Controlled Cooling After Sintering Patents (Class 419/25)
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Patent number: 7108830Abstract: A method of production of large Ingots of neutron attenuating composites using a vacuum-bellows system allows for large cross-sectional shapes to be extruded and rolled. This method uses a vacuum-bellows technology which allows the manufacturing of large 8–16 inch diameter ingots (50–450 lbs. each). A variety of primary metal matrix materials can be used in this technology. High specific strength and stiffness can be achieved because the technology allows for final densities of 99% and higher. The vacuum-bellows technology allows metals and ceramics to blend and mesh together at compression pressures of 800 tons with elevated temperatures. The controlled compression movement allows for any oxide layer, on the metal, to be broken up and consolidated with the chosen ceramic particulate. One application is to blend boron-rich ceramics and high purity (99.5–99.99%) aluminum particulates together and produce a large ingot using this vacuum-bellows technology.Type: GrantFiled: September 9, 2002Date of Patent: September 19, 2006Assignee: Talon CompositesInventor: Robin A. Carden
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Patent number: 7037466Abstract: After recycled titanium alloy chips are crushed and cleaned, they are pressed into cylindrically briquettes with a relative density of 0.6, and placed into capsules. The capsules are heated and placed into a preheated pressing rig. The pressing rig repetitively applies axial force to the capsule, resulting in a relative density of at least 0.95. The product billets are used for consumable electrodes, secondary casting alloys, forgings, extruded semi-finished products and the like.Type: GrantFiled: September 29, 2003Date of Patent: May 2, 2006Inventors: Vladimir Leonidovich Girshov, Arnold Nikolayevich Treschevskiy, Victor Georgievich Kochkin, Alexey Alexandrovich Abramov, Natalja Semenovna Sidenko
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Patent number: 6821478Abstract: The invention relates to a method for sintering aluminium-based sintered parts which are, initially, guided with the aid of a transport system T through a de-binding area (3) before being guided through followed by a sintering area (2) and finally being guided through a cooling area (4). Inert gas atmosphere prevails in the sintering area (2), provided with an oxygen content, corresponding to a thawing point of, maximum, 40° C. The sintered parts (23) are heated to the required sintering temperature of 560-620° C., by means of convection, whereby the inert gas atmosphere is accordingly heated, flowing around said sintered parts in a corresponding manner.Type: GrantFiled: December 26, 2002Date of Patent: November 23, 2004Assignee: Eisenmann Maschinenbau KGInventor: Hartmut Weber
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Patent number: 6679932Abstract: A ferrous sintered valve seat material is made of mixed powders comprising a sinter-hardenable phase and a finely dispersed carbide phase. The powder mixture comprises a sinter-hardening prealloyed powder forming 75 to 90 wt. % of the mixture and a tool steel powder with finely dispersed carbides forming 5 to 25% of the mixture. Machinability additives of MnS, CaF2 or MoS2 types are added in an amount of 1 to 5 wt. %. Improved thermal conductivity is obtained by infiltrating the compact with Cu up to 25 wt. %.Type: GrantFiled: April 30, 2002Date of Patent: January 20, 2004Assignee: Federal-Mogul World Wide, Inc.Inventors: Mark Birler, Salvator Nigarura, Juan Trasorras
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Patent number: 6638474Abstract: A coated cemented carbide tool, and a method for making the same, wherein the as-sintered substrate is formed by sintering in an atmosphere having at least a partial pressure and for a part of the time a nitrogen partial pressure.Type: GrantFiled: March 19, 2001Date of Patent: October 28, 2003Assignee: Kennametal Inc.Inventors: Yixiong Liu, Donald A. Botbyl, George P. Grab, Mark S. Greenfield
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Patent number: 6630101Abstract: A method of producing a gear from a metallurgical powder includes molding at least a portion of the powder to provide a gear preform. The gear preform is sintered and hot formed, and subsequently may be carburized. The gear preform is resintered and cooled at a cooling rate suitable to provide a bainitic microstructure in at least a surface region of the preform. The gear teeth of the preform may be shaved to, for example, adjust dimensions, and enhance dimensional uniformity.Type: GrantFiled: August 16, 2001Date of Patent: October 7, 2003Assignee: Keystone Investment CorporationInventors: Gary L. Anderson, William J. Olson
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Publication number: 20030138341Abstract: A method to produce a sintered metal with an improved abrasion resistance and durability, and a rotary compressor flange produced by use of the method. The sintered metal is produced by kneading metal powder, pressure molding the kneaded powder, and sintering the molded powder. The sintered metal is further produced by subzero treating the sintered metal powder for a predetermined time and tempering the resulting sintered metal powder under a predetermined compression residual stress.Type: ApplicationFiled: June 4, 2002Publication date: July 24, 2003Applicant: Samsung Electronics Co., Ltd.Inventors: Dong-Jun Choi, Sie-Hyeong Kim, Sung-Gyun Lim
