US3181947A - Powder metallurgy processes and products - Google Patents

Powder metallurgy processes and products Download PDF

Info

Publication number
US3181947A
US3181947A US204055A US20405562A US3181947A US 3181947 A US3181947 A US 3181947A US 204055 A US204055 A US 204055A US 20405562 A US20405562 A US 20405562A US 3181947 A US3181947 A US 3181947A
Authority
US
United States
Prior art keywords
metal
particles
oxide
titanium
metal oxide
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US204055A
Inventor
Vordahl Milton Bernard
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Crucible Steel Company of America
Original Assignee
Crucible Steel Company of America
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US634156A external-priority patent/US3066391A/en
Application filed by Crucible Steel Company of America filed Critical Crucible Steel Company of America
Priority to US204055A priority Critical patent/US3181947A/en
Application granted granted Critical
Publication of US3181947A publication Critical patent/US3181947A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
    • C22C32/001—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides
    • C22C32/0015—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides with only single oxides as main non-metallic constituents
    • C22C32/0031—Matrix based on refractory metals, W, Mo, Nb, Hf, Ta, Zr, Ti, V or alloys thereof
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S75/00—Specialized metallurgical processes, compositions for use therein, consolidated metal powder compositions, and loose metal particulate mixtures
    • Y10S75/95—Consolidated metal powder compositions of >95% theoretical density, e.g. wrought
    • Y10S75/951—Oxide containing, e.g. dispersion strengthened

