ferrous materials, and the product thereof is described. Material to be treated is packed in a container with a triazine polymer, preferably melone, melem or melam and heated to 500.degree.-900.degree. C. for up to 120 minutes. After treatment the material can be oil quenched to produce a product having a diffusion layer and or a relatively thick hard nitrocarburized (outer) layer which is 40-200 3/4m thick and has a hardness in the range HV 400-1500.
    Type: Grant
    Filed: August 24, 1992
    Date of Patent: October 12, 1993
    Assignee: Queen's University
    Inventors: Lianyu Wen, Jiwei Shi, Reginald W. Smith