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Publication number: 20030035747Abstract: A method of producing a gear from a metallurgical powder includes molding at least a portion of the powder to provide a gear preform. The gear preform is sintered and hot formed, and subsequently may be carburized. The gear preform is resintered and cooled at a cooling rate suitable to provide a bainitic microstructure in at least a surface region of the preform. The gear teeth of the preform may be shaved to, for example, adjust dimensions, and enhance dimensional uniformity.Type: ApplicationFiled: August 16, 2001Publication date: February 20, 2003Inventors: Gary L. Anderson, William J. Olson
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Patent number: 6506226Abstract: The invention relates to a hard metal or cermet body with a hard material phase consisting of WC and/or at least one carbide, nitride, carbonitride and/or oxicarbonitride of at least one of the elements from group IVa, Va, or VIa of the periodic table and a binding metal phase consisting of Fe, Co and/or Ni, said binding metal phase making up 3 to 25 mass %. In particular, WC crystallites should protrude beyond the hard metal or cermet surface of the by 2 to 20 &mgr;m in order to improve the adhesion of surface layers that are applied.Type: GrantFiled: November 3, 2000Date of Patent: January 14, 2003Assignee: Widia GmbHInventors: Limin Chen, Walter Lengauer, Hans Werner Daub, Klaus Dreyer, Dieter Kassel, José Garcia, Georg Korb
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Publication number: 20020150495Abstract: A method for metal processing is provided in which a cooling atmosphere comprising hydrogen is used for accelerated cooling of a processed metal part in a furnace, resulting in improved properties for the metal part. A sintering furnace is also provided and comprises a means for inhibiting gas flows between a heating zone and a cooling zone of the furnace.Type: ApplicationFiled: March 9, 2001Publication date: October 17, 2002Inventor: Raymond E. Serafini
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Patent number: 6350406Abstract: A method of manufacturing a sintered anode unit for a solid electrolytic capacitor is provided. According to this method, a press-molded or compacted pellet of a valve-action metal powder is sintered at a predetermined high temperature and in a predetermined primary vacuum. The pellet is naturally cooled in this primary vacuum, and is cooled by force cooling in an inert gas atmosphere. Thereafter, the sintered pellet is subjected to a repeated cycle processing of vacuum, atmospheric leakage, and vacuum in a gradual-oxidizing chamber. The atmospheric leakage level is increased step by step to set the vacuum level in the gradual-oxidizing chamber to the atmospheric pressure. Then, the sintered pellet having the restricted content of oxygen is taken out from the gradual-oxidizing chamber into the atmosphere.Type: GrantFiled: November 3, 2000Date of Patent: February 26, 2002Assignee: NEC CorporationInventors: Hideaki Satou, Yoshio Ida
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Patent number: 6264886Abstract: There is provided a sintered metallic alloy having toughness capable of supporting stress at a point by distributing structure portions having different values of rigidity approximately uniformly without separation of layers different in brashiness. A method of manufacturing the sintered metallic alloy and a sintered alloy gear employing the sintered metallic alloy are also provided. Metallic materials are formed into a predetermined configuration. Then, the metallic materials is sintered in a sintering furnace (14) to make a sintered metallic alloy. Next, the sintered metallic alloy is cooled gradually to an ambient atmosphere of room temperature. Finally, the temperature of the cooled metallic alloy is raised and a toughness stabilizing process is performed in a low-temperature furnace (18) so that structures with high toughness are distributed approximately uniformly.Type: GrantFiled: October 21, 1998Date of Patent: July 24, 2001Assignee: JATCO CorporationInventors: Muneo Mizuta, Yasushi Yabe, Yoshihisa Tomihari
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Patent number: 6258147Abstract: 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: GrantFiled: January 19, 2000Date of Patent: July 10, 2001Assignee: Seco Tools ABInventors: Bo Jansson, Jan Qvick
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Patent number: 6143240Abstract: A method for making a high density powdered metal article is provided. In one embodiment, the composition consists of iron based powder, lubricant, graphite and ferro alloy additions. Satisfactory results may also be achieved by using fully prealloyed grades of metal powders, substantially pure powder blends, fully prealloyed powder blends, partially prealloyed powder blends and powder blends containing ferro alloys. The composition is compacted in rigid tools at ambient temperature, sintering at high temperature greater than 1100.degree. C. and then formed in rigid tools at 40 to 90 tons per square inch to a density greater than 94% of theoretical. The high density article is then annealed. The final article demonstrates remarkable mechanical properties which are atypical of powdered metal components and approach those of wrought steel.Type: GrantFiled: November 14, 1997Date of Patent: November 7, 2000Assignee: Stackpole LimitedInventors: Peter Jones, Roger Lawcock
