Different Temperatures Patents (Class 419/54)
  • Patent number: 5009842
    Abstract: High strength steel parts or articles are made from a powder alloy by compacting the powder into a preform, sintering the preform in a sintering furnace or the like under a highly-reducing atmosphere and at a temperature of at least 1150.degree. C., cooling the preform, preheating the sintered preform in a highly-reducing atmosphere, such as an inert gas-based atmosphere containing hydrogen or pure hydrogen, to a temperature of at least 1000.degree. C. and transferring the preheated preform to an impact forging device and impacting the preform at a peak averaging forging pressure of at least about 1000 MPa to obtain a forged part or article. The time period between removal of the preheated preform from the preheater and the first forging impact is no more than about 8 seconds. The sintering and preheating steps can be combined with the sintered preform being cooled to the preheating temperature in the sintering furnace and transferred directly from the sintering furnace to the impact forging device.
    Type: Grant
    Filed: June 8, 1990
    Date of Patent: April 23, 1991
    Assignee: Board of Control of Michigan Technological University
    Inventors: Alfred A. Hendrickson, Darrell W. Smith
  • Patent number: 5009704
    Abstract: A nickel-based superalloy article formed from particles of the superalloy is processed to have a microstructure which is resistant to failure when processed using high strain thermomechanical processes. Articles having the desired microstrucuture are produced by hot isostatically pressing powder of the superalloy in a specified temperature range bounded by the incipient melting temperature as a minimum and the solvus temperature of stable high temperature phases. The compact is held under pressure in the specified temperature range to diffuse deleterious phases which exist as a result of the initial powder atomization operation. The powder compact thus formed can be processed using conventional processes to produce material for subsequent thermomechanical processing using high strain rate forging equipment and retain the benefits of chemical uniformity and cleanliness associated with traditional powder metal processes.
    Type: Grant
    Filed: June 28, 1989
    Date of Patent: April 23, 1991
    Assignee: Allied-Signal Inc.
    Inventor: Anthony Banik
  • Patent number: 5009706
    Abstract: Rare-earth alloy anisotropic powders consist of, in atomic percent, over 12 percent and not more than 20 percent of R (R is at least one on neodymium and praseodymium or at least one of them and or more rare-earth elements), not less than 4 percent and not more than 10 percent of boron, not less than 0.05 percent and not more than 5 percent of copper and the rest that consists of iron and unavoidable impurities. Up to 20 percent of the iron contained is replaceable with cobalt. The alloy powders are made up of flat crystal grains having mean thickness h (the shortest measure), d not smaller than 0.01 .mu.m and not larger than 0.5 .mu.m and ratio d/h not smaller than 2, where d is the means measure of the grains taken at right angles to the widthwide direction thereof, and the alloy powders are magnetically anisotropic.
    Type: Grant
    Filed: July 18, 1990
    Date of Patent: April 23, 1991
    Assignee: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Masahiro Fujikura, Toshio Mukai
  • Patent number: 5008071
    Abstract: A consolidated tungsten alloy body consisting essentially of from about 70% to about 98% by weight of tungsten, balance nickel and iron in essentially an 8:2 weight ratio. A process for producing the consolidated bodies where the tungsten content is greater than about 88% by weight comprises forming a relative uniform blend of the described metal powders, compacting the powders to form a green body then liquid phase sintering the green body to full density. For alloys containing less than about 90% tungsten solid state sintering can be used.
    Type: Grant
    Filed: November 25, 1988
    Date of Patent: April 16, 1991
    Assignee: GTE Products Corporation
    Inventors: James R. Spencer, James A. Mullendore
  • Patent number: 5002728
    Abstract: A method of manufacturing a soft magnetic Fe-Si alloy sintered product comprising a step of injection molding a composition comprising an Fe-Si powder mixture blended so as to contain from 1 to 10% by weight of Si and the substantial balance of Fe and a binder a step of applying binder-removal under heating to the resultant green body and applying a degassing and Si-diffusing; and a step of subsequently applying sintering. The sintered product is, preferably, applied with further heating for obtaining better soft magnetic property. Soft magnetic property of the sintered products is as comparable with or superior to products by conventional powder metallurgy.
    Type: Grant
    Filed: December 18, 1989
    Date of Patent: March 26, 1991
    Assignee: Sumitomo Metal Mining Company, Ltd.
    Inventors: Masakazu Achikita, Shinichi Sogame
  • Patent number: 5000909
    Abstract: A composite comprised of a sintered matrix of spinel ferrite and a non-exposed continuous phase of elemental silver or Ag-Pd alloy ranging to 25 atomic % Pd is produced by co-firing a laminated structure of ferrite powder-containing tapes containing non-exposed metallization-forming material. The composite can be formed into a composite product which contains a continuous silver or Ag-Pd alloy phase with two end portions wherein only the end portions are exposed.