Definitions

  • a primary object of the invention is to provide materials of such chemically reactive metals in the manner above referred to which possess superior hot strength properties as compared to those of these same metals as produced in massive form directly from an initially molten state.
  • this is accomplished by reducing the metal to an extremely fine particle size, ordinarily on the order of 1' to 2 microns, more or less, in mean minimum dimension, applying to each particle a thin, coating of a stable metal oxide, and thereupon consolidating by pressing and sintering.
  • finely powdered aluminum upon air heating to develop an oxide coating on each particle followed by pressing, sintering and working, results in a material of greatly enhanced strength, creep and fatigue resistance at elevated temperatures as compared to the aluminum metal itself as obtained, for example, by casting from the molten state.
  • the useful service temperature of aluminum is thus raised from ZOO-400 F. to about 600-800 F.
  • Sintered oxidized aluminum powder thus has much higher elevated temperature strength than does aluminum itself or any of its wrought and cast alloys. Worked shapes of the material have some residual ductility-enough to be definitely useful.
  • the oxide coating in each particle breaks up into small, discrete platelets which distribute themselves like fence pickets about the particles, leaving the intervening portions of the aluminum particles exposed to each other to be Welded together and coalesced by the pressing, sintering and subsequent hot and/ or cold working operations.
  • the oxide platelets prevent recrystallization of the small aluminum particles, thus preventing grain growth from particle-to-particle, thereby retaining the original microstructure.
  • the slip shear strength is thus increased as compared to that of massive aluminum as produced from the molten state. This latter on cooling produces relatively large crystals, which reduce the slip shear strength, for this reason and presumably also for the reason that the recrystallization probably re- 3,181,947 Patented May 4, 1965 moves some voids between crystals thus further reducing the slip shear strength.
  • the titanium or zirconium particles with. a metal oxide other than an oxide of the base metal particle, which oxide is insoluble in the metal at sintering temperatures.
  • the metal oxide with which the titanium particles, for example, are coated must be one which is stable in contact with titanium at the elevated temperature. That is to say, the metal oxide must not decompose thus providing oxygen for combination with titanium at the elevated temperature.
  • the oxides of calcium, magnesium, beryllium and thorium fulfill both stability and insolubility requirements for use with titanium and zirconium and base alloys of these metals, and may be employed individually or in admixture in the present invention. Certain of the rare earth oxides also exhibit the necessary characteristics required of the metal particle coating. Gadolinium, for example, is entirely astisfactory. However, for economic reasons the alkaline earth metal oxides mentioned and thorium oxide will generally be employed.
  • the particles of the base metal are very finely divided, preferably having a mean minimum dimension of the order of about 12 microns or less.
  • the particles of metal oxide must have a mean maximum diameter substantially less than the mean diameter of the metal particles.
  • the metal oxide particles should be of the order of about ten times smaller than the metal powder. Colloidal suspensions of the coating materials provide an excellent source of the metal oxide in a sufficiently fine state of subdivision.
  • Coating may be effected by agitating the base metal powder in a colloidal suspension.
  • the suspending liquid is drawn off and the thus coated metal powder dried, after which it is consolidated by pressing and sintering.
  • the so-coated particles are'consolidated into an integral composition by con current pressing at about 5000 to 10,000 p.s.i. at sintering temperatures of about 1300-2000 F., and preferably at about 1400-1700 F. over a period of about 5 to 25 hours.
  • pressing and sintering may be carried out as separate steps, in which case, the coated metal powder isfirst consolidated by cold pressing, re-
  • titanium or a titanium base alloy for example, titanium or a titanium base alloy.
  • the mixture is thereupon dried with accompanying continuous agitation, and the residual salt of the preci itating agent leached out with a non-aqueous solvent.
  • the bound water in the particle coating is then drawn off by heating in a vacuum, and the coated metal powder thus obtained is ready for use in the production of pressed and sintered powder metallurgy products in accordance with the invention.
  • the metal oxide in an extremely fine state of subdivision in the form of a dry powder may be thoroughly admixed with the base metal powder as by ball milling or tumbling, and the resulting mixture pressed and sintered as aforesaid.
  • This thorough admixing coats the base metal particles with the finely divided metal oxide in a loosely adherent manner, which, however, functions in the same manner as the colloidally applied coating to provide powder metallurgy products of improved high temperature properties on subsequent pressing, sintering and working.
  • magnesia or one or more of the other metal oxides above referred to may be ball milled, either dry or in admixture with a liquid such as alcohol, a liquid hydrocarbon, or even cold water, provided steps are taken to rid the hydrate formed of its water which would be strongly bound.
  • a liquid such as alcohol, a liquid hydrocarbon, or even cold water
  • the ball milling is continued until the coating of the finely divided metal oxide is produced upon the metal particles or until the metal oxide is reduced to a state of subdivision fine enough to coat the metal particles more or less continuously.
  • titanium for example, is added and the ball milling continued until microscopic examination reveals that the base metal particles have acquired a more or less continuous coating of the metal oxide.
  • the coating metal oxide when reduced to a sufl'iciently fine state of subdivision will adhere to the base metal particles sufiiciently well to permit removal of the excess metal oxide by screening or blowing.
  • the excess slurry is drained off following coating of the base metal particles, and the residual mass dried, whereupon excess coating powder is removed by screening or blowing as aforesaid.
  • the material thus obtained is ready for use in the production of pressed and sintered products. If the liquid medium employed is water, a final drying is effected by mild heating in a vacuum prior to consolidation.
  • the concentration of metal oxide in the finished sintered product should be such that the product does not contain more than about 20% by weight oxygen, and preferably less than 20% by weight oxygen.
  • the process which comprises: applying to finely divided particles of a metal selected from the group consisting of titanium, zirconium and base alloys of said metals, a surface coating of a metal oxide which is stable in contact with and substantially insoluble in said metal at sintering temperatures, and consolidating the so-coated particles into an integral mass with the application of pressure and heat at sintering temperatures.
  • the process which comprises: applying to finely divided particles of metal selected from the group consisting of titanium, zirconium and base alloys of said metals, a surface coating of metal oxide particles of maximum dimension substantially less than the minimum dimension of said metal particles and selected from the group consisting of the oxides of calcium, magnesium, beryllium, thorium, gadolinium and mixtures thereof, and consolidating the so-coated particles into an integral mass by application of pressure and heat at sintering temperatures.
  • the process which comprises: thoroughly admixing finely divided particles of a metal of the group consisting of titanium, zirconium and base alloys of said metals with particles of an oxide of a metal selected from the group consisting of calcium, magnesium, beryllium, thorium, gadolinium and mixtures thereof more finely divided than said metal particles, whereby said metal particles are individually coated with said metal oxide, separating said coated metal particles from non-adhering metal oxide, and thereupon consolidating the so-coated particles by application of pressure and heat at sintering temperatures.
  • the process which comprises: thoroughly admixing particles of a metal of the group consisting of titanium, zirconium and base alloys of each having a mean dimension of the order of 1-2 microns with particles of an oxide of a metal selected from the group consisting of calcium, magnesium, beryllium, thorium, gadolinium and mixtures thereof, said metal oxide particles having a maximum dimension less than about one-tenth that of said metal particles, whereby said metal particles are individually coated with said metal oxide particles, separating the coated particles from non-adhering metal oxide particles and thereupon applying pressure at sintering temperatures, whereby said so-coated particles are consolidated.
  • the process which comprises: thoroughly admixing finely divided particles of a metal of the group consisting of titanium, zirconium and base alloys of said metals with particles of an oxide of a metal selected from the group consisting of calcium, magnesium, beryllium, thorium,
  • a process for the production of a sintered compact which comprises: thoroughly admixing particles of a metal selected from the group consisting of titanium, zirconium and base alloys of each having a mean dimension not greater than about two microns with particles of a metal oxide characterized by substantial insolubility in said metal and thermal stability in the presence of said metal at the sintering temperature, said oxide particles having a mean maximum dimension substantially smaller than that of said metal particles, whereby said metal particles are individually coated with said oxide, and thereupon consolidating the so-coated particles by application of pressure and heat at the sintering temperature in an atmosphere which is inert with respect to said metal.
  • a process for the production of a sintered compact which comprises: thoroughly admixing particles of a metal selected from the group consisting of titanium, zirconium and base alloys of each having a mean dimension not greater than about two microns with particles of a metal oxide characterized by substantial insolubility in said metal and thermal stability in the presence of said References Cited in the file of this patent UNITED STATES PATENTS 2,431,660 Gaudenzi Nov. 25, 1947

