Tungsten Carbide Patents (Class 419/18)
  • Patent number: 6521174
    Abstract: The residual stresses that are experienced in polycrystalline diamond cutters, which lead to cutter failure, can be effectively modified by selectively thinning the carbid substrate subsequent to a high-temperature, high-pressure (sinter) processing, by selectively varying the material constituents of the carbide substrate, by subjecting the PDC cutter to an annealing process during sintering, by subjecting the formed PDC cutter to a post-process stress relief anneal, or by a combination of those means.
    Type: Grant
    Filed: November 21, 2000
    Date of Patent: February 18, 2003
    Assignee: Baker Hughes Incorporated
    Inventors: Trent N. Butcher, Ralph M. Horton, Stephen R. Jurewicz, Danny E. Scott, Redd H. Smith
  • Publication number: 20030000339
    Abstract: The invention relates to sintered particles for use in wear applications and to a process for producing the sintered particles. The particles are of substantially spheroidal shape, have a grain size of 20 to 180 &mgr;m and have a predominantly closed porosity or are free of pores. The process for producing such particles starts from a powder material with a partially porous internal structure, which is introduced into a furnace and sintered at a temperature at which the material of the metallic binder adopts a pasty state while applying pressure to reduce the pore content of the starting material.
    Type: Application
    Filed: June 17, 2002
    Publication date: January 2, 2003
    Applicant: WOKA Schweisstechnik GmbH
    Inventors: Eberhard G. Findeisen, Richard F. Moll, Siegmund Kremmer
  • Patent number: 6500226
    Abstract: This disclosure features a process of making a two part drill bit insert, namely, a body portion of hard particles such as tungsten carbide particles mixed in an alloy binding the particles. The alloy preferably comprises 6% cobalt with amounts up to about 10% permitted. The body is sintered into a solid member, and also joined to a PDC crown covering the end. The crown is essentially free of cobalt. The process sinters the crown and body while preserving the body and crown cobalt differences.
    Type: Grant
    Filed: April 24, 2000
    Date of Patent: December 31, 2002
    Assignee: Dennis Tool Company
    Inventor: Mahlon D. Dennis
  • Publication number: 20020155312
    Abstract: A coated body that has a substrate of tungsten, carbon, and cobalt, and wherein the substrate presents a surface. Eta phase is present at the surface of the substrate. Fibrous tungsten carbide grains are present at the surface of the substrate. The surface of the substrate has a surface roughness, Ra, of greater than about 12 microinches. A coating layer is on the surface of the substrate.
    Type: Application
    Filed: March 22, 2002
    Publication date: October 24, 2002
    Inventors: Alfred S. Gates, Aharon Inspektor
  • Publication number: 20020148326
    Abstract: There is now provided a cemented carbide grade for rock excavation purposes with 88-96 weight % WC, preferably 91-95% weight % WC, with a binder phase consisting of only cobalt or cobalt and nickel, with a maximum of 25% of the binder being Ni, possibly with small additions of rare earth metals, such as Ce and Y, up to a maximum of 2% of the total cemented carbide. The WC grains are rounded because of the process of coating the WC with cobalt, and not recrystallized or showing grain growth or very sharp cornered grains like conventionally milled WC, thus giving the bodies surprisingly high thermal conductivity. The average grain size should be from 8-30 &mgr;m, preferably from 12-20 &mgr;m. The maximum grain size does not exceed 2 times the average value and no more than 2% of the grains found in the structure are less than half of the average grain size.
    Type: Application
    Filed: April 2, 2002
    Publication date: October 17, 2002
    Inventors: Jan Akerman, Thomas Ericson
  • Patent number: 6461401
    Abstract: A composite structural metal use, for example, in drill bit bodies is disclosed. The metal includes powdered tungsten carbide, and binder metal consisting of a composition by weight of manganese in a range of about zero to 25 percent, nickel in a range of about zero to 15 percent, zinc in a range of about 3 to 20 percent, tin in a range of more than 1 percent to about 10 percent, and copper making up about 24 to 96 percent by weight of the composition. In one embodiment, the composition includes about 6 to 7 percent tin therein. In another embodiment, the composition includes about 0-6 percent by weight of cobalt.
    Type: Grant
    Filed: August 10, 2000
    Date of Patent: October 8, 2002
    Assignee: Smith International, Inc.
    Inventors: Kumar T. Kembaiyan, Thomas W. Oldham
  • Patent number: 6454027
    Abstract: Polycrystalline diamond (PCD) carbide composites of this invention have a microstructure comprising a plurality of granules formed from PCD, polycrystalline cubic boron nitride, or mixture thereof, that are distributed within a substantially continuous second matrix region that substantially surrounds the granules and that is formed from a cermet material. In an example embodiment, the granules are polycrystalline diamond and the cermet material is cemented tungsten carbide. PCD carbide composites of this invention display improved properties of fracture toughness and chipping resistance, without substantially compromising wear resistance, when compared to conventional pure PCD materials.