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Patent number: 6077476Abstract: A method for operating a gas pressure vessel for use in hot isostatic pressing operations. This method includes heating and gas pressurizing an interior chamber of the vessel and thereafter simultaneously removing hot gas from this interior chamber and introducing cold gas to this interior chamber.Type: GrantFiled: October 23, 1998Date of Patent: June 20, 2000Assignee: Crucible Materials CorporationInventors: Michael D. Quinlan, Joseph F. Perez
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Patent number: 6071469Abstract: There is disclosed a method of sintering cemented carbide bodies including heating said bodies to the sintering temperature in a suitable atmosphere and cooling. If said cooling at least to below 1200.degree. C. is performed in a hydrogen atmosphere of pressure 0.4-0.9 bar and >0.1 bar noble gas, preferably argon cemented carbide bodies with no surface layer of binder phase are obtained. This is an advantage when said bodies are to be coated with wear resistant layers by the use of CVD-, MTCVD- or PVD-technique.Type: GrantFiled: May 6, 1999Date of Patent: June 6, 2000Assignee: Sandvik ABInventors: Barbro Rohlin, Margareta P.ang.lsson, Leif kesson
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Patent number: 6030507Abstract: A process for making a crystalline solid-solution powder which involves reacting at least two reactants in a plasma arc of a plasma chamber and blast-cooling the resultant product in a high velocity gas stream to form the powder. The first reactant is a molten metal alloy and the second reactant is a gas. The reaction is carried out in a plasma arc and the products rapidly cooled by a gas stream acting at the outlet opening of the plasma chamber. The crystalline solid-solution powder formed by the process has a low electrical resistivity. If an indium-tin alloy is used as the first reactant and oxygen as the second reactant, there is obtained an indium-tin-oxide (ITO) crystalline solid-solution powder which, when compacted to 40% of its theoretical density, has an electrical resistivity in the range of about 2 .OMEGA.cm. This ITO crystalline solid-solution powder is particularly suitable for preparing an ITO target, with high electrical conductivity and thus high achievable sputtering rates.Type: GrantFiled: May 14, 1998Date of Patent: February 29, 2000Assignee: W.C. Heraeus GmbH & Co. KGInventors: David Francis Lupton, Jorg Schielke, Marek Gorywoda, Bernard Serole, Friedhold Scholz
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Patent number: 6019937Abstract: A process of forming a sintered article of powder metal comprising blending graphite, Si carbide and lubricant, with pre-alloyed iron base powder; pressing said blended mixture to a shaped article; sintering said article in a reduced atmosphere; forced cooling said sintered article.Type: GrantFiled: November 27, 1998Date of Patent: February 1, 2000Assignee: Stackpole LimitedInventors: Rohith Shivanath, Karol Kucharski, Peter Jones
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Patent number: 5985207Abstract: A method of forming a refractory die, and a method for forming a metal article using a refractory die. The refractory die is formed of a ceramic material by casting a slurry containing particles of the ceramic material onto a mold. Then the mold is vibrated while excess liquid medium from the slurry is simultaneously removed, whereby ceramic particles continue to flow into surface details of the mold. The present method of forming a refractory die minimizes drying and firing shrinkage, and even adjusts for drying and firing shrinkage by inclusion of kyanite in the refractory die. According to the method of forming a metal article, a particulate material containing powdered metal is compressed on a refractory die at an elevated temperature and pressure. The consolidated particulate material is differentially cooled, wherein a first, low mass portion contacting the refractory die is cooled more quickly than an opposing, high mass portion of the consolidated body.Type: GrantFiled: April 21, 1997Date of Patent: November 16, 1999Inventor: Paul D. Vawter
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Patent number: 5930579Abstract: A method for manufacturing reduced iron briquettes, wherein reduced iron obtained by a direct reduction method is made into briquettes using a briquette machine, and whereafter the hot briquettes are subject to gradual cooling at a cooling rate in the range of 150.degree. C. to 250.degree. C. per minute using water spray. The reduced iron briquettes thus obtained are (a) less prone to breakage break during storage and transport; (b) less prone to degeneration into powder accompanying such breakages etc.; and (c) also display an excellent degree of metallization. Hence, the loss in weight during storage and transport can be reduced, and the harmful effects caused by dust to the transport vehicles, ships, loading/unloading equipment, and operators of the same can be reduced. Also, since the number of breakages is reduced, there is also a reduction in the amount of any re-oxidation of the reduced iron which tends to occur at newly exposed faces, whereby a product of more consistent quality can be obtained.Type: GrantFiled: October 27, 1995Date of Patent: July 27, 1999Assignee: Kabushiki Kaisha Kobe Seiko ShoInventors: Hiroshi Nagumo, Yutaka Inada, Yoshinori Kanno, Osamu Tsuge