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)

Description

United States Patent ice 7 Claims. c1. 75-206) This invention pertains to the art of powder metallurgy, more especially as applied to metals which are highly reactive chemically, such as titanium, zirconium and base alloys of each, and to new materials of superior characteristics formed thereof and processes for producing the same by novel powder metallurgy techniques.
A primary object of the invention is to provide materials of such chemically reactive metals in the manner above referred to which possess superior hot strength properties as compared to those of these same metals as produced in massive form directly from an initially molten state.
In accordance with the basic procedure of the invention this is accomplished by reducing the metal to an extremely fine particle size, ordinarily on the order of 1' to 2 microns, more or less, in mean minimum dimension, applying to each particle a thin, coating of a stable metal oxide, and thereupon consolidating by pressing and sintering.
As is now well known, finely powdered aluminum upon air heating to develop an oxide coating on each particle followed by pressing, sintering and working, results in a material of greatly enhanced strength, creep and fatigue resistance at elevated temperatures as compared to the aluminum metal itself as obtained, for example, by casting from the molten state. The useful service temperature of aluminum is thus raised from ZOO-400 F. to about 600-800 F. Sintered oxidized aluminum powder thus has much higher elevated temperature strength than does aluminum itself or any of its wrought and cast alloys. Worked shapes of the material have some residual ductility-enough to be definitely useful.
The reason for this is not too well understood. One explanation is that by starting with aluminum in fine particle size of the order aforesaid and applying to each particle a thin oxide coating, as by heating in air, and thereupon consolidating by pressing, sintering and working, the oxide coating in each particle breaks up into small, discrete platelets which distribute themselves like fence pickets about the particles, leaving the intervening portions of the aluminum particles exposed to each other to be Welded together and coalesced by the pressing, sintering and subsequent hot and/ or cold working operations. The oxide platelets, however, prevent recrystallization of the small aluminum particles, thus preventing grain growth from particle-to-particle, thereby retaining the original microstructure. The slip shear strength is thus increased as compared to that of massive aluminum as produced from the molten state. This latter on cooling produces relatively large crystals, which reduce the slip shear strength, for this reason and presumably also for the reason that the recrystallization probably re- 3,181,947 Patented May 4, 1965 moves some voids between crystals thus further reducing the slip shear strength.
It has been attempted to produce analogous results with titanium powder, using controlled oxidation, nitriding or carburizing, to produce a skin or adherent coating on each powder particle. Since, however, extremely fine powders must be used, if at sintering temperatures any diffusion occurs, a homogeneous alloy will result and the purpose defeated. Unfortunately, the oxide, nitride and carbide of titanium are readily soluble in titanium and diffuse rapidly into the metal at minimum sintering temperatures of about 1300-l400 F. Instead of sintering to an adherent mixture with properties governed by the duplex structure, the composite homogenizes at least in part and a normal alloy results. The methods applicable to finely divided aluminum are thus not satisfactory when applied to powdered metals such as titanium, zirconium and base alloys of those metals.
In accordance with the present invention, it is proposed to coat the titanium or zirconium particles with. a metal oxide other than an oxide of the base metal particle, which oxide is insoluble in the metal at sintering temperatures. Furthermore, the metal oxide with which the titanium particles, for example, are coated must be one which is stable in contact with titanium at the elevated temperature. That is to say, the metal oxide must not decompose thus providing oxygen for combination with titanium at the elevated temperature.
The oxides of calcium, magnesium, beryllium and thorium fulfill both stability and insolubility requirements for use with titanium and zirconium and base alloys of these metals, and may be employed individually or in admixture in the present invention. Certain of the rare earth oxides also exhibit the necessary characteristics required of the metal particle coating. Gadolinium, for example, is entirely astisfactory. However, for economic reasons the alkaline earth metal oxides mentioned and thorium oxide will generally be employed.
The particles of the base metal are very finely divided, preferably having a mean minimum dimension of the order of about 12 microns or less. In order to assure the requisite coating of the finely divided metal, the particles of metal oxide must have a mean maximum diameter substantially less than the mean diameter of the metal particles. To produce a substantially continuous coating on the metal particles, the metal oxide particles should be of the order of about ten times smaller than the metal powder. Colloidal suspensions of the coating materials provide an excellent source of the metal oxide in a sufficiently fine state of subdivision.
Coating may be effected by agitating the base metal powder in a colloidal suspension. When coating has been efiected, the suspending liquid is drawn off and the thus coated metal powder dried, after which it is consolidated by pressing and sintering. The so-coated particles are'consolidated into an integral composition by con current pressing at about 5000 to 10,000 p.s.i. at sintering temperatures of about 1300-2000 F., and preferably at about 1400-1700 F. over a period of about 5 to 25 hours. Alternatively, pressing and sintering may be carried out as separate steps, in which case, the coated metal powder isfirst consolidated by cold pressing, re-
3 quiring about 75,000 to 125,000 p.s.i., followed by sintering in the temperature range aforesaid.
Because of the ready solubility of nitrogen and oxygen in the base metal, sintering is effected in an atmosphere not containing appreciable quantities of these elements, in order to obtain maximum uniformity of properties in the sintered product. Preferably, the atmosphere is inert with respect to titanium, for example, as argon. The method of the present invention thus departs from the teachings of the sintered aluminum powder metallurgy art wherein the aluminum particles with a surface coating of aluminum oxide are sintered in an oxidizing atmosphere. The problem of solubility of surface metal oxide coating is not encountered in the aluminum powder metallurgy art.
der, for example, titanium or a titanium base alloy. The
mixture is thereupon dried with accompanying continuous agitation, and the residual salt of the preci itating agent leached out with a non-aqueous solvent. The bound water in the particle coating is then drawn off by heating in a vacuum, and the coated metal powder thus obtained is ready for use in the production of pressed and sintered powder metallurgy products in accordance with the invention.