    Type: Grant
    Filed: May 7, 1990
    Date of Patent: March 19, 1991
    Assignee: General Electric Company
    Inventors: Richard J. Charles, Achuta R. Gaddipati
  • Patent number: 4996022
    Abstract: A sintered body is produced by a process comprising the steps of mixing one or more metal powder particles with an organic binder, injection-molding the mixture to form a green body of a predetermined shape, removing the binder from the green body to form a porous body substantially made of the metal powder, and heating the porous body to a sintering temperature and holding it at that temperature to produce a sintered body, in which process the binder is removed through the sequence of the following steps: preheating the green body in an inert gas atmosphere in a temperature range that creates open pores in it; placing the green body, in which open pores have started to form, in a hydrogen gas atmosphere optionally mixed with an inert gas; holding the green body in a temperature range where the metal powder is not carburized and where the open pores will be maintained, so that the greater part of the binder is removed to form a porous body that is substantially made of the metal powder alone; and further hold
    Type: Grant
    Filed: July 10, 1990
    Date of Patent: February 26, 1991
    Assignees: Juki Corporation, Nippon Piston Ring Co., Ltd.
    Inventors: Norikazu Shindo, Tomoyuki Sekine, Yoshikatsu Nakamura, Takashi Kawamoto
  • Patent number: 4992238
    Abstract: Process for shaping and improving the mechanical properties of blanks produced by powder metallurgy from an alloy with increased high-temperature strength by extrusion, and the deformation is successively performed in at least two temperature ranges different from one another or in two phases, in that the blank (2) is first reduced in its cross section at a temperature T.sub.1 and then is either agin reduced in at a lower temperature T.sub.2 or is deformed at a temperature T.sub.3 under counterpressure so that its cross section is further widened. T.sub.3 can be smaller than or equal to T.sub.1.
    Type: Grant
    Filed: July 28, 1989
    Date of Patent: February 12, 1991
    Assignee: Asea Brown Boveri Ltd.
    Inventors: Malcolm Couper, Reinhard Fried
  • Patent number: 4992234
    Abstract: An improved method is proposed for the preparation of a sintered permanent magnet of a rare earth-iron-boron alloy having remarkably improved magnetic properties and stability by the powder metallurgical process. The scope of the inventive method consists in the particle size classification of the alloy powder for compression molding into a powder compact to be sintered, by which particles having a finer particle diameter and, preferably, a coarser particle diameter than the respective critical values are removed so as to effectively prevent oxidation of the too fine particles and improving the magnetic orientation of the particles as well as the sintering behavior of the particles.
    Type: Grant
    Filed: July 19, 1990
    Date of Patent: February 12, 1991
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Ken Ohashi, Masanobu Shimao
  • Patent number: 4990410
    Abstract: A surface refined sintered alloy with a burnt surface, comprising 75 to 95% by weight of a hard phase containing Ti, C and N as the essential components and otherwise comprising at least one of Zr, Hf, V, Nb, Ta, Cr, Mo and W and the balance of the alloy comprising a binder phase composed mainly of Co and/or Ni and inevitable impurities, wherein the sintered alloy satisfies at least two conditions selected from the group consisting of the following (1) to (3):(1) the average grain size of the hard phase in a surface layer to the inner portion of 0.05 mm from the burnt surface of the sintered alloy is 0.8 to 1.2-fold of the average grain size of the hard phase in the inner portion of the sintered alloy excluding the surface layer;(2) the average content of the binder phase in the surface layer to the inner portion of 0.05 mm from the burnt surface of the sintered alloy is 0.7 to 1.
    Type: Grant
    Filed: March 7, 1989
    Date of Patent: February 5, 1991
    Assignee: Toshiba Tungaloy Co., Ltd.
    Inventors: Takeshi Saitoh, Tuyoshi Saito, Mitsuo Ueki, Hisashi Suzuki, Keiichi Kobori
  • Patent number: 4988480
    Abstract: The proposed invention is used for the manufacture from the obtained composite of cutting tools, hard alloy tooling, dies and other products. A method according to the invention involves preparing a mixture, compacting it, placing the mixture into a synthesis zone, igniting the mixture, with subsequent reaction of components of the mixture under combustion conditions. Then cure is carried out during a period ranging from about 0.1 seconds to about 0.5 hours, and the hot combustion products are compacted under pressure at an average pressure rise rate ranging from about 10 to about 2000 kgf/cm.sup.2.s, with subsequent cure of the compacted product under isobaric conditions to complete homogenization of the composite, with subsequent cooling thereof to obtain an end composite.
    Type: Grant
    Filed: August 23, 1990
    Date of Patent: January 29, 1991
    Inventors: Alexandr G. Merzhanov, Inna P. Borovinskaya, Alexandr N. Pitjulin, Viktor I. Ratnikov, Konstantin L. Epishin, Vadim L. Kvanin
  • Patent number: 4989153
    Abstract: A sintering machine for applying heat and pressure to a die retained between two plate sets, includes a temperature sensor, a position sensor and a pressure sensor which are all connected to a computer for sensing the temperature of and pressure applied to the die, as well as the position of a movable one of the plate sets. This information is used to control a power supply unit which supplies current through the die to heat the die, and a hydraulic press for moving the movable one of the plate sets. Pressure and temperature are controlled in a discontinuous fashion during discrete intervals until a selected final temperature and pressure are reached. This more closely controls the sintering process over earlier systems which applied continously increasing temperature and pressure to the die.