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Patent number: 5882448Abstract: A contact material for a vacuum valve including, a conductive constituent including at least copper, an arc-proof constituent including at least chromium and an auxiliary constituent including at least one selected from the group consisting of tungsten, molybdenum, tantalum and niobium. The contact material is manufactured by quench solidification of a composite body of the conductive constituent, the arc-proof constituent and the anxiliary constituent.Type: GrantFiled: August 12, 1997Date of Patent: March 16, 1999Assignee: Kabushiki Kaisha ToshibaInventors: Tsuneyo Seki, Tsutomu Okutomi, Atsushi Yamamoto, Takashi Kusano
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Patent number: 5881354Abstract: A method of making a sintered article of powder metal having a carbon composition in the range of about 0.8% to 2.0% by weight, then spheroidizing the sintered article and then warm forming the sintered article at a temperature between 250.degree. and 700.degree. C. for a time duration selected to form the article to a final shape.Type: GrantFiled: May 3, 1996Date of Patent: March 9, 1999Assignee: Stackpole LimitedInventors: Rohith Shivanath, Peter Jones
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Patent number: 5858056Abstract: A metal sintered body composite material which can exhibit superior seizure resistance even when light metal is softened, and a method for producing the same. The production method uses iron base raw material powder including C and one of Cr, Mo, V, W, Mn, and Si, and comprises the steps of forming and sintering a powder compressed article so as to obtain a porous metal sintered body having a space lattice structure having pores, impregnating the pores of the porous metal sintered body with an aluminum alloy and solidifying the aluminum alloy, applying aging treatment by heating and holding the composite material at an aging treatment temperature range, whereby a metal constituting the porous metal sintered body has a micro-Vickers hardness of 200 to 800.Type: GrantFiled: March 15, 1996Date of Patent: January 12, 1999Assignee: Toyota Jidosha Kabushiki KaishaInventors: Manabu Fujine, Yoshiaki Kajikawa, Minoru Yamashita, Koji Saito
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Patent number: 5857139Abstract: The present invention relates to a process for preparing an electrode for secondary battery employing hydrogen-storage alloy systems, more specifically, to a process for preparing an anode material for secondary battery which can be charged/discharged in an electrolyte and has a high discharge efficiency and energy density per unit weight, by sintering a mixture of hydrogen-storage alloy systems. An electrode for secondary battery of the present invention is prepared by the process which comprises the steps of: (i) mixing a hydrogen-storage alloy powder free of Ni with a hydrogen-storage alloy powder containing Ni over 30 atomic %; (ii) cold-pressing the mixed powder at a pressure of 5 to 15 ton/cm.sup.2 ; (iii) sintering the cold-pressed mixture in a quartz tube at 900.degree. C. for 5 to 15 min under a vacuum condition of 10.sup.-2 to 10.sup.-3 torr; and, (iv) quenching the sintered material.Type: GrantFiled: April 25, 1996Date of Patent: January 5, 1999Assignee: Korea Advanced Institute of Science and TechnologyInventors: Jai-Young Lee, Ki-Young Lee, Han-Ho Lee, Dong-Myung Kim, Ji-Sang Yu, Jae-Han Jung, Soo-Geun Lee
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Patent number: 5856032Abstract: A cermet including a cermet core zone in which the content of a binder amounts to at most 90% by mass in relationship to a cermet hard phase is formed with a 0.01 to 3 um deep surface layer having an increased resistance to wear compare to the cermet core zone.Type: GrantFiled: September 30, 1996Date of Patent: January 5, 1999Assignee: Widia GmbHInventors: Hans Werner Daub, Klaus Dreyer
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Patent number: 5682588Abstract: The present invention relates to a method for producing, without quench-hardening process, a ferrous sintered alloy having satisfactory strength which is equal to that of the conventional ferrous sintered quenched material, and the method comprises the steps of: preparing a powder mixture by adding, in weight ratios, 1 to 2% of copper powder, 1 to 3% of Ni powder, and graphite to a ferrous alloy powder consisting of 3 to 5% of Ni, 0.4 to 0.7% of Mo, and the remainder Fe, the quantity of said graphite being determined such that the C-content after sintering is 0.2 to 0.7%; compacting said powder mixture in a tool to form a green compact; sintering said green compact in a non-oxidizing atmosphere at a temperature in the range of 1130.degree. to 1230.degree. C.; and cooling the sintered product in the sintering furnace at a rate of 5.degree. C./min. to 20.degree. C./min.Type: GrantFiled: September 23, 1996Date of Patent: October 28, 1997Assignees: Hitachi Powdered Metals Co., Ltd., Hitachi Koki Co., Ltd.Inventors: Tadayuki Tsutsui, Kei Ishii, Hideo Shikata, Sumihisa Kotani