    Type: Grant
    Filed: March 9, 2000
    Date of Patent: September 24, 2002
    Assignee: Smith International, Inc.
    Inventors: Zhigang Fang, Anthony Griffo, Brian A. White, Stewart Middlemiss, Ron K. Eyre
  • Patent number: 6428596
    Abstract: A multiplex powder composite for use in a cored wire electrode to be deployed in a thermal spray or welding apparatus. The composite comprises micron-sized particles and sub-micron-sized particles, including nano-scale particles, the particles mechanically cooperating to promote smooth powder flow, which facilitates compaction of the cored wire electrode.
    Type: Grant
    Filed: November 13, 2000
    Date of Patent: August 6, 2002
    Assignee: Concept Alloys, L.L.C.
    Inventors: David John Urevich, Joseph Paul Hughes
  • Patent number: 6413293
    Abstract: The present invention relates to a method of making ultrafine WC—Co alloys from a well dispersed mixture of fine and non-agglomerated WC and Co powders, wherein the Co powders have a narrow grain size distribution wherein at least 80% of the grains have sizes in the interval x+0.2x with the interval of variation of 0.4x is not smaller than 0.1 um, and a carbon content of approximately the amount necessary to provide eta phase formation.
    Type: Grant
    Filed: August 16, 2000
    Date of Patent: July 2, 2002
    Assignee: Sandvik AB
    Inventors: Alistair Grearson, John Aucote, Michael John Carpenter
  • Patent number: 6402802
    Abstract: Embodiments include a method for fabricating a nanograined component from a nanograined powder composition. A compact is formed from the nanograined powder composition and sufficient heat is applied to the compact to generate at least one exothermic reaction while the compact is at a temperature lower than its eutectic temperature. Pressure is applied to the powder compact during the heating operation to consolidate the powder compact. The application of heat and pressure are controlled to inhibit grain growth and form a component having a nanograined microstructure that is at least 98 percent dense at a temperature lower than the eutectic temperature.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: June 11, 2002
    Assignee: The Penn State Research Foundation
    Inventor: Ram B. Bhagat
  • Patent number: 6399018
    Abstract: Solid objects are made by means of a novel multi-step forming, debinding, sintering and infiltrating process, using a metal-ceramic composition. In this process, the mixture is held for a period of time to degas and settle the powdered material from a liquid binder. The packed geometry is then heated to above the melting temperature of the binder to remove the binder portion of the solid geometry. Upon removal of the binder the binder-free solid geometry is raised to a temperature where the metal pre-sinters together into a three-dimensional rigid matrix with interconnected porosity to form a solid precursor. The porous matrix includes the particulate ceramic material and a first metal, which are at least partially sintered. A molten second metal is then introduced to the fill the porous matrix and form an infiltrated matrix.
    Type: Grant
    Filed: April 16, 1999
    Date of Patent: June 4, 2002
    Assignee: The Penn State Research Foundation
    Inventors: Randall M. German, Timothy J. Weaver, Julian A. Thomas, Sundar V. Atre, Anthony Griffo
  • Patent number: 6375706
    Abstract: A composition for drill bit bodies and a method for making drill bits from the composition are disclosed. The composition includes powdered tungsten carbide, and binder metal consisting of a composition by weight of manganese in a range of about zero to 25 percent, nickel in a range of about zero to 15 percent, zinc in a range of about 3 to 20 percent, tin in a range of more than 1 percent to about 10 percent, and copper making up the remainder by weight of the composition. In one embodiment, the composition includes about 6 to 7 percent tin therein. The composition is heated to at least the infiltration temperature in a mold for form a drill bit body.
    Type: Grant
    Filed: January 11, 2001
    Date of Patent: April 23, 2002
    Assignee: Smith International, Inc.
    Inventors: Kuttaripalayam T. Kembaiyan, Thomas W. Oldham
  • Publication number: 20020031440
    Abstract: A dense cemented carbide product is described. The product is manufactured from WC with a grain size between 0.1 and 0.4 ¼ m, fine grain size cobalt and ruthenium powders. The product is used in PCB machining operations where the addition of 10-25% Ru to the binder phase offers up to 25% wear resistant incrases and up to 100% increase in chipping resistance in PCB routing compared to conventional materials (6% cobalt and 0.4 ¼ m grain size).