    Type: Grant
    Filed: August 19, 1988
    Date of Patent: January 29, 1991
    Assignee: Sintris S.r.L.
    Inventor: Giuseppe Bonvini
  • Patent number: 4988386
    Abstract: A copper-tungsten mixture net-shaped product produced using powder metallurgical techniques with injection molding and liquid phase sintering. The product has a very low leak rate in helium gas, a high thermal conductivity and a rate of thermal expansion which is substantially the same as some glass and ceramic materials.
    Type: Grant
    Filed: June 29, 1988
    Date of Patent: January 29, 1991
    Assignee: Fine Particles Technology Corporation
    Inventors: James B. Oenning, Ian S. R. Clark
  • Patent number: 4985071
    Abstract: A process for producing a thin film of a base metal on a substrate which comprises thermally decomposing in oxidative atmosphere an organic or inorganic compound containing a base metal compound formed on a substrate to form the oxide of the metal and then reducing the oxide by heat-treating it in reductive atmosphere. A temperature sensor, magnetic sensor, and ceramic wiring substrate utilizing the base metal thin film.
    Type: Grant
    Filed: January 12, 1989
    Date of Patent: January 15, 1991
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Munehiro Tabata, Chiharu Hayashi, Yasuhito Isozaki, Kazuyuki Okano, Yo Hasegawa
  • Patent number: 4983354
    Abstract: A tungsten carbide powder and cemented tungsten carbide article made from the powder are disclosed. The powder has a particle size of greater than 20 micrometers in diameter and no particles less than one-half the average particle size or greater than two and one-half times the average particle size.
    Type: Grant
    Filed: February 10, 1989
    Date of Patent: January 8, 1991
    Assignee: GTE Products Corporation
    Inventors: David A. Reeder, Carlos Lopez, Jack L Burwick
  • Patent number: 4979984
    Abstract: A process is claimed for the manufacture of an insert. The process includes the steps of filling a die cavity defined by a die mold with powdered metal, the die cavity conforming to the required shape of the insert. The powdered metal is compressed within the die cavity such that a compact of the insert is formed within the die cavity. The compact is sintered within a sintering furnace so that a first porton of the compact is in the solid phase and a second portion of the compact is in the liquid phase. The compact is rapidly cooled within the sintering furnace to a temperature below the melting point of the powdered metal. Such temperature is maintained so that densification of the first portion to substantially full density is achieved. The arrangement is such that the profile integrity of the compact is retained. the resltant insert is then subsequently cooled.
    Type: Grant
    Filed: March 16, 1990
    Date of Patent: December 25, 1990
    Assignee: Inserts Ltd.
    Inventor: Linwood R. Anderson
  • Patent number: 4980126
    Abstract: A single step is relied on in the canning process for hot isostatic pressing metallurgy composites. The composites are made from arc-sprayed and plasma sprayed monotape. The HIP can is of compatible refractory metal and is sealed at high vacuum and temperature. This eliminates out-gassing during hot isostatic pressing.
    Type: Grant
    Filed: November 9, 1989
    Date of Patent: December 25, 1990
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: John J. Juhas
  • Patent number: 4980122
    Abstract: A superplastic composite material is produced by thoroughly and homogeneously mixing particles or whiskers of silicon nitride and aluminum metal powder in a solvent, then removing the solvent from the resultant mixture, sintering the residual mixture at an elevated temperature, further compressing it at an elevated temperature, then hot extrusion-molding the compressed mixture thereby forming a shaped article, and heat-treating this shaped article.
    Type: Grant
    Filed: March 23, 1990
    Date of Patent: December 25, 1990
    Assignee: Agency of Industrial Science & Technology, Ministry of International Trade & Industry
    Inventors: Tsunemichi Imai, Mamoru Mabuchi
  • Patent number: 4975035
    Abstract: The cathode-forming method involves incorporating cobalt into a nickel plaque so that the exposed surfaces and the pores of the nickel plaque are uniformly covered with cobalt. The plaque is then treated to form nickel hydroxide in the pores and on the surfaces thereof. The cobalt is thus diposed at the interfacial boundary of the nickel plaque and nickel hydroxide so as to reduce the impedance and enhance charge conduction of the cathode. The mode of incorporation can vary. Thus, the sintered nickel plaque can be soaked in an aqueous solution of a water-soluble salt of cobalt, such as cobalt nitrate, then dried and resintered. Another mode involves dispersing a water-soluble cobalt salt in an aqueous slurry of nickel particles and water-soluble binder for the particles. The nickel particles are thus uniformly covered with the dissolved cobalt salt and then are compacted into a plaque. The plaque is dried and finally sintered.