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Patent number: 5666634Abstract: The invention has for its object the provision alloy steel powders for Cr-based high strength sintered bodies having high tensile strength, fatigue strength and toughness which are adapted for use in parts for motor vehicles and parts for OA apparatus.The composition of the alloy steel powder comprises, by wt %, not larger than 0.1% of C, not larger than 0.08% of Mn, 0.5-3% of Cr, 0.1-2% of Mo, not larger than 0.01% of S, not larger than 0.01% of P, not larger than 0.2% of O, optionally one or more of 0.2.about.2.5% Ni, 0.5.about.2.5% Cu and the balance being inevitable impurities and Fe. The sintered body has substantially the same composition provided that the content of C alone is limited to 0.2-1.2%.The manufacturing method comprises molding the above alloy steel powder, sintering the resulting green compact at a temperature of 1100.degree.-1300.degree. C. and immediately cooling at a cooling rate of 10.degree.-200.degree. C./minute.Type: GrantFiled: December 23, 1994Date of Patent: September 9, 1997Assignee: Kawasaki Steel CorporationInventors: Shigeru Unami, Osamu Furukimi
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Patent number: 5666632Abstract: A two layer valve seat insert and a method for its manufacture is described. The method comprises the steps of preparing two powder mixtures; a first powder mixture for forming the valve seat face layer; a second powder mixture for forming the valve seat base layer; sequentially introducing a predetermined quantity of each of said first and said second powder mixtures into a powder compacting die and having an interface therebetween substantially perpendicular to the axis of said die; simultaneously compacting said first and said second powder mixtures to form a green compact having two layers and sintering said green compact, wherein at least one of the chemical composition or the physical characteristics of at least one of said first and said second powder mixtures is adjusted so as to result in said valve seat face layer and said valve seat base layer having substantially the same density after compaction.Type: GrantFiled: June 12, 1996Date of Patent: September 9, 1997Assignee: Brico Engineering LimitedInventor: Paritosh Maulik
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Patent number: 5649279Abstract: There is disclosed a new process for binder phase enrichment. The process combines binder phase enrichment by dissolution of cubic phase with the requirements that cause formation of stratified layers, resulting in a unique structure. The new structure is characterized by, in comparison with the ones previously known, deeper stratified layers and less maximum binder phase enrichment. The possibility of combining dissolution of the cubic phase with formation of stratified layers offers new possibilities to optimize the properties of tungsten carbide based cemented carbides for cutting tools.The new process offers possibilities to combine the two types of gradients. The dissolution of cubic phase moves the zone with maximum mount of stratified binder phase from the surface to a zone close to and below the dissolution front.Type: GrantFiled: November 17, 1994Date of Patent: July 15, 1997Assignee: Sandvik ABInventors: Per Gustafson, Leif Akesson, Ake Ostlund
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Patent number: 5649280Abstract: A method of high retained strain forging is described for Ni-base superalloys, particularly those which comprise a mixture of .gamma. and .gamma.' phases, and most particularly those which contain at least about 30 percent by volume of .gamma.'. The method utilizes an extended subsolvus anneal to recrystallize essentially all of the superalloy and form a uniform, free grain size. Such alloys may also be given a supersolvus anneal to coarsen the grain size and redistribute the .gamma.'. The method permits the manufacture of forged articles having a fine grain size in the range of about ASTM 5-12 (5-60 .mu.m).Type: GrantFiled: January 2, 1996Date of Patent: July 15, 1997Assignee: General Electric CompanyInventors: Charles Philip Blankenship, Michael Francis Henry, Eric Scott Huron, John Michael Hyzak
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Patent number: 5628045Abstract: A process for producing sintered parts with high wear resistance and good dynamic strength properties from formed bodies, which have been pressed as green parts from a completely-alloyed air-hardened heat-treatment steel powder with a carbon content of at least 0.3% added in the form of graphite. The process includes sintering the parts under protective gas at a sintering temperature of at least 1000.degree. C. and subsequent cooling. The sintered parts are cooled immediately after sintering from the sintering temperature to a first holding temperature in the range of Ar.sub.3 to a maximum of 150.degree. C. above Ar.sub.3 and are held for a first holding period of 5 to 25 minutes at this temperature (austenitizing phase). Immediately after this, the sintered parts are cooled in accelerated fashion to a second holding temperature by convective gas cooling and are held at this temperature for a second holding period.Type: GrantFiled: June 7, 1996Date of Patent: May 6, 1997Assignees: Mannesmann Aktiengesellschaft, BT Magnet-Technologie GmbHInventors: Karl-Heinz Lindner, Rudolf Schneider