In accordance with another modification, the metal oxide in an extremely fine state of subdivision in the form of a dry powder may be thoroughly admixed with the base metal powder as by ball milling or tumbling, and the resulting mixture pressed and sintered as aforesaid. This thorough admixing coats the base metal particles with the finely divided metal oxide in a loosely adherent manner, which, however, functions in the same manner as the colloidally applied coating to provide powder metallurgy products of improved high temperature properties on subsequent pressing, sintering and working.
Thus, for example, magnesia or one or more of the other metal oxides above referred to may be ball milled, either dry or in admixture with a liquid such as alcohol, a liquid hydrocarbon, or even cold water, provided steps are taken to rid the hydrate formed of its water which would be strongly bound. With any of these modifications the ball milling is continued until the coating of the finely divided metal oxide is produced upon the metal particles or until the metal oxide is reduced to a state of subdivision fine enough to coat the metal particles more or less continuously. At this juncture, titanium, for example, is added and the ball milling continued until microscopic examination reveals that the base metal particles have acquired a more or less continuous coating of the metal oxide. The coating metal oxide when reduced to a sufl'iciently fine state of subdivision will adhere to the base metal particles sufiiciently well to permit removal of the excess metal oxide by screening or blowing. In the event ball milling is carried out in a liquid medium, the excess slurry is drained off following coating of the base metal particles, and the residual mass dried, whereupon excess coating powder is removed by screening or blowing as aforesaid. The material thus obtained is ready for use in the production of pressed and sintered products. If the liquid medium employed is water, a final drying is effected by mild heating in a vacuum prior to consolidation.
It is difficult to prescribe the ultimate thickness of the metal oxide coating because of the permissible variation of particle size and the starting metal oxide itself. Similarly, it is equally diificult to specify weight ratios of metal to metal oxide powder. However, it is sufiicient to '3- say that the concentration of metal oxide in the finished sintered product should be such that the product does not contain more than about 20% by weight oxygen, and preferably less than 20% by weight oxygen.
This application is a divisional application of my copending application for United States Letters Patent Serial No. 634,156, filed January 15, 1957, now Patent No. 3,066,391 which is a continuation-in-part of my application Serial No. 420,440, filed April 1, 1954, now abandoned.
I claim:
1. The process which comprises: applying to finely divided particles of a metal selected from the group consisting of titanium, zirconium and base alloys of said metals, a surface coating of a metal oxide which is stable in contact with and substantially insoluble in said metal at sintering temperatures, and consolidating the so-coated particles into an integral mass with the application of pressure and heat at sintering temperatures.
2. The process which comprises: applying to finely divided particles of metal selected from the group consisting of titanium, zirconium and base alloys of said metals, a surface coating of metal oxide particles of maximum dimension substantially less than the minimum dimension of said metal particles and selected from the group consisting of the oxides of calcium, magnesium, beryllium, thorium, gadolinium and mixtures thereof, and consolidating the so-coated particles into an integral mass by application of pressure and heat at sintering temperatures.
3. The process which comprises: thoroughly admixing finely divided particles of a metal of the group consisting of titanium, zirconium and base alloys of said metals with particles of an oxide of a metal selected from the group consisting of calcium, magnesium, beryllium, thorium, gadolinium and mixtures thereof more finely divided than said metal particles, whereby said metal particles are individually coated with said metal oxide, separating said coated metal particles from non-adhering metal oxide, and thereupon consolidating the so-coated particles by application of pressure and heat at sintering temperatures.
4. The process which comprises: thoroughly admixing particles of a metal of the group consisting of titanium, zirconium and base alloys of each having a mean dimension of the order of 1-2 microns with particles of an oxide of a metal selected from the group consisting of calcium, magnesium, beryllium, thorium, gadolinium and mixtures thereof, said metal oxide particles having a maximum dimension less than about one-tenth that of said metal particles, whereby said metal particles are individually coated with said metal oxide particles, separating the coated particles from non-adhering metal oxide particles and thereupon applying pressure at sintering temperatures, whereby said so-coated particles are consolidated.
5. The process which comprises: thoroughly admixing finely divided particles of a metal of the group consisting of titanium, zirconium and base alloys of said metals with particles of an oxide of a metal selected from the group consisting of calcium, magnesium, beryllium, thorium,
gadolinium and mixtures thereof more finely divided than said metal particles, whereby said metal particles are individually coated with said metal oxide, separating said coated metal particles from non-adhering metal oxide, and thereupon consolidating the so-coated particles by application of pressure and heat at sintering temperatures in an atmosphere which is inert with respect to said metal.
6. A process for the production of a sintered compact which comprises: thoroughly admixing particles of a metal selected from the group consisting of titanium, zirconium and base alloys of each having a mean dimension not greater than about two microns with particles of a metal oxide characterized by substantial insolubility in said metal and thermal stability in the presence of said metal at the sintering temperature, said oxide particles having a mean maximum dimension substantially smaller than that of said metal particles, whereby said metal particles are individually coated with said oxide, and thereupon consolidating the so-coated particles by application of pressure and heat at the sintering temperature in an atmosphere which is inert with respect to said metal.
7. A process for the production of a sintered compact which comprises: thoroughly admixing particles of a metal selected from the group consisting of titanium, zirconium and base alloys of each having a mean dimension not greater than about two microns with particles of a metal oxide characterized by substantial insolubility in said metal and thermal stability in the presence of said References Cited in the file of this patent UNITED STATES PATENTS 2,431,660 Gaudenzi Nov. 25, 1947