    Type: Grant
    Filed: January 13, 1989
    Date of Patent: December 4, 1990
    Inventors: Jerry Kuklinski, Phillip G. Russell
  • Patent number: 4973355
    Abstract: The invention relates to sintered hard metals having high cutting properties, particularly plastic deformation resistance at high temperatures, crater resistance and the like, suitable for use as cutting tools, wear resistant tools and materials for dies, and the method for producing the same. The invention has for an object to obtain both sintered hard metals having the aforesaid high properties by sintering metallic components comprising IVa group metals, VIa group metals or metals of both groups substituted by Va group metals up to 60 mol % respectively, a B-1 type solid solution hard phase consisting of non-metallic components of C, N and O, and a metallic bonding phase, in a CO gas atmosphere, and to sintered hard metals in which an uniform hardness is imparted to the surface and interior thereof by the method of sintering the said sintered hard metal in a CO gas atmosphere.
    Type: Grant
    Filed: October 31, 1988
    Date of Patent: November 27, 1990
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kunihiro Takahashi, Toshio Nomura, Takaharu Yamamoto
  • Patent number: 4970050
    Abstract: A method of producing a sintered, very high density dental prosthesis from a suspension containing noble-metal powder mixtures with bi or multimodal particle-size distribution and a mixing liquid. The suspension is molded to the desired shape and then the dental prosthesis is dried. The molded dental prosthesis is then heat-treated 5 to 45 minutes between 100.degree. and 400.degree. C., then heated with an average temperature elevation of 50 to 300 K/min. to 800.degree. C. and then brought to the sintering temperature T at 20 to 200 K/min. The sintering temperature T is between T.sub.solidus - 200) and T.sub.solidus - 70), whereby T.sub.solidus is the solidus temperature of the sintered alloy. The cooling-down of the dental prosthesis takes place under a vacuum or a protective gas.
    Type: Grant
    Filed: December 13, 1989
    Date of Patent: November 13, 1990
    Inventors: Werner Groll, Angela Klaus, Thomas Lange
  • Patent number: 4968347
    Abstract: A high energy rare earth-ferromagnetic metal permanent magnet is disclosed which is characterized by improved intrinsic coercivity and is made by forming a particulate mixture of a permanent magnet alloy comprising one or more rare earth elements and one or more ferromagnetic metals and forming a second particulate mixture of a sintering alloy consisting essentially of 92-98 wt. % of one or more rare earth elements selected from the class consisting of Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and mixtures of two or more of such rare earth elements, and 2-8 wt. % of one or more alloying metals selected from the class consisting of Al, Nb, Zr, V, Ta, Mo, and mixtures of two or more of such metals. The permanent magnet alloy particles and sintering aid alloy are mixed together and magnetically oriented by immersing the mixture in an axially aligned magnetic field while cold pressing the mixture.
    Type: Grant
    Filed: November 22, 1988
    Date of Patent: November 6, 1990
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Ramamoorthy Ramesh, Gareth Thomas
  • Patent number: 4964907
    Abstract: A process is provided for the production of a sintered body. The process includes the following consecutive steps: (i) mixing and kneading one or more metal powders and/or one or more alloy powder with a binder into a compound, said metal and alloy powders having an average particle size not greater than 30 .mu.m, (ii) injection-molding the compound into a green body; (iii) debinding the green body to form a debound body; and (iv) subjecting the debound body to first-stage sintering at 1,050.degree.-1,250.degree. C. in a reducing or reduced-pressure atmosphere and then to second-stage sintering at a temperature in a range of 1,100.degree.-1,400.degree. C. which is higher than that of the first-stage sintering. This process can provide sintered Ti bodies and sintered magnetic bodies of the Fe-Si type, which have a density ratio of at least 95%.
    Type: Grant
    Filed: August 14, 1989
    Date of Patent: October 23, 1990
    Assignee: Kawasaki Steel Corp.
    Inventors: Yoshisato Kiyota, Junichi Ohta, Hiroshi Ohtsubo, Shigeaki Takajo
  • Patent number: 4963321
    Abstract: There are disclosed a surface sintered alloy with a burnt surface, comprising 75 to 95% by weight of a hard phase containing Ti, C and N as the essential components and otherwise comprising at least one of Zr, Hf, V, Nb, Ta, Cr, Mo and W and the balance of the alloy comprising a binder phase composed mainly of Co and/or Ni and inevitable impurities, wherein the sintered alloy satisfies at least one condition selected from the group consisting of the following (1) to (3):(1) the average grain size of the hard phase in a surface layer to the inner portion of 0.05 mm from the burnt surface of the sintered alloy is 0.8 to 1.2-fold of the average grain size of the hard phase in the inner portion of the sintered alloy excluding the surface layer;(2) the average content of the binder phase in the surface layer to the inner portion of 0.05 mm from the burnt surface of the sintered alloy is 0.7 to 1.
    Type: Grant
    Filed: October 19, 1989
    Date of Patent: October 16, 1990
    Assignee: Toshiba Tungaloy Co., Ltd.
    Inventors: Takeshi Saitoh, Tuyoshi Saito, Mitsuo Ueki, Hisashi Suzuki, Keiichi Kobori
  • Patent number: 4963320
    Abstract: A method for producing an anisotropic rare earth magnet is improved by applying compressing stress on a free surface of an compacted material at the time of extruding the compacted material in order to prevent forming cracks, and improved by using a double action punch provided with a core punch and a sleeve punch so as to mold a compacted material and extrude the compacted material into the anisotropic magnet material in a single heat process continuously.