    Type: Application
    Filed: May 15, 2000
    Publication date: March 14, 2002
    Inventors: ALISTAIR GREARSON, JOHN AUCOTE
  • Patent number: 6336951
    Abstract: An improved method of making submicron cemented carbide bodies include wet milling powders of WC and Co and grain growth inhibitors to a slurry, drying the slurry to a powder, uniaxial pressing of the powder to form bodies of a desired shape, and sintering. WC powder is provided with an FSSS grain size, dwc, of less than 1 &mgr;m and a Co powder with an FSSS grain size, dco, such that the ratio dwc/dco is 0.75-1.5.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: January 8, 2002
    Assignee: Seco Tools AB
    Inventors: Jan Qvick, Bo Jansson
  • Patent number: 6299658
    Abstract: In a cemented carbide, at least one compound 3 including a carbide, a nitride or carbo-nitride of at least one component selected from IVa, Va and VIa group elements or a solid solution thereof exists in at least some WC crystal grains 1. Preferably the compound 3 is in the form of compound grains 3 comprising a carbide, a nitride or a carbo-nitride of Ti, Zr, Hf or W or a solid solution thereof, having an average grain diameter smaller than 0.3 &mgr;m. The compound grains make up at most 10% of the cross-sectional area of the WC crystal grains that contain the compound grains, while at least 10% of the total cross-sectional area of the cemented carbide is made up of such WC crystal grains that contain the compound grains.
    Type: Grant
    Filed: July 23, 1998
    Date of Patent: October 9, 2001
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hideki Moriguchi, Akihiko Ikegaya
  • Patent number: 6294129
    Abstract: The present invention relates to a method of making a cemented carbide body with a bimodal grain size distribution by powder metallurgical methods including wet mixing, without milling, of WC-powders with different grain size distributions with binder metal and pressing agent, drying, pressing and sintering. The grains of the WC-powders are classified in at least two groups, a group of smaller grains and a group of larger grains. According to the method of the present invention, the grains of the group of smaller grains are precoated with a growth inhibitor with or without binder metal.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: September 25, 2001
    Assignee: Sandvik AB
    Inventor: Mats Waldenström
  • Patent number: 6287360
    Abstract: A new composition for making an improved high-strength matrix body and methods of making the matrix body are disclosed. The new composition includes large-grain carburized tungsten carbide, an infiltration binder, and optionally cast tungsten carbide. The high-strength matrix body is formed from the new composition by an infiltration process. Suitable infiltration binders include all transition metals and all main group metals. To obtain optimal physical properties, large-grain carburized tungsten carbide is mixed with cast tungsten carbide and Ni powder before infiltration. The high-strength matrix body has improved braze strength. Such matrix bodies are suitable for manufacturing bit bodies for PDC drill bits and other earth-boring devices.
    Type: Grant
    Filed: September 18, 1998
    Date of Patent: September 11, 2001
    Assignee: Smith International, Inc.
    Inventors: Kuttaripalayam T. Kembaiyan, Thomas W. Oldham
  • Patent number: 6261329
    Abstract: A diamond sintered body having high wear resistance, chipping resistance, shock resistance and thermal conductivity is provided. The diamond sintered body includes sintered diamond particles and a sintering aid as the remainder. The content of the sintered diamond particles is at least 80% by volume and less than 99% by volume. The sintered diamond particles have a particle size in the range from at least 0.1 &mgr;m to at most 70 &mgr;m. The sintered diamond particles next to each other are directly bonded. The sintering aid includes at least one kind selected from tungsten, iron, cobalt and nickel. The percentage of the tungsten in the sintered body is in the range from at least 0.01% by weight to at most 8% by weight.
    Type: Grant
    Filed: August 10, 1999
    Date of Patent: July 17, 2001
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yasunobu Ogata, Satoru Kukino, Yasuyuki Kanada, Junichi Shiraishi, Tetsuo Nakai
  • Patent number: 6258147
    Abstract: The present invention relates to a sintered cemented carbide consisting of 50 to 90 wt-% submicron WC in a hardenable binder phase. The binder phase comprises, in addition to Fe, 10-60 wt-% Co, <10 wt-% Ni, 0.2-0.8 wt-% C, Cr, W, Mo and/or V in amounts satisfying the relations 2xC<xW+xCr+xMo+xV<2.5xC where x denotes mol fraction elements in the binder phase and the following relation for the total Cr content 0.03<wt-% Cr/(100-wt-% WC)<0.05 In addition, the binder phase consists of martensite with a fine dispersion, a few percent, of coherent carbides, preferably of M2C type, with a size of the order of 10 nm.
    Type: Grant
    Filed: January 19, 2000
    Date of Patent: July 10, 2001
    Assignee: Seco Tools AB
    Inventors: Bo Jansson, Jan Qvick
  • Patent number: 6254658
    Abstract: To provide a cemented carbide cutting tool having high chipping resistance. In a cutting tool made of a cemented carbide alloy comprising 8 to 13 percent by weight of Co; the Co based alloy containing W and C components as constituents for forming a dispersing phase, a V component, and an optional Cr component, and forming a binding phase; the residual dispersing phase having an average particle diameter of 1 &mgr;m or less; the alloy further containing 72 to 90 percent by area of WC according to measurement of an electron microscopic texture and fine (V,W)C or fine (V,Cr,W)C; each of the contents of the V and Cr components being 0.1 to 2 percent by weight of the total; the tungsten carbide as a constituent of the dispersing phase has a texture in which ultra-fine particles having a particle diameter of 100 nm or less of the Co-based cemented carbide alloy are dispersed in a tungsten carbide matrix.
