EP0305766A2 - Discontinuous fiber and particulate reinforced refractory metal composite - Google Patents

Discontinuous fiber and particulate reinforced refractory metal composite Download PDF

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Publication number
EP0305766A2
EP0305766A2 EP88112814A EP88112814A EP0305766A2 EP 0305766 A2 EP0305766 A2 EP 0305766A2 EP 88112814 A EP88112814 A EP 88112814A EP 88112814 A EP88112814 A EP 88112814A EP 0305766 A2 EP0305766 A2 EP 0305766A2
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EP
European Patent Office
Prior art keywords
composition
dispersoid
niobium
metal
atmospheres
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.)
Withdrawn
Application number
EP88112814A
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German (de)
French (fr)
Other versions
EP0305766A3 (en
Inventor
Robert Leroy Ammon
Raymond William Buckman
Ram Bajaj
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.)
CBS Corp
Original Assignee
Westinghouse Electric Corp
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
Application filed by Westinghouse Electric Corp filed Critical Westinghouse Electric Corp
Publication of EP0305766A2 publication Critical patent/EP0305766A2/en
Publication of EP0305766A3 publication Critical patent/EP0305766A3/en
Withdrawn legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C27/00—Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
    • C22C27/02—Alloys based on vanadium, niobium, or tantalum
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C49/00—Alloys containing metallic or non-metallic fibres or filaments
    • C22C49/02—Alloys containing metallic or non-metallic fibres or filaments characterised by the matrix material
    • C22C49/10—Refractory metals
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/10—Alloys containing non-metals
    • C22C1/1084—Alloys containing non-metals by mechanical alloying (blending, milling)
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C47/00—Making alloys containing metallic or non-metallic fibres or filaments
    • C22C47/14—Making alloys containing metallic or non-metallic fibres or filaments by powder metallurgy, i.e. by processing mixtures of metal powder and fibres or filaments

Definitions

  • the invention relates to niobium-based refractory metal composites that are reinforced with either particu­lates or discontinuous fibers.
  • Materials used in nuclear power systems in outer space must be able to withstand elevated temperatures in excess of 1600K for long periods of time, radiation, liquid metal coolants, high fluence neutron irradiations, a vacuum, and high stresses.
  • the materials should be lightweight, strong, ductile, and capable of being fabricated into various shapes. Very few materials can meet these stringent requirements.
  • the main object of the invention is to make a composite material that has these properties.
  • niobium-based alloys containing dispersions of particulates or fibers have excellent properties which make them very suitable for use in nuclear power systems in outer space. These composites have a high melting point, a low density, excellent ductil­ity, irradiation swelling resistance, coolant compatibili­ty, high elevated temperature strength, stability, and a high modulus. We have further found that the properties of these composites, where particulates are used, can be enhanced through the use of mechanical alloying in their fabrication.
  • the matrix material for both fiber and particu­late reinforced composite is niobium. While niobium itself can be used, it is preferable to use alloys of niobium as they are stronger.
  • An alloy may contain any amount of the alloying metal, but it is preferable to use an alloy that contains about 50 to about 90% by weight niobium and about 10 to about 50% by weight of the alloying metal.
  • Preferred alloying metals are tungsten, hafnium, zirconium, and mixtures thereof, as these alloying metals form the strong­est alloys with niobium. Additional alloying elements such as carbon, oxygen, and nitrogen may be added.
  • the matrix material is used in the form of a powder which can be of almost any particle size.
  • the dispersoid can be an oxide, carbide, or boride of titanium, hafnium, zirconium, silicon, or a mixture thereof.
  • Partic­ulate dispersoids are preferably about 1 to about 250 microns in particle size.
  • the dispersoid and the matrix material are mixed together.
  • About 20 to about 80% by volume of the matrix material is mixed with about 80 to about 20% by volume of the dispersoid.
  • the next step of the process of this invention is the mechanical alloying of the composition.
  • Mechanical alloying is accomplished by placing the composition in an attritor, which is a high-speed ball mill operated under vacuum or in an inert atmosphere.
  • the balls used in the attritor can be made of an inert material or they can be made of the same material which comprises the matrix material.
  • the attritor is typically operated at room temperature or slightly above room temperature for the time, which may vary from hours to several days, necessary to disperse the dispersoid in the matrix material and produce a flake-like composite particulate.
  • the composition is cold pressed.
  • Cold pressing reduces the volume of the composition and forms a low density green compact of 50 to 70% of theoretical density so that a vacuum can be easily applied in the next step of the process without drawing particles into the vacuum system.
  • cold pressing is an optional step, it is preferably performed as it facilitates handling in the next step.
  • Cold pressing is preferably performed at room temperature, although higher or lower temperatures could also be used. Sufficient pressure should be used to increase the density to greater than 60% of theoretical density. Normally, a pressure in excess of 340 atmospheres will be required.
  • Cold pressing is preferably performed isostatically so that the resulting shape has a uniform density throughout.
  • the green compact is consolidated, preferably by hot isostatic pressing, to a density greater than 90% of theoretical density; consolidation can also be accomplished by sintering or hot pressing.
  • the cold pressed shape is enclosed in a can which is then evacuated to a pressure of less than 1 x 10 ⁇ 4 torr. While the temperature of consolidation will depend on the composition of the partic­ular composite, temperatures in excess of 1000°C and pressures in excess of 680 atmospheres will normally be required.
  • the densified compact can be extruded through a die to form a required shape.
  • short fibers of a high strength material are used to strengthen the composite.
  • the fibers preferably about 1 to about 600 microns in diameter, can be carbides, borides, oxides, or nitrides of such elements as titanium, hafnium, zirconium, silicon, or mixtures thereof.
  • the fibers preferably have a length to diameter ratio of at least 5.
  • the surface of the fiber is modified
  • Surface modification is optional, but it is preferable to surface modify the fiber in order to help prevent the formation of intermetallic compounds at the interface of fiber and the matrix metal.
  • methods of surface modification include coating the fiber or ion implanting the fiber surface.
  • the fiber can be coated, for example, with silicon carbide or silicides of niobium or molybdenum or niobium diboride. This can be accomplished by evapora­tion with an electron beam, reactive evaporation or glow discharge method.
  • the fibers can also be ion implanted using ions of, for example, helium, argon, or nitrogen to render a thin surface layer of the fiber amorphous.
  • the fibers and powdered matrix material are processed together.
  • About 50 to about 90% by volume of the matrix material is mixed with about 50 to about 10% by volume of the fibers.
  • the mixture is preferably cold pressed to reduce the volume of the composite and form a green compact shape so that a vacuum can be used in the next step of the process, with ease, and without drawing the powders into the vacuum system.
  • cold pressing is an optional step, it is preferably performed as it simplifies process­ing at room temperature, although higher or lower tempera­tures could also be used.
  • Sufficient pressure should be used to increase the density to greater than 50% of the theoretical density. Normally, a pressure in excess of 340 atmospheres will be required.
  • Cold pressing is preferably performed isostatically so that the resulting shape has a homogeneous density.
  • the green compact shape is consolidated to full density by one of the several processes.
  • hot isostatic pressing can be used for this purpose. While the temperature required for hot isostatic pressing will depend on the particular composite being processed, temperatures in excess of 1000°C and pressures in excess of 680 atmo­spheres will normally be required.
  • the consolidated compact is extruded through a die to form a shape having a longitudinally aligned micro-­structure. The shape can then be cut and machined as required. Options other than hot isostatic pressing such as hot pressing and sintering may also be employed follow­ing the cold pressing stage.
  • 250 gm of ZrC, having a particle size of 5 microns, is mixed with 1200 gm of powdered alloy of 80% niobium, 20% tungsten.
  • the mixture is placed in an attritor and is mechanically alloyed for 24 hours at room temperature to produce a flake-like particulate.
  • the particulate is cold pressed at greater than 340 atmospheres at room temperature.
  • the resulting rod-shaped slug is then hot isostatically pressed at a temperature of 1000°C for 4 hours at greater than 680 atmospheres, and is then extruded through a die to form a shape.
  • 250 gm of ZrC fibers having a length of 500 microns and 25 micron diameter is surface modified with an ion beam of about 1015-1016 ions/cm2. Then 250 gm of fibers (density about 