    Type: Grant
    Filed: April 11, 1990
    Date of Patent: October 16, 1990
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Makoto Saito, Teruo Watanabe, Shinichiro Yahagi, Yasuaki Kasai, Norio Yoshikawa, Yutaka Yoshida, Toshiya Kinami, Hiyoshi Yamada
  • Patent number: 4961902
    Abstract: A method for manufacturing ceramic/metal or ceramic/ceramic composite articles is disclosed. The articles can be useful for the production of aluminum in fused salt electrolysis cells, as armour plates for the protection against projectiles, cutting tools, or in abrasion resistance applications. The temperature slope of the process if optimized such that one of the reactants in the manufacturing proceeds through peritectic decomposition at a heating rate of low temperature increase for desirably uniform temperature distribution over the reaction mixture. Then the temperature increase is greatly elevated to obtain a reaction sintering condition for avoiding grain growth of undesired reaction products. Elevated temperature reaction sintering conditions can be maintained to decompose undesired components before they are entrapped by the reaction product.
    Type: Grant
    Filed: January 6, 1987
    Date of Patent: October 9, 1990
    Assignee: Eltech Systems Corporation
    Inventors: Thomas M. Clere, Gholamreza J. Abbaschian, Douglas J. Wheeler, Albert L. Barnes
  • Patent number: 4954166
    Abstract: The pyrophoric fines inevitably resulting from the crushing of zirconium and/or hafnium or other exotic metal fines, such as titanium and uranium, are brought into contact with molten magnesium or a molten mixture of magnesium and magnesium chloride in the usual vacuum distillation furnace so that their surfaces are wetted by the molten material, after which furnace temperature is dropped to solidify the molten material about the fines. Furnace temperature is then raised to that required to vaporize the magnesium and magnesium chloride, whereupon sintering of the fines takes place over a period of time.
    Type: Grant
    Filed: November 17, 1989
    Date of Patent: September 4, 1990
    Assignee: Westinghouse Electric Corp.
    Inventors: Hani A. M. Abodishish, Randy W. Wahlquist, Dale A. Lopez
  • Patent number: 4948426
    Abstract: A sintering metal powder consisting of metal particles having a particle diameter distribution including a plurality of peaks. The larger of the two particle diameters at every adjoining two, respectively, of the peaks has a ratio of between 5 and 10 to the smaller. The height of one of every adjoining two of the peaks has a ratio of between 1 and 5 to that of the other that is not higher than the one peak. The particle diameter at one of every adjoining two of the peaks which is not higher than the other is smaller than that at the other peak. The particle diameter at the highest peak is between 30 and 80 microns. A process for making a sintered product from such a powder is also disclosed.
    Type: Grant
    Filed: January 22, 1990
    Date of Patent: August 14, 1990
    Assignee: Sumitomo Metal Mining Company Limited
    Inventors: Yutaka Kato, Yoshio Kijima
  • Patent number: 4938799
    Abstract: The invention relates to heavy tungsten-nickel-iron alloys with high mechanical characteristics and a specific gravity between 15.6 and 18. The alloys include a tungsten .alpha.-phase in the shape of butterfly wings with dislocation cells of dimensions between 0.1 and 1 .mu.m, and a nickel-iron bonding .gamma.-phase having a mean free path of less than 15 .mu.m and an Ni/Fe ratio greater than or equal to 2.
    Type: Grant
    Filed: October 5, 1988
    Date of Patent: July 3, 1990
    Assignee: Cime Bocuze
    Inventor: Guy Nicolas
  • Patent number: 4937042
    Abstract: A mixture of two powdered alloys of the M, Cr, Al type, M being Co and/or Ni, is disclosed, in one form, for use in providing an abradable surface of an article and is characterized by the substantial absence of B. The first alloy has substantially no Si and has a higher melting range than that of the second alloy. The second alloy has substantially no Y and consists essentially of, by weight, 8-12% Si, 1.5-4% Al, 10-30%Cr, with the balance M and incidental impurities. The total mixture composition consists essentially of, by weight, 10-35% Cr, 4-10% Al, from a small but effective amount up to about 0.09% Y, 2-6% Si, with the balance M and incidental impurities.
    Type: Grant
    Filed: March 23, 1989
    Date of Patent: June 26, 1990
    Assignee: General Electric Company
    Inventors: Roger J. Perkins, Murray S. Smith, Jr.
  • Patent number: 4923512
    Abstract: Cobalt-bound tungsten carbide metal matrix composites having a unique microstructure are produced by consolidating partially sintered greenware under high pressures, e.g., 120,000 psi, at temperatures less than those used for conventional liquid phase sintering in a relatively short time, e.g., from less than one minute to less than about one hour. The composites have a binder phase which contains less than about 80 weight percent of the tungsten found in a composite prepared from the same or similar compositions via liquid phase sintering. These composites provide cutting tools with both toughness and wear resistance which exceed that of cutting tools made from the same or similar compositions via liquid phase sintering.