    Type: Grant
    Filed: February 24, 1999
    Date of Patent: July 3, 2001
    Assignee: Mitsubishi Materials Corporation
    Inventors: Toshiyuki Taniuchi, Kazuki Okada, Kazuhiro Akiyama
  • Patent number: 6245288
    Abstract: A pressable powder is formed by a method comprising [I] mixing, in essentially deoxygenated water, [A] a first powder selected from the group consisting of a transition metal carbide and transition metal with [B] an additional component selected from the group consisting of (i) a second powder comprised of a transition metal carbide, transition metal or mixture thereof; (ii) an organic binder and (iii) combination thereof and [II] drying the mixed mixture to form the pressable powder, wherein the second powder is chemically different than the first powder. The pressable powder may then be formed into a shaped part and subsequently densified into a densified part, such as a cemented tungsten carbide.
    Type: Grant
    Filed: January 31, 2000
    Date of Patent: June 12, 2001
    Assignee: OMG Americas, Inc.
    Inventor: Daniel F. Carroll
  • Patent number: 6228139
    Abstract: The present invention relates to a method of making a WC—Co-based cemented carbide with a sintered mean WC-grain size in the range 0.4-1.6 &mgr;m. the cemented carbide is produced from well deagglomerated or easy to deagglomerate WC powder with round morphology, a Co powder also well deagglomerated or easy to deagglomerate and with a grain size equal to or smaller than the WC grain size and grain growth inhibitors. According to the invention the metal part of the grain growth inhibitors is added as part of the binder phase i.e., is included in the Co powder and alloyed therewith.
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: May 8, 2001
    Assignee: Sandvik AB
    Inventor: Rolf Oskarsson
  • Patent number: 6214287
    Abstract: The present invention relates to a method of making a cemented carbide comprising WC, 6-12 wt. % Co and 0.1-0.7 wt. % Cr, wherein the WC-grains are coated with Cr prior to mixing and no milling takes place during the mixing step. As a result a cemented carbide with improved properties is obtained.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: April 10, 2001
    Assignee: Sandvik AB
    Inventor: Mats Waldenström
  • Patent number: 6200524
    Abstract: The present invention discloses a method of manufacturing a face seal wherein an annular groove on the face seal substrate is filled with a mixture of a metal binder and refractory metal carbide and pressed. A second metal binder layer is then placed upon the pressed mixture and a second pressing step is performed to form an integral green body of the first pressed mixture and the second metal binder layer. The integral green body is then heated to consolidate and adhere the green body to the substrate.
    Type: Grant
    Filed: April 29, 1999
    Date of Patent: March 13, 2001
    Assignee: Mech Coating Ltd.
    Inventors: Yefim Griskin, Natalya Griskin
  • Patent number: 6197084
    Abstract: Thermal fatigue and shock resistant materials have been disclosed. Such materials have a thermal conductivity exceeding a minimal value as determined by Kmim=0.00102X2−0.03076X+0.5464, where Kmin is minimal thermal conductivity in the units of cal/cm·s·°K, and X is cobalt weight percentage. Cemented tungsten carbide with coarse tungsten carbide grains and a low cobalt content meet this criterion. The thermal conductivity of this type of cemented tungsten carbide may be further enhanced by using tungsten carbide of coarser grains and higher purity. By adjusting the tungsten carbide grain size and the cobalt content, a desired toughness and hardness may be achieved while still maintaining a relatively high thermal conductivity. Such materials have applications in forming inserts and other cutting elements.
    Type: Grant
    Filed: January 15, 1999
    Date of Patent: March 6, 2001
    Assignee: Smith International, Inc.
    Inventor: Dah-Ben Liang
  • Patent number: 6183688
    Abstract: A cutting member is manufactured by forming a mixture of cemented carbide and a bearer, and heating the mixture. Then, the heated mixture is injected into a mold for forming a body having a cutting edge in a front surface thereof, a flushing channel extending therethrough, and a rearwardly open blind hold formed centrally in a rear surface thereof. The body is then removed from the mold.
    Type: Grant
    Filed: July 7, 1999
    Date of Patent: February 6, 2001
    Assignee: Seco Tools AB
    Inventors: Ronny Karlsson, Johnny Bruhn
  • Patent number: 6183687
    Abstract: A method of heat treating a sintered body having an exposed surface which has the steps of: providing a sintered body comprised of a hard carbide and a binder, the binder being present in the sintered body at a first binder level and the hard carbide in the sintered body being of a first grain size; placing granules of a sacrificial sintered material in contact with at least one portion of the exposed surface of the sintered body, the sacrificial sintered material comprised of the hard carbide and the binder, the binder being present in the sacrificial sintered material at a second binder level and the hard carbide in the sacrificial sintered material being of a second grain size; and heat treating the sintered body and sacrificial sintered material so as to change the binder content in a surface region of the sintered body.