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Patent number: 5603072Abstract: Fe-based alloy powder suitable for manufacturing sintered products with excellent corrosion resistance for example, which comprises by weight percentage of not more than 0.03% of C; not more than 2% of Si; not more than 0.5% of Mn; from 8 to 28% of Ni; from 15 to 25% of Cr; from 3 to 8% of Mo; optionally at least one of not more than 5% of Cu; not more than 3 % of Sn; not more than 2% of Nb and not more than 2% of Ti; and the balance being Fe and incidental impurities. The Fe-based alloy powder is sintered in an inert gas such as Ar or H.sub.2, or in an atmosphere of N.sub.2 with pressure of 1 to 10 torr after being compacted. A sintered compact sintered in an atmosphere of N.sub.2 with pressure of higher than 10 torr and not higher than 200 torr is cooled at cooling rate of higher than 50.degree. C./min.Type: GrantFiled: November 14, 1994Date of Patent: February 11, 1997Assignee: Daido Tokushuko Kabushiki KaishaInventors: Tomio Kouno, Mitsuaki Asano
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Patent number: 5516483Abstract: A process of forming a sintered article for powder metal comprising blending carbon and ferro alloys and lubricant with compressible elemental iron powder, pressing said blended mixture to form sintering said article, and then high temperature sintering said article in a reducing atmosphere to produce a sintered article having a high density from a single compression.Type: GrantFiled: February 8, 1994Date of Patent: May 14, 1996Assignee: Stackpole LimitedInventors: Rohith Shivanath, Peter Jones, Danny T. D. Thieu
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Patent number: 5476632Abstract: A process of forming a sintered article of powder metal comprising: selecting elemental iron powder; determining the desired properties of said sintered article and selecting, a quantity of carbon, and ferro alloy from the group of ferro manganese, ferro chromium, ferro molybdenum, ferro vanadium, ferro silicon and ferro boron; grinding said ferro alloy to a mean particle size of approximately 8 to 12 microns; introducing a lubricant while blending the carbon, ferro alloy, with said elemental iron powder; pressing the mixture to form the article; and then high temperature sintering the article at a temperature between 1,250.degree. C. and 1,350.degree. C. in a neutral or reducing atmosphere; so as to produce the sintered article of powdered metal; and includes the product formed thereby.Type: GrantFiled: January 14, 1994Date of Patent: December 19, 1995Assignee: Stackpole LimitedInventors: Rohith Shivanath, Peter Jones
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Patent number: 5466414Abstract: A process for fabrication of sintered metal components having improved mechanical, physical and wear-resistent properties.Type: GrantFiled: September 1, 1994Date of Patent: November 14, 1995Assignee: TecSyn, Inc.Inventor: Bjorn O. A. Pettersson
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Patent number: 5466276Abstract: A secondary hardening type high temperature wear-resistant sintered alloy body comprising 0.4 to 15 wt. % of at least one species of metal carbide forming element which is selected from the group consisting of W, Mo, V, Ti, Nb, Ta and B; 5 to 35 wt. % of at least one species of austenite forming element which is selected from the group consisting of Ni, Co, Cu, and Cr; 0.2 to 1.2 wt. % of C; and 0.04 to 0.2 wt. % of Al consisting essentially the remainder of Fe, wherein the alloy body contains an austenite phase which is capable of martensitic transformation.Type: GrantFiled: July 7, 1993Date of Patent: November 14, 1995Assignees: Honda Giken Kogyo Kabushiki Kaisha, Nippon Piston Ring Co., Ltd.Inventors: Katsuaki Sato, Katsuhiko Tominaga, Tsutomu Saka, Osamu Kawamura, Teruo Takahashi, Arata Kakiuchi
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Patent number: 5462917Abstract: A superconductor material having a current density, J, of from about 30,000 to about 85,000 amps/cm.sup.2 at zero magnetic field and 77.degree. K is disclosed. The 123 superconductor, of the formula L.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. wherein L is preferably yttrium, is capable of entrapping sufficiently high magnetic fields and exhibits a low microwave surface resistance. The process of preparing the superconductor comprises compacting the bulk product, L.sub.1 Ba.sub.2 Cu.sub.3 O, and then sintering the reaction product at a temperature between about 40.degree. C. to about 90.degree. C. below its melting point, i.e., for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. at a temperature of approximately 940.degree. C. The composition is then heated in a preheated chamber maintained at approximately 1090.degree. C. to about 1,200.degree. C. (approximately 1,100.degree. C. for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta.Type: GrantFiled: February 14, 1994Date of Patent: October 31, 1995Assignee: University of Houston-University ParkInventors: Kamel Salama, Venkatakrishnan Selvamanickam