    Type: Grant
    Filed: April 7, 1989
    Date of Patent: May 8, 1990
    Assignee: The Dow Chemical Company
    Inventors: Ed E. Timm, Douglas B. Schwarz
  • Patent number: 4923513
    Abstract: A carefully controlled amount of hydrogen is diffused into titanium or its alloys at an elevated temperature above the transformation temperature. After the elevated temperature is maintained for an approprate duration of time, eutectoid transformation is performed in an inert atmosphere, again for an appropriate period of time, during which or alternatively after which the hydrogen is removed and the metal cooled to room temperature. A sintered titanium alloy component of the type intended for use as a joint replacement subjected to such a treatment displays a fatigue strength which is noticeably improved over a similar article with an equiaxed or lamellar microstructure.
    Type: Grant
    Filed: April 21, 1989
    Date of Patent: May 8, 1990
    Assignee: Boehringer Mannheim Corporation
    Inventors: Paul Ducheyne, David H. Kohn
  • Patent number: 4921666
    Abstract: A process for high efficiency hot isostatic pressing in a hot isostatic pressing treatment for sintering or densifying a ceramic or metallic work in a high temperature and high pressure gas atmosphere, comprising preheating the work outside a high pressure vessel prior to the hot isostatic pressing treatment, transferring the preheated work as surrounded with the gas in a hot state into the high pressure vessel, then treating the work at high temperature and high pressure in a gas atmosphere, thereafter taking out the work from the high pressure vessel together with the gas atmosphere, then cooling the work if necessary, and subsequently taking it out from the gas atmosphere, as well as an apparatus for practicing the above process, wherein a treating chamber for effecting the hot isostatic pressing treatment is covered with a hermetic casing, and at least one valve mechanism capable of providing communication and cut-off between the interior and exterior of the treating chamber is provided in each of upper a
    Type: Grant
    Filed: November 29, 1984
    Date of Patent: May 1, 1990
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventor: Takahiko Ishii
  • Patent number: 4917859
    Abstract: The present invention provides a dewaxing process for metal powder compact which comprises the steps of embeding in alumina powder an injection-molded metal powder compact consisting of metal powder and an organic binder including low melting point substances; heating the embeded compact to a temperature of 200.degree. C. in a chemically inert atmosphere in a dewaxing furnace, thereby removing the low melting point substances from the compact without deformation of the compact; placing the compact in a closed sintering vessel so as to keep the surrounding temperature constant and disposing the vessel in a vacuum furnace; evacuating the vacuum furnace; and removing the organic binder by heating to a temperature of 550.degree. to 650.degree. C. at a heating rate of 300.degree. to 600.degree. C./hr while supplying an inert gas into the vacuum furnace.
    Type: Grant
    Filed: September 6, 1989
    Date of Patent: April 17, 1990
    Assignee: Mitsubishi Steel Mfg. Co., Ltd.
    Inventor: Kazunori Hamo
  • Patent number: 4915899
    Abstract: The invention comprises a process for co-sintering of conductors of copper or copper-based alloy and a ceramic substrate, the substrate being produced from a ceramic powder of cordierite type, having a sintering temperature of lower than 950.degree. C.The process comprises the following steps:(a) shaping of the ceramic substrate from a powder of cordierite type,(b) deposit of copper on the ceramic substrate, and(c) co-sintering heat treatment, during which the organic compounds are removed, the copper is regenerated in a reducing atmosphere, and co-sintering of the conductors and the substrate is carried out in a flow of moist inert gas with a plateau at a temperature of between 1065.degree. and 1080.degree. C.The process according to the invention makes it possible to produce substrates of cordierite with internal and external conductors.
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: April 10, 1990
    Assignee: Pechiney Recherche Groupement d'Interet Economique
    Inventors: Veronique Oliver, Jean-Louis Guille, Jean-Claude Bernier, Claude Drapier
  • Patent number: 4913739
    Abstract: A process for the powder metallurgical production of structural parts of high strength and hardness from silicon-manganese or silicon-manganese-carbon alloyed steels. The alloying elements Si and Mn or Si, Mn and C are mixed, in powder form, by way of the alloy carriers ferrosilicon, ferromanganese or a silicon-manganese-iron master alloy containing silicon and manganese in the ranges from 10 to 30 weight percent Si, 20 to 70 weight percent Mn, remainder Fe, with an iron powder and when carbon is present with graphite, to form a powder mixture. The powder mixture is compressed and sintered at a temperature in a range from 1150.degree. C. to 1250.degree. C. and then cooled.
    Type: Grant
    Filed: March 8, 1985
    Date of Patent: April 3, 1990
    Assignee: Kernforschungszentrum Karlsruhe GmbH
    Inventors: Fritz Thummler, Aloisio N. Klein, Rainer Oberacker
  • Patent number: 4911626
    Abstract: A long life high current density cathode is made from a mixture of tungsten nd iridium powders by processing the mixture of powders with an activator into a porus billet, and then impregnating the billet with a mixture of barium peroxide and a coated emitter by firing the billet in a dry hydrogen furnace at a temperature at which the impregnant melts.