    Type: Grant
    Filed: August 11, 1995
    Date of Patent: February 6, 2001
    Assignee: Kennametal Inc.
    Inventor: Mark S. Greenfield
  • Patent number: 6090343
    Abstract: A method for fabricating a triphasic composite such as a WC/Co/diamond composite with a high volume fraction of diamond in a WC/Co matrix. The method involves sintering of a WC/Co powder compact to develop a porous preform, which displays some rigidity and strength, infiltrating the porous preform with a controlled distribution of carbon, and high pressure/high temperature treatment of the carbon-containing WC/Co preform to transform the carbon to diamond. The distribution of diamond in the composite can be functionally graded to provide a WC/Co core and a diamond-enriched surface, wherein all three phases form an interconnected structure in three dimensions. Such a tricontinuous structure combines high strength and toughness with superior wear resistance, making it attractive for applications in machine tools and drill bits.
    Type: Grant
    Filed: March 25, 1998
    Date of Patent: July 18, 2000
    Assignee: Rutgers University
    Inventors: Bernard H. Kear, Rajendra K. Sadangi, Larry E. McCandlish, Oleg Voronov
  • Patent number: 6024896
    Abstract: The contacts material of the present invention is contacts material including silver-tungsten carbide alloy containing 55-70 weight % of tungsten carbide (WC) of mean particle size 0.1-6 .mu.m wherein is included 0.005-0.2 weight % of carbon in an undissolved state or non-compound state whose equivalent diameter is 0.01-5 .mu.m.The present invention enables the current interruption characteristics of contacts material to be improved.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: February 15, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsutomu Okutomi, Atsushi Yamamoto, Tsuneyo Seki, Tadaaki Sekiguchi
  • Patent number: 6019813
    Abstract: The present invention relates to cobalt metal agglomerates consisting of peanut-shaped primary particles with average particle sizes in the range from 0.5 to 2 .mu.m, to a process for the production thereof and to the use thereof.
    Type: Grant
    Filed: April 24, 1998
    Date of Patent: February 1, 2000
    Assignee: H.C. Starck GmbH & Co. KG
    Inventors: Astrid Gorge, Katrin Plaga, Armin Olbrich, Dirk Naumann, Wilfried Gutknecht, Josef Schmoll
  • Patent number: 6015447
    Abstract: The present invention relates to cobalt metal agglomerates consisting of peanut-shaped primary particles, to a process for the production thereof and to the use thereof.
    Type: Grant
    Filed: November 21, 1997
    Date of Patent: January 18, 2000
    Assignee: H.C. Starck GmbH & Co. KG
    Inventors: Astrid Gorge, Juliane Meese-Marktscheffel, Dirk Naumann, Armin Olbrich, Frank Schrumpf
  • Patent number: 5993506
    Abstract: Disclosed are a plate-crystalline tungsten carbide-containing hard alloy which comprises 4 to 40% by volume of a binder phase containing at least one of iron group metals selected from Co, Ni and Fe as a main component; and the balance of a hard phase comprising tungsten carbide alone, or tungsten carbide and 50% by volume or less of a compound with a cubic structure selected from at least one of carbide and nitride of the 4a (Ti, Zr and Hf), 5a (V, Nb and Ta) or 6a (Cr, Mo and W) group element of the periodic table and mutual solid solutions thereof, and inevitable impurities,wherein when peak intensities at a (001) face and a (101) face in X-ray diffraction using K.alpha. rays with Cu being a target are represented by h(001) and h(101), respectively, the tungsten carbide satisfies h(001)/h(101) .gtoreq.0.50, a composition for forming a plate-crystalline tungsten carbide, and a process for preparing the plate-crystalline tungsten carbide-containing hard alloy.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: November 30, 1999
    Assignee: Toshiba Tungaloy Co., Ltd.