Claims (1)

1. THE PROCESS WHICH COMPRISES: APPLYING TO FINELY DIVIDED PARTICLES OF A METAL SELECTED FROM THE GROUP CONSISTING OF TITANIUM, ZIRCONIUM AND BASE ALLOYS OF SAID METALS, A SURFACE COATING OF A METAL OXIDE WHICH IS STABLE IN CONTACT WITH AND SUBSTANTIALLY INSOLUBLE IN SAID METAL AT SINTERING TEMPERATURES, AND CONSOLIDATING THE SO-COATED PARTICLES INTO AN INTEGRAL MASS WITH THE APPLICATION OF PRESSURE AND HEAT AT SINTERING TEMPERATURES.
US204055A 1957-01-15 1962-06-21 Powder metallurgy processes and products Expired - Lifetime US3181947A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US204055A US3181947A (en) 1957-01-15 1962-06-21 Powder metallurgy processes and products

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US634156A US3066391A (en) 1957-01-15 1957-01-15 Powder metallurgy processes and products
US204055A US3181947A (en) 1957-01-15 1962-06-21 Powder metallurgy processes and products

Publications (1)

Publication Number Publication Date
US3181947A true US3181947A (en) 1965-05-04

Family

ID=26899133

Family Applications (1)

Application Number Title Priority Date Filing Date
US204055A Expired - Lifetime US3181947A (en) 1957-01-15 1962-06-21 Powder metallurgy processes and products

Country Status (1)

Country Link
US (1) US3181947A (en)