    Type: Grant
    Filed: November 20, 1989
    Date of Patent: March 27, 1990
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Louis E. Branovich, Bernard Smith, Gerard L. Freeman, Donald W. Eckart
  • Patent number: 4906529
    Abstract: A method is provided for producing an erosion-resistant layer or coating on the surface of a metallic workpiece. The method includes providing a thermally sprayable alloy of Ni-Cr-Fe-B-Si and thermally spraying the alloy on the workpiece to a specified thickness, following which the sprayed-on layer is heated in vacuum to a temperature between 250.degree. C. to 400.degree. C. for a time at the stated temperature of about 5 to 30 minutes sufficient to effect degassing of the layer. The temperature of the layer is thereafter raised to a range of about 800.degree. C. to 950.degree. C. and maintained at that temperature in vacuum for between 5 to 30 minutes. The temperature at the layer is then raised to between 900.degree. C. and 1100.degree. C. under a protctive atmoshpere at a pressure of between 200 to 600 mm Hg to effect fursion of the layer at above its melting point, following which the coated metallic workpiece is finally cooled to room temperature under the protective atmosphere.
    Type: Grant
    Filed: February 4, 1987
    Date of Patent: March 6, 1990
    Assignee: Castolin S.A.
    Inventors: Niels Brundbjerg, Wolfgang Simm
  • Patent number: 4904538
    Abstract: A single step is relied on in the canning process for hot isostatic pressing powder metallurgy composites. The binders are totally removed while the HIP can of compatible refractory metal is sealed at high vacuum and temperature. This eliminates out-gassing during hot isostatic pressing.
    Type: Grant
    Filed: March 21, 1989
    Date of Patent: February 27, 1990
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: John J. Juhas
  • Patent number: 4904537
    Abstract: An improved process and an improved composite bearing material produced thereby comprising a hard metal backing strip having leaded-bronze bearing lining tenaciously bonded to at least one face surface thereof and wherein the bearing lining is characterized by having the lead constituent thereof substantially uniformly distributed throughout the lining matrix in the form of extremely fine-sized particles providing improved operating characteristics to the bearing materials fabricated therefrom.
    Type: Grant
    Filed: October 14, 1987
    Date of Patent: February 27, 1990
    Assignee: Federal-Mogul Corporation
    Inventor: Michael D. Lytwynec
  • Patent number: 4895699
    Abstract: A cathode is made from a mixture of tungsten and iridium powders using a ction product formed from reacting barium peroxide with an excess of tungsten as the impregnant.
    Type: Grant
    Filed: August 24, 1989
    Date of Patent: January 23, 1990
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Louis E. Branovich, Gerard L. Freeman, Bernard Smith, Donald W. Eckart
  • Patent number: 4892703
    Abstract: A surface structure of A1N substrate comprising:an A1N substrate,an intermediate layer disposed on the A1N substrate, anda metallized layer disposed on said intermediate layer, said intermediate layer comprising at least aluminum, nitrogen and oxygen. The metallized layer has a main component of one of Mo-Mn alloy, Mo and W, and has a thickness of 1-20 .mu.m,This surface structure is produced by coating a surface of A1N substrate with metallizing layer components, heat treating the resultant coated substrate at a temperature of 200.degree.-500.degree. C. under an oxidizing atmosphere, and further heating the heat treated coated substrate at a temperature of 1200.degree.-1400.degree. C. under a nonoxidizing atmosphere having a dew point of -35.degree.to 5.degree. C.
    Type: Grant
    Filed: March 24, 1989
    Date of Patent: January 9, 1990
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Satoshi Iio, Akiyasu Okuno
  • Patent number: 4889685
    Abstract: A titanium composite having a coil-shaped skeletal structure on the surface, comprising a titanium or titanium alloy substrate and one or more layers of a coil-shaped skeletal titanium or titanium alloy structure that is firmly attached to the surface of said substrate and a process for producing a titanium composite having a coil-shaped skeletal structure on a surface of a titanium or titanium alloy substrate, which comprises: providing a coating composition which is a mixture of a titanium or titanium alloy powder with a binder; applying said composition in such a manner that titanium or titanium alloy coils which are to form the coil-shaped skeletal structure are firmly attached to both themselves and to the titanium or titanium alloy substrate; the heating the assembly either in vacuo or in an inert atmosphere so that the titanium or titanium alloy powder in the applied coating composition is sintered to have the coil-shaped skeletal titanium or titanium alloy structure attached firmly onto the titanium o
    Type: Grant
    Filed: November 28, 1986
    Date of Patent: December 26, 1989
    Assignee: Permelec Electrode Ltd.
    Inventors: Takayuki Shimamune, Masashi Hosonuma
  • Patent number: 4888068
    Abstract: A process for manufacturing a rare earth-iron-boron alloy permanent magnet by, after sintering, keeping the sintered alloy at temperatures of 750.degree.-1000.degree. C. for 0.2-5 hours, slowly cooling it at a cooling rate of 0.3.degree.-5.degree. C./min. to temperatures between room temperature and 600.degree. C.; annealing it at temperatures of 550.degree.-700.degree. C. for 0.2-3 hours, and rapidly cooling it at a cooling rate of 20.degree.-400.degree. C./min. The permanent magnet contains a matrix, a B-rich phase and a Nd-rich phase. In grain boundaries of the matrix phases covered by bcc phases, thin, fine plates of the bcc phases projecting into the matrix phases are once increased by the first heat treatment and slow cooling and then eliminated by the annealing.