    Inventors: Masaki Kobayashi, Kozo Kitamura, Satoshi Kinoshita
  • Patent number: 5993730
    Abstract: One or more organic or inorganic metal salts or compounds of at least one of the groups IV, V and VI of the periodic system, particularly V, Cr, Mo and W, optionally together with one or more organic iron group metal salts, are dissolved in at least one polar solvent and complex bound with at least one complex former comprising functional groups in the form of OH or NR.sub.3, (R=H or alkyl). Hard constituent powder and optionally soluble carbon source are added to the solution. The solvent is evaporated and the remaining powder is heat treated in an inert and/or reducing atmosphere. As a result, coated hard constituent powder is obtained, which after addition of a pressing agent and optionally with other coated hard constituent powders and/or carbon to obtain the desired composition, can be compacted and sintered according to standard practice.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: November 30, 1999
    Assignee: Sandvik AB
    Inventors: Mats Waldenstrom, Rolf Svensson
  • Patent number: 5989731
    Abstract: In a composite material manufactured by connecting a sintered body to a surface of a metal substrate, the connection strength under a high temperature is increased, stress relaxation in the composite material is attained, and the strength, wear resistance and corrosion resistance are improved. The sintered body has a multilayer structure having layers with different compositions, i.e. compositions that vary or differ in a direction perpendicular to the connection surface, and the volume relation between the respective layers of the sintered body and the substrate is (substrate volume.times.0.2).gtoreq.(sintered body volume/number of layers), while the thickness of each layer is at least 0.2 mm and not more than 5 mm.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: November 23, 1999
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yoshifumi Arisawa, Michio Otsuka, Hideki Moriguchi
  • Patent number: 5950064
    Abstract: There is provided a lead-free projectile, such as a bullet or a ballistic shot, formed by liquid phase sintering or liquid phase bonding of a first particulate having a density greater than lead, a second, ductile, particulate having a melting temperature in excess of 400.degree. C. and a binder having a fluidity temperature that is less than the melting temperature of the second particulate. Unlike solid phase sintering that tends to produce articles having a porosity of about 20%, by volume, liquid phase sintering and liquid phase bonding achieve close to 0% porosity. Reducing the porosity level decreases the amount of high density, first particulate, required to achieve a density close to that of lead. Since the high density particulate tends to be the most expensive component of the projectile, this significantly reduces the cost of the projectile. The reduced porosity also allows for an increase in the amount of the second, ductile, component.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: September 7, 1999
    Assignee: Olin Corporation
    Inventors: Peter W. Robinson, Brian Mravic, Derek E. Tyler
  • Patent number: 5922978
    Abstract: A pressable powder is formed by a method comprising mixing, in essentially deoxygenated water, a first powder selected from the group consisting of a transition metal carbide and transition metal with an additional component selected from the group consisting of (i) a second powder comprised of a transition metal carbide, transition metal or mixture thereof; (ii) an organic binder and (iii) combination thereof and drying the mixed mixture to form the pressable powder, wherein the second powder is chemically different than the first powder. The pressable powder may then be formed into a shaped part and subsequently densified into a densified part, such as a cemented tungsten carbide.
    Type: Grant
    Filed: March 27, 1998
    Date of Patent: July 13, 1999
    Assignee: OMG Americas, Inc.
    Inventor: Daniel F. Carroll
  • Patent number: 5918103
    Abstract: Disclosed are a plate-crystalline tungsten carbide-containing hard alloy which comprises 4 to 40% by volume of a binder phase containing at least one of iron group metals selected from Co, Ni and Fe as a main component; and the balance of a hard phase comprising tungsten carbide alone, or tungsten carbide and 50% by volume or less of a compound with a cubic structure selected from at least one of carbide and nitride of the 4a (Ti, Zr and Hf), 5a (V, Nb and Ta) or 6a (Cr, Mo and W) group element of the periodic table and mutual solid solutions thereof, and inevitable impurities,wherein when peak intensities at a (001) face and a (101) face in X-ray diffraction using K.alpha. rays with Cu being a target are represented by h(001) and h(101), respectively, the tungsten carbide satisfies h(001)/h(101).gtoreq.0.50, a composition for forming a plate-crystalline tungsten carbide, and a process for preparing the plate-crystalline tungsten carbide-containing hard alloy.
    Type: Grant
    Filed: August 6, 1996
    Date of Patent: June 29, 1999
    Assignee: Toshiba Tungaloy Co., Ltd.
    Inventors: Masaki Kobayashi, Kozo Kitamura, Satoshi Kinoshita
  • Patent number: 5902942
    Abstract: There is now provided a roll for hot rolling comprising 70-95 weight %, preferably 85-94 weight %, WC in a binder phase consisting of only cobalt or alternatively a Co--Ni--Cr alloy containing 20-35 weight % Ni and up to 10 weight % Cr, possibly with small additions of molybdenum. The WC grains are rounded with an average grain size between 3-10 .mu.m, preferably 4-8 .mu.m. The maximum grain size should not exceed 2 times the average grain size and no more than 2% of the grains be less than half of the average grain size.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: May 11, 1999
    Assignee: Sandvik AB
    Inventors: Carl-Johan Maderud, Thomas Ericson, Udo Fischer
  • Patent number: 5894034
    Abstract: A method of making a hard constituent powder coated with Co and/or Ni in a solution by liquid reduction of the Co and/or Ni from a suitable metal compound with a polyol while keeping the powder in suspension, the polyol functioning both as a solvent and as a reducing agent at the same time. By separating the intermediate solid compound and hard constituent from the suspension before any by-products are formed and reducing the intermediate solid compound in the dry state by H.sub.2 for around 24 hours or by using an excess of about 10 times more moles polyol than moles metal, the polyol can be conserved or reused leading to improved cost efficiency of the process.
    Type: Grant
    Filed: September 12, 1997
    Date of Patent: April 13, 1999
    Assignee: Sandvik AB
    Inventors: Sara Andersson, Muhammed Mamoun
  • Patent number: 5889219
    Abstract: A sintered body having diamond grains dispersed and held in a matrix of cemented carbide or cermet is obtained by direct resistance heating and pressurized sintering. The sintering is performed at a liquid phase generating temperature in a short time, so that the diamond grains are not directly bonded to each other. Thus, a superhard composite member that has excellent hardness and wear resistance can be obtained without employing an ultra high-pressure vessel.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: March 30, 1999
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hideki Moriguchi, Yoshifumi Arisawa, Michio Otsuka
  • Patent number: 5887242
    Abstract: A method of making a hard constituent powder coated with at least one iron group metal, Me, by dissolving and complex binding at least one of Me.sub.n (NO.sub.3).sub.m and Me.sub.n (SO.sub.4).sub.m and other similar Me.sub.n --X.sub.m compounds containing X-groups with low or no carbon content, preferably Me-nitrates, solely or together with one or more metal salts of at least one iron group metal containing organic groups in at least one polar solvent with at least one complex former comprising functional groups in the form of OH or NR.sub.3, (R=H or alkyl). Hard constituent powder is added to the solution. The solvent is evaporated and remaining powder is heat treated in an inert and/or reducing atmosphere. As a result, coated hard constituent powder is obtained which after addition of a pressing agent can be compacted and sintered according to standard practice.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: March 23, 1999
    Assignee: Sandvik AB
    Inventors: Mats Nygren, Gunnar Westin, .ANG.sa Ekstrand
  • Patent number: 5885653
    Abstract: One or more metal salts of at least one of Co, Ni and/or Fe is dissolved/suspended in water. To the solution/suspension is added at least one hard constituent powder to form a slurry. The solvent is evaporated, preferably by spray drying, and the resultant powder is heat treated in a reducing atmosphere. As a result, a coated hard constituent powder is obtained which, after addition of a pressing agent, can be compacted and sintered according to standard practice. In addition to or instead of said salt of Co, Ni and/or Fe, a soluble salt of Mo and/or W can be used.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: March 23, 1999
    Assignee: Sandvik AB
    Inventors: Mats Waldenstrom, Stefan Ederyd, Nicolas Chardon, Henri Pastor
  • Patent number: 5846288
    Abstract: Electrical contact material made from intimate mixtures of silver powder and a powder of a second phase material is shown in which the powder of the second phase material is milled to produce a selected grain distribution of approximately 90% less than 7-10 microns, approximately 50% between 2 and 5 microns and approximately 10% less than 0.8 to 1.0 microns. The powder of the second phase material is added to a silver salt solution, ammonium hydroxide and hydrazine hydrate to form a precipitate of second phase material particles covered with silver. For applications in which the particles need to be free flowing the particles are compacted together without any binder, broken into chunks and milled to provide granules. In one embodiment homogeneously doped tin oxide particles are disclosed in which tin oxide and the oxide of the dopant are dissolved in nitric acid to produce finely dispersed tin oxide and dopant oxide. The oxides are calcined and ground to the selected grain size distribution.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: December 8, 1998
    Assignee: Chemet Corporation
    Inventors: Ernest M. Jost, Kirk McNeilly
  • Patent number: 5773735
    Abstract: A cemented tungsten carbide body having a transition metal binder phase selected from the group consisting of iron, nickel and cobalt is formed, wherein the WC grains have an average WC grain size of at most about 0.5 micrometer in diameter and a maximum WC grain size of at most about 0.8 micrometer in diameter. Also, about 50 percent by volume of the WC grains in the body are angular grains and the body (1) contains an amount of the transition metal ranging from about 3 percent to about 18 percent by weight of the body, (2) is essentially free of grain growth inhibitors and (3) is essentially pore free.
    Type: Grant
    Filed: November 20, 1996
    Date of Patent: June 30, 1998
    Assignee: The Dow Chemical Company
    Inventors: Ellen M. Dubensky, Robert T. Nilsson
  • Patent number: 5762843
    Abstract: Methods for making, methods for using and articles having cermets, preferably cemented carbides and more preferably tungsten carbide, having at least two regions exhibiting at least one property that differs are discussed. Preferably, the cermets further exhibit a portion that is binder rich and which gradually or smoothly transitions to at least a second region. The multiple-region cermets are particularly useful in compressively loaded application wherein a tensile stress or fatigue limit might otherwise be excessive for monolithic articles. The cermets are manufactured by juxtaposing and densifying at least two powder blends having different properties (e.g., differential carbide grain size, differential carbide chemistry, differential binder content, differential binder chemistry, or any combination of the preceding).
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: June 9, 1998
    Assignee: Kennametal Inc.
    Inventors: Ted R. Massa, John S. Van Kirk, Robert R. McNaughton, Jr.