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Patent number: 5453243Abstract: A process for producing titanium aluminide weld rod comprising: attaching one end of a metal tube to a vacuum line; placing a means between said vacuum line and a junction of the metal tube to prevent powder from entering the vacuum line; inducing a vacuum within the tube; placing a mixture of titanium and aluminum powder in the tube and employing means to impact the powder in the tube to a filled tube; heating the tube in the vacuum at a temperature sufficient to initiate a high-temperature synthesis (SHS) reaction between the titanium and aluminum; and lowering the temperature to ambient temperature to obtain a intermetallic titanium aluminide alloy weld rod.Type: GrantFiled: August 17, 1994Date of Patent: September 26, 1995Assignee: The United States of America as represented by the Secretary of the InteriorInventors: Jeffrey S. Hansen, Paul C. Turner, Edward R. Argetsinger
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Patent number: 5403542Abstract: Method of manufacturing a sintered carbonitride alloy comprising wet milling powders of forming binder phase containing Co, Ni and mixture thereof and powder forming hard constituents of nitrides and carbonitrides with Ti as the main component to a mixture with desired composition; compacting said mixture to form compact; heating the compact at 100-300 C. in oxygen or air and subjecting said compact in multiple heating steps to effect sintering.Type: GrantFiled: February 10, 1994Date of Patent: April 4, 1995Assignee: Sandvik ABInventors: Gerold Weinl, Rolf G. Oskarsson, Per Gustafsson
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Patent number: 5382405Abstract: A method of manufacturing a shaped article from a powdered precursor, wherein the components of the powdered precursor are subjected to a self-propagating high-temperature synthesis (SHS) reaction and are consolidated essentially simultaneously. The shaped article requires essentially no machining after manufacture.Type: GrantFiled: September 3, 1993Date of Patent: January 17, 1995Assignee: Inland Steel CompanyInventors: Kenneth F. Lowrance, II, Eric C. Knorr, William M. Goldberger, Daniel Boss, Doreen Edwards
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Patent number: 5371049Abstract: A ceramic composite is disclosed which may be used as lightweight armor or for other impact or wear resisting purposes. The ceramic composite may comprise distinct phases of AlN and SiC; may be a solid solution of SiC; or may contain AlN or SiC, or both AlN and SiC as residual phase(s) in a solid solution matrix of SiC and AlN.Type: GrantFiled: January 9, 1989Date of Patent: December 6, 1994Assignee: FMC CorporationInventors: Keith R. Moffett, John D. Morrow
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Patent number: 5354536Abstract: A silicon carbide material is made following a procedure including hot pressing to provide a finished product having a microstructure with an optimal grain size of less than 7 micrometers. The material exhibits a dominant failure mode of intergranular fracture requiring significant energy for crack propagation. The method of manufacturing is cost-effective by allowing the use of "dirty" raw materials since the process causes impurities to segregate at multi-grain boundary junctions to form isolated pockets of impurities which do not affect the structural integrity of the material. End uses include use as protective projectile-resistant armor.Type: GrantFiled: September 3, 1993Date of Patent: October 11, 1994Assignee: Cercom Inc.Inventor: Andre Ezis
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Patent number: 5310605Abstract: A process for producing a ceramic-metal composite body exhibiting binder enrichment and improved fracture toughness at its surface. The process involves forming a shaped body from a homogeneous mixture of: (a) about 2-15 w/o Co or about 2-12 w/o Ni binder, (b) excess carbon, (c) optionally, 0 to less than 5.0 v/o B-1 carbides, and (d) remainder tungsten carbide. The mixture contains sufficient total carbon to result in an ASTM carbon porosity rating of C06 to C08 at the core of the densified body. The weight ratio of excess carbon to binder is about 0.05:1 to 0.037:1. The shaped body is densified in a vacuum or inert atmosphere at or above about 1300.degree. C. and slow cooled, at least to about 25.degree. below the eutectic temperature. Alternatively, the sintered body may be cooled to a holding temperature at or slightly above the eutectic temperature, isothermally held for at least 1/2 hr, and further cooled to ambient.Type: GrantFiled: August 25, 1992Date of Patent: May 10, 1994Assignee: Valenite Inc.Inventors: J. Gary Baldoni, II, Stephen L. Bennett
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Patent number: 5290508Abstract: The present invention relates to a manufacturing process for ring-shaped parts having high wear resistance and mechanical strength. Raw material powder containing (weight %) C at 0.4-0.9%, Ni at 1.5-4.0%, Mo 0.2-0.6%, and a remainder consisting of Fe and unavoidable impurities, is compacted and shaped, thereafter sintered and forged; obtained sintered body is hardened by heating at a temperature within a range of 800.degree.-950.degree. C., thereafter high temperature tempering is carried out for 20-60 minutes at a temperature within a range of 570.degree.-700.degree. C.; then the surface layer of the inner periphery and/or outer periphery of said sintering body is heated; then if required, low temperature tempering (temper process) is carried out at a temperature within a range of 160.degree.-220.degree. C.Type: GrantFiled: April 7, 1992Date of Patent: March 1, 1994Assignee: Mitsubishi Materials CorporationInventors: Kazuya Kobayashi, Shigeyoshi Nagahara, Hikaru Hosono