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3387966A (en) * 1964-08-13 1968-06-11 Beryllium Corp Dry process for controlled surface oxidation of beryllium powders
US3398923A (en) * 1964-11-20 1968-08-27 Schwarzkopf Dev Company Shaped bodies with high temperature strength and corrosion resistance against moltenmetals particularly molten iron and steels
US3414046A (en) * 1964-12-10 1968-12-03 Schwarzkopf Dev Company Mold structures for continuously casting an elongated metal body of desired cross-section
US3453104A (en) * 1967-11-28 1969-07-01 Lockheed Aircraft Corp Process for making porous materials
US3853582A (en) * 1970-02-02 1974-12-10 Raytheon Co Metallized isotropic boron nitride body and method for making same
EP0167460A1 (en) * 1984-07-06 1986-01-08 Office National d'Etudes et de Recherches Aérospatiales (O.N.E.R.A.) Process for manufacturing titane-based alloys with small granular dimensions by means of powder metallurgy
US4612160A (en) * 1984-04-02 1986-09-16 Dynamet, Inc. Porous metal coating process and mold therefor
US20080277092A1 (en) * 2005-04-19 2008-11-13 Layman Frederick P Water cooling system and heat transfer system
US8652992B2 (en) 2009-12-15 2014-02-18 SDCmaterials, Inc. Pinning and affixing nano-active material
US8668803B1 (en) 2009-12-15 2014-03-11 SDCmaterials, Inc. Sandwich of impact resistant material
US8669202B2 (en) 2011-02-23 2014-03-11 SDCmaterials, Inc. Wet chemical and plasma methods of forming stable PtPd catalysts
US8679433B2 (en) 2011-08-19 2014-03-25 SDCmaterials, Inc. Coated substrates for use in catalysis and catalytic converters and methods of coating substrates with washcoat compositions
US8759248B2 (en) 2007-10-15 2014-06-24 SDCmaterials, Inc. Method and system for forming plug and play metal catalysts
US8803025B2 (en) 2009-12-15 2014-08-12 SDCmaterials, Inc. Non-plugging D.C. plasma gun
US8865611B2 (en) 2009-12-15 2014-10-21 SDCmaterials, Inc. Method of forming a catalyst with inhibited mobility of nano-active material
US9126191B2 (en) 2009-12-15 2015-09-08 SDCmaterials, Inc. Advanced catalysts for automotive applications
US9149797B2 (en) 2009-12-15 2015-10-06 SDCmaterials, Inc. Catalyst production method and system
US9156025B2 (en) 2012-11-21 2015-10-13 SDCmaterials, Inc. Three-way catalytic converter using nanoparticles
US9427732B2 (en) 2013-10-22 2016-08-30 SDCmaterials, Inc. Catalyst design for heavy-duty diesel combustion engines
US9511352B2 (en) 2012-11-21 2016-12-06 SDCmaterials, Inc. Three-way catalytic converter using nanoparticles
US9517448B2 (en) 2013-10-22 2016-12-13 SDCmaterials, Inc. Compositions of lean NOx trap (LNT) systems and methods of making and using same
US9586179B2 (en) 2013-07-25 2017-03-07 SDCmaterials, Inc. Washcoats and coated substrates for catalytic converters and methods of making and using same
US9687811B2 (en) 2014-03-21 2017-06-27 SDCmaterials, Inc. Compositions for passive NOx adsorption (PNA) systems and methods of making and using same

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2431660A (en) * 1944-12-01 1947-11-25 Bbc Brown Boveri & Cie Turbine blade

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2431660A (en) * 1944-12-01 1947-11-25 Bbc Brown Boveri & Cie Turbine blade

Cited By (60)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3387966A (en) * 1964-08-13 1968-06-11 Beryllium Corp Dry process for controlled surface oxidation of beryllium powders
US3398923A (en) * 1964-11-20 1968-08-27 Schwarzkopf Dev Company Shaped bodies with high temperature strength and corrosion resistance against moltenmetals particularly molten iron and steels
US3414046A (en) * 1964-12-10 1968-12-03 Schwarzkopf Dev Company Mold structures for continuously casting an elongated metal body of desired cross-section
US3453104A (en) * 1967-11-28 1969-07-01 Lockheed Aircraft Corp Process for making porous materials
US3853582A (en) * 1970-02-02 1974-12-10 Raytheon Co Metallized isotropic boron nitride body and method for making same
US4612160A (en) * 1984-04-02 1986-09-16 Dynamet, Inc. Porous metal coating process and mold therefor
EP0167460A1 (en) * 1984-07-06 1986-01-08 Office National d'Etudes et de Recherches Aérospatiales (O.N.E.R.A.) Process for manufacturing titane-based alloys with small granular dimensions by means of powder metallurgy
FR2567153A1 (en) * 1984-07-06 1986-01-10 Onera (Off Nat Aerospatiale) PROCESS FOR PREPARING, BY METALLURGY OF POWDERS, TITANIUM ALLOY WITH LOW GRAIN SIZE
US4601874A (en) * 1984-07-06 1986-07-22 Office National D'etudes Et De Recherche Aerospatiales (Onera) Process for forming a titanium base alloy with small grain size by powder metallurgy
US9599405B2 (en) 2005-04-19 2017-03-21 SDCmaterials, Inc. Highly turbulent quench chamber
US9216398B2 (en) 2005-04-19 2015-12-22 SDCmaterials, Inc. Method and apparatus for making uniform and ultrasmall nanoparticles
US9719727B2 (en) 2005-04-19 2017-08-01 SDCmaterials, Inc. Fluid recirculation system for use in vapor phase particle production system
US9023754B2 (en) 2005-04-19 2015-05-05 SDCmaterials, Inc. Nano-skeletal catalyst
US20080277092A1 (en) * 2005-04-19 2008-11-13 Layman Frederick P Water cooling system and heat transfer system
US9132404B2 (en) 2005-04-19 2015-09-15 SDCmaterials, Inc. Gas delivery system with constant overpressure relative to ambient to system with varying vacuum suction
US9180423B2 (en) 2005-04-19 2015-11-10 SDCmaterials, Inc. Highly turbulent quench chamber
US8906316B2 (en) 2007-05-11 2014-12-09 SDCmaterials, Inc. Fluid recirculation system for use in vapor phase particle production system
US8893651B1 (en) 2007-05-11 2014-11-25 SDCmaterials, Inc. Plasma-arc vaporization chamber with wide bore
US9592492B2 (en) 2007-10-15 2017-03-14 SDCmaterials, Inc. Method and system for forming plug and play oxide catalysts
US9186663B2 (en) 2007-10-15 2015-11-17 SDCmaterials, Inc. Method and system for forming plug and play metal compound catalysts
US9302260B2 (en) 2007-10-15 2016-04-05 SDCmaterials, Inc. Method and system for forming plug and play metal catalysts
US9737878B2 (en) 2007-10-15 2017-08-22 SDCmaterials, Inc. Method and system for forming plug and play metal catalysts
US8759248B2 (en) 2007-10-15 2014-06-24 SDCmaterials, Inc. Method and system for forming plug and play metal catalysts
US9089840B2 (en) 2007-10-15 2015-07-28 SDCmaterials, Inc. Method and system for forming plug and play oxide catalysts
US9597662B2 (en) 2007-10-15 2017-03-21 SDCmaterials, Inc. Method and system for forming plug and play metal compound catalysts
US8803025B2 (en) 2009-12-15 2014-08-12 SDCmaterials, Inc. Non-plugging D.C. plasma gun
US9522388B2 (en) 2009-12-15 2016-12-20 SDCmaterials, Inc. Pinning and affixing nano-active material
US8992820B1 (en) 2009-12-15 2015-03-31 SDCmaterials, Inc. Fracture toughness of ceramics
US8932514B1 (en) 2009-12-15 2015-01-13 SDCmaterials, Inc. Fracture toughness of glass
US8906498B1 (en) 2009-12-15 2014-12-09 SDCmaterials, Inc. Sandwich of impact resistant material
US9126191B2 (en) 2009-12-15 2015-09-08 SDCmaterials, Inc. Advanced catalysts for automotive applications
US8877357B1 (en) 2009-12-15 2014-11-04 SDCmaterials, Inc. Impact resistant material
US9149797B2 (en) 2009-12-15 2015-10-06 SDCmaterials, Inc. Catalyst production method and system
US8652992B2 (en) 2009-12-15 2014-02-18 SDCmaterials, Inc. Pinning and affixing nano-active material
US8865611B2 (en) 2009-12-15 2014-10-21 SDCmaterials, Inc. Method of forming a catalyst with inhibited mobility of nano-active material
US8859035B1 (en) 2009-12-15 2014-10-14 SDCmaterials, Inc. Powder treatment for enhanced flowability
US8828328B1 (en) 2009-12-15 2014-09-09 SDCmaterails, Inc. Methods and apparatuses for nano-materials powder treatment and preservation
US8668803B1 (en) 2009-12-15 2014-03-11 SDCmaterials, Inc. Sandwich of impact resistant material
US8821786B1 (en) * 2009-12-15 2014-09-02 SDCmaterials, Inc. Method of forming oxide dispersion strengthened alloys
US9308524B2 (en) 2009-12-15 2016-04-12 SDCmaterials, Inc. Advanced catalysts for automotive applications
US9332636B2 (en) 2009-12-15 2016-05-03 SDCmaterials, Inc. Sandwich of impact resistant material
US9533289B2 (en) 2009-12-15 2017-01-03 SDCmaterials, Inc. Advanced catalysts for automotive applications
US9433938B2 (en) 2011-02-23 2016-09-06 SDCmaterials, Inc. Wet chemical and plasma methods of forming stable PTPD catalysts
US9216406B2 (en) * 2011-02-23 2015-12-22 SDCmaterials, Inc. Wet chemical and plasma methods of forming stable PtPd catalysts
US8669202B2 (en) 2011-02-23 2014-03-11 SDCmaterials, Inc. Wet chemical and plasma methods of forming stable PtPd catalysts
US20140249021A1 (en) * 2011-02-23 2014-09-04 SDCmaterials, Inc. Wet chemical and plasma methods of forming stable ptpd catalysts
US9498751B2 (en) 2011-08-19 2016-11-22 SDCmaterials, Inc. Coated substrates for use in catalysis and catalytic converters and methods of coating substrates with washcoat compositions
US8969237B2 (en) 2011-08-19 2015-03-03 SDCmaterials, Inc. Coated substrates for use in catalysis and catalytic converters and methods of coating substrates with washcoat compositions
US8679433B2 (en) 2011-08-19 2014-03-25 SDCmaterials, Inc. Coated substrates for use in catalysis and catalytic converters and methods of coating substrates with washcoat compositions
US9533299B2 (en) 2012-11-21 2017-01-03 SDCmaterials, Inc. Three-way catalytic converter using nanoparticles
US9156025B2 (en) 2012-11-21 2015-10-13 SDCmaterials, Inc. Three-way catalytic converter using nanoparticles
US9511352B2 (en) 2012-11-21 2016-12-06 SDCmaterials, Inc. Three-way catalytic converter using nanoparticles
US9586179B2 (en) 2013-07-25 2017-03-07 SDCmaterials, Inc. Washcoats and coated substrates for catalytic converters and methods of making and using same
US9517448B2 (en) 2013-10-22 2016-12-13 SDCmaterials, Inc. Compositions of lean NOx trap (LNT) systems and methods of making and using same
US9566568B2 (en) 2013-10-22 2017-02-14 SDCmaterials, Inc. Catalyst design for heavy-duty diesel combustion engines
US9427732B2 (en) 2013-10-22 2016-08-30 SDCmaterials, Inc. Catalyst design for heavy-duty diesel combustion engines
US9950316B2 (en) 2013-10-22 2018-04-24 Umicore Ag & Co. Kg Catalyst design for heavy-duty diesel combustion engines
US9687811B2 (en) 2014-03-21 2017-06-27 SDCmaterials, Inc. Compositions for passive NOx adsorption (PNA) systems and methods of making and using same
US10086356B2 (en) 2014-03-21 2018-10-02 Umicore Ag & Co. Kg Compositions for passive NOx adsorption (PNA) systems and methods of making and using same
US10413880B2 (en) 2014-03-21 2019-09-17 Umicore Ag & Co. Kg Compositions for passive NOx adsorption (PNA) systems and methods of making and using same

Similar Documents

Publication Publication Date Title
US3066391A (en) Powder metallurgy processes and products
US3181947A (en) Powder metallurgy processes and products
US2893102A (en) Article fabrication from powders
US3660049A (en) Dispersion strengthened electrical heating alloys by powder metallurgy
US2809891A (en) Method of making articles from aluminous metal powder
US4681629A (en) Powder metallurgical process for manufacturing copper-nickel-tin spinodal alloy articles
US3639179A (en) Method of making large grain-sized superalloys
Rabin et al. Microstructure and tensile properties of Fe 3 Al produced by combustion synthesis/hot isostatic pressing
US3158473A (en) Method for producing composite bodies
GB2083500A (en) Dispersion-strengthened copper alloys
US2884688A (en) Sintered ni-al-zr compositions
US3323880A (en) Beryllium-aluminum-magnesium composite
US3366479A (en) Powder metallurgy
US3205099A (en) Stable dispersoid composites and production thereof
US2765227A (en) Titanium carbide composite material
US3533760A (en) Dispersion strengthened nickel-chromium alloy composition
Kislyi et al. Regularities of sintering of zirconium diboride-molybenum alloys
US2840891A (en) High temperature structural material and method of producing same
US5350107A (en) Iron aluminide alloy coatings and joints, and methods of forming
US3196007A (en) Beryllium copper composition and method of producing green compacts and sintered articles therefrom
US5261941A (en) High strength and density tungsten-uranium alloys
US3166416A (en) Process for producing dispersionhardened alloys
US3150975A (en) Method of making intermetallic compound-composition bodies
US3472709A (en) Method of producing refractory composites containing tantalum carbide,hafnium carbide,and hafnium boride
US3010824A (en) Method of manufacture of an aluminum alloy, and the alloy obtained by this process