  • Patent number: 5765095
    Abstract: A method for manufacturing a PCD bit by isostatically or mechanically press forming a green on a metallic blank. A metallic blank is vertically suspended into a flexible vessel. Powder metal is mixed with a binder and introduced into the flexible vessel surrounding the lower end of the suspended metallic blank. The vessel is then isostatically or mechanically pressed causing the powder mixture to stick together and to the blank, forming a green on the blank. The blank and green are removed from the vessel and the exposed end of the metallic blank is chucked onto a milling machine and turned for milling the green into the shape of a PCD bit head. After the milling is completed, the green and blank are sintered, hardening the bit head shaped green and strongly bonding it to the metallic blank, forming a PCD bit wherein the hardened green is the bit head while the metallic blank is the bit pin.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: June 9, 1998
    Assignee: Smith International, Inc.
    Inventors: Richard A. Flak, T. H. (Nick) Nichols, Thomas W. Oldham
  • Patent number: 5754935
    Abstract: The present invention provides a vane material having an excellent scuffing resistance in a compressor employing an alternative Freon gas as a cooling medium and a process for the preparation thereof. In accordance with the present invention, a vane material is provided having a structure comprising a base material consisting essentially of 1.0 to 4.5% by weight of carbon, not more than 1.5% by weight of silicon, not more than 1.0% by weight of manganese, 3 to 6% by weight of chromium, not more than 30% of tungsten and/or not more than 20% by weight of molybdenum provided that (W+2Mo) is not more than 45% by weight, 2 to 10% by weight of vanadium and/or niobium, not more than 20% by weight of cobalt, and a balance of iron and inavoidable impurities with additive particles of a carbide and additive particles of a nitride and/or a carbonitride, sintered thereto in an amount of more than 0% to not more than 25% by weight and 2 to 25% by weight based on the total weight of the vane material, respectively.
    Type: Grant
    Filed: June 10, 1994
    Date of Patent: May 19, 1998
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yutaka Kubo, Hideki Nakamura, Norimasa Uchida, Keiji Yamasaki
  • Patent number: 5697042
    Abstract: Methods for making, methods for using and articles comprising cermets, preferably cemented carbides and more preferably tungsten carbide, having at least two regions exhibiting at least one property that differs are discussed. Preferably, the cermets further exhibit uniform or controlled wear to impart a self-sharpening character to an article. The multiple-region cermets are particularly useful in wear applications. The cermets are manufactured by juxtaposing and densifying at least two powder blends having different properties (e.g., differential carbide grain size or differential carbide chemistry or differential binder content or differential binder chemistry or any combination of the preceding).
    Type: Grant
    Filed: December 21, 1995
    Date of Patent: December 9, 1997
    Assignee: Kennametal Inc.
    Inventors: Ted R. Massa, John S. Van Kirk, Edward V. Conley
  • Patent number: 5670726
    Abstract: In order to improve the toughness characteristics of a cermet alloy, while retaining high resistance to wear, a composition is disclosed which contains 30 to 60% by weight of Ti, 5 to 20% by weight of W, 5 to 15% by weight of Ta, in which up to 70% of the Ta can be replaced by Nb, and 5 to 25% by weight of Ni and/or Co binder with more than 80 mole %, relative to the above transition elements of carbon and nitrogen. The composition is prepared by grinding, compressing and sintering a solid, powder-form mixture containing (Ti,W,Ta,Nb)C powder, Ti(C,N) powder, and WC powder, each powder having a particle size <1.5 .mu.m, plus Ni powder and/or Co powder. The mixture includes the following ingredients: (a) (Ti,W,Ta,Nb)C with a mean particle size <1.5 .mu.m, this mixed carbide containing 20 to 50% by weight of TiC, 20 to 40% by weight of WC, and 20 to 40% by weight of (Ta, Nb)C; (b) Ti(C,N), with a mean particle size <1.5 .mu.m and an N/(C+N) ratio <0.7; WC with a mean particle size <1.5 .mu.
    Type: Grant
    Filed: September 1, 1995
    Date of Patent: September 23, 1997
    Assignee: Widia GmbH
    Inventors: Hans Kolaska, Klaus Dreyer
  • Patent number: 5666631
    Abstract: A compacted, single phase or multiphase composite article. Particles for use in the compacted article are produced by providing a precursor compound containing at least one or at least two metals and a coordinating ligand. The compound is heated to remove the coordinating ligand therefrom and increase the surface area thereof. It may then be reacted so that at least one metal forms a metal-containing compound. The particles may be consolidated to form a compacted article, and for this purpose may be used in combination with graphite or diamonds. The metal-containing compound may be a nonmetallic compound including carbides, nitrides and carbonitrides of a refractory metal, such as tungsten. The metal-containing compound may be dispersed in a metal matrix, such as iron, nickel or cobalt. The dispersed nonmetallic compound particles are no larger than about 0.1 micron in particle size and have a volume fraction greater than about 0.15 within the metal matrix.
    Type: Grant
    Filed: November 17, 1995
    Date of Patent: September 9, 1997
    Assignee: Exxon Research & Engineering Company
    Inventors: Richard S. Polizzotti, Larry E. McCandlish, Edwin L. Kugler