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Patent number: 5162099Abstract: The process serves for producing a carbon-containing sintered compact from steel powder. In this process, the steel powder is heated to sintering temperature in an atmosphere containing, at least for a time, carbon monoxide, is kept at sintering temperature over a predetermined period of time and the sintered compact formed thereby is subsequently cooled.In this process, the carbon content of the sintered compact to be produced is to be set to a predetermined value in a way which is simple and suitable for mass production.This is achieved by the partial pressure of the carbon monoxide in the atmosphere being changed selectively during the execution of the production process, and by this change being controlled in such a way that the carbon content of the sintered compact is set to the predetermined value after execution of the production process.Type: GrantFiled: March 3, 1992Date of Patent: November 10, 1992Assignee: Asea Brown Boveri Ltd.Inventors: Gundolf Meyer, Christoph Tonnes
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Patent number: 5147446Abstract: A method of producing a dense compact of ultra-fine powder employs low temperatures and high pressures to produce a very dense, nearly ideally packed compact from a starting nano-sized powder. The final product is capable of being easily hot-pressed or sintered to full density.Type: GrantFiled: August 6, 1991Date of Patent: September 15, 1992Assignee: The United States of America as represented by the Secretary of the CommerceInventors: Alexander Pechenik, Gasper J. Piermarini
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Patent number: 5147601Abstract: A composition comprising a powder of iron and nickel and a binder (e.g. wax) is injection molded. The powder contains 0.5 to 10% by weight of nickel and has an average particle diameter not exceeding 45 microns. The binder is removed from the molded product. The molded product is sintered, and the sintered product is cooled to room temperature slowly at a rate of 2.degree. C. to 50.degree. C. per minute. The sintered product is of an iron-nickel alloy, has a high density and a high level of soft ferromagnetic properties, and may be complicated in shape.Type: GrantFiled: March 30, 1992Date of Patent: September 15, 1992Assignee: Sumitomo Metal Mining Co., Ltd.Inventors: Akihito Ohtsuka, Yoshio Kijima
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Patent number: 5145505Abstract: Disclosed are a high toughness cermet comprising a sintered alloy comprising 75 to 95% by weight of a hard phase of carbide, nitride or carbonitride containing Ti, at least one of W, Mo and Cr, and N and C, and the balance of a binder phase composed mainly of an iron group metal, and inevitable impurities,wherein the content of Ti in said sintered alloy is 35 to 85% by weight calculated on TiN or TiN and TiC, and the contents of W, Mo and Cr are 10 to 40% by weight in total calculated on WC, Mo.sub.2 C and/or Cr.sub.3 C.sub.2,the relative concentration of said binder phase at the 0.01 mm-inner portion from the surface of said sintered alloy is 5 to 50% of the average binder phase concentration of the inner portion, and the relative concentration of said binder phase at the 0.1 mm-inner portion from the surface of said sintered alloy is 70 to 100% of the average binder phase concentration of the inner portion, anda compression stress of 30 kgf/mm.sup.Type: GrantFiled: February 7, 1992Date of Patent: September 8, 1992Assignee: Toshiba Tungaloy Co., Ltd.Inventors: Takeshi Saito, Kozo Kitamura, Mitsuo Ueki
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Patent number: 5118289Abstract: A hot-isostatic press adapted for rapid cooling of the hot zone after completed pressing and sintering of the material includes a pressure vessel, end closures, and a hot zone surrounded by thermal barriers. Between the thermal barriers and the pressure vessel with end closures there are colder spaces. At least one connection, located in the lower part of the thermal barrier and provided with a valve between the space next to the pressure vessel and the space below the bottom thermal barrier, is provided with an externally controllable valve. In the upper part of the thermal barrier there is an opening with a relatively large cross section and a valve is provided for the opening, which comprises a heat-insulated portion.Type: GrantFiled: January 11, 1991Date of Patent: June 2, 1992Assignee: Asea Brown Bovari ABInventors: Carl Bergman, Lars Ohlsson
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Patent number: 5110542Abstract: The present invention describes a process for the compaction and densification of materials using heat and high pressure in which pressure is applied isostatically to the workpiece to be compacted, heat is applied to the pressurized workpiece as rapidly as feasible, effecting thereby full compaction and densification. Heating is terminated and the workpiece cooled while the workpiece is still pressurized. This process effects hot-isostatic-processing of workpieces while reducing the time such workpieces spend at elevated temperatures. The resulting parts can have novel structures, properties or compositions not obtained with other processing procedures.Type: GrantFiled: March 4, 1991Date of Patent: May 5, 1992Assignee: Vital Force, Inc.Inventor: Robert M. Conaway