    Type: Grant
    Filed: October 4, 1985
    Date of Patent: December 19, 1989
    Assignee: Hitachi Metals, Ltd.
    Inventors: Masaaki Tokunaga, Minoru Endoh, Noriaki Meguro, Shigeho Tanigawa
  • Patent number: 4886639
    Abstract: Structural component made of powder metallurgical materials, particularly temperature resistant alloys, nickel base alloys, are produced by injection molding or pressing. The sintering is divided into individual work steps for producing dense and smooth structural components which are true to shape.
    Type: Grant
    Filed: April 30, 1987
    Date of Patent: December 12, 1989
    Assignee: MTU Motoren- und Turbinen-Union Muenchen GmbH
    Inventors: Gerhard Andrees, Josef Kranzeder, Wilhelm Vogel
  • Patent number: 4885133
    Abstract: A wear-resistant sintered iron-based alloy and a process for producing the alloy are described, wherein the alloy comprises a first phase having a martensite composition which comprises from 0.5 to 3.0 wt % of Cr, from 0.4 to 1.0 wt % of Mn, from 0.1 to 0.4 wt % of Mo, and the balance of Fe, based on the total amount of said first phase; a second phase having a martensite and Cr carbide composition which comprises from 10 to 20 wt % of Cr and the balance of Fe, based on the total amount of said second phase; and from 1.0 to 2.5 wt % of C, based on the total amount of said alloy; wherein said first phase and said second phase are present as a mixture containing from 10 to 80% by volume of said second phase, based on the total volume of said alloy; and said alloy is substantially free from any residual austenite.
    Type: Grant
    Filed: April 6, 1989
    Date of Patent: December 5, 1989
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Satoshi Fujii
  • Patent number: 4880599
    Abstract: A composite comprised of a sintered matrix of spinel ferrite and an electrically conductive phase of elemental silver is produced by co-firing a laminated structure of ferrite powder-containing tapes containing a silver metallization-forming material having two end portions wherein only the end portions are exposed.
    Type: Grant
    Filed: March 25, 1988
    Date of Patent: November 14, 1989
    Assignee: General Electric Company
    Inventors: Richard J. Charles, Achuta R. Gaddipati
  • Patent number: 4871438
    Abstract: Cermet electrode compositions comprising NiO-NiFe.sub.2 O.sub.4 -Cu-Ni, and methods for making, are disclosed. Addition of nickel metal prior to formation and densification of a base mixture into the cermet allows for an increase in the total amount of copper and nickel that can be contained in the NiO-NiFe.sub.2 O.sub.4 oxide system. Nickel is present in a base mixture weight concentration of from 0.1% to 10%. Copper is present in the alloy phase in a weight concentration of from 10% to 30% of the densified composition. Such cermet electrodes can be formed to have electrical conductivities well in excess of 100 ohm.sup.-1 cm.sup.-1. Other alloy and oxide system cermets having high content metal phases are also expected to be manufacturable in accordance with the invention.
    Type: Grant
    Filed: November 3, 1987
    Date of Patent: October 3, 1989
    Assignee: Battelle Memorial Institute
    Inventors: Steven C. Marschman, Norman C. Davis
  • Patent number: 4871437
    Abstract: Cermet electrode compositions and methods for making are disclosed which comprise NiO--NiFe.sub.2 O.sub.4 --Cu--Ni. Addition of an effective amount of a metallic catalyst/reactant to a composition of a nickel/iron/oxide, NiO, copper, and nickel produces a stable electrode having significantly increased electrical conductivity. The metallic catalyst functions to disperse the copper and nickel as an alloy continuously throughout the oxide phase of the cermet to render the electrode compositon more highly electrically conductive than were the third metal not present in the base composition. The third metal is preferably added to the base composition as elemental metal and includes aluminum, magnesium, sodium and gallium. The elemental metal is converted to a metal oxide during the sintering process.
    Type: Grant
    Filed: November 3, 1987
    Date of Patent: October 3, 1989
    Assignee: Battelle Memorial Institute
    Inventors: Steven C. Marschman, Norman C. Davis
  • Patent number: 4867943
    Abstract: A starting material for injection molding of a metal powder including from 38 to 46% by volume of an organic binder and the balance of spherical iron powder with an average particle size from 2 to 6.5 .mu.m and having high density sinterability at low sintering temperature, and a method of producing a sintered parts by conducting injection molding, debinding and sintering using the above-mentioned starting material in a non-oxidizing atmosphere at a temperature lower than the A.sub.3 transformation point.
    Type: Grant
    Filed: December 12, 1988
    Date of Patent: September 19, 1989
    Assignee: Kawasaki Steel Corporation
    Inventor: Yoshisato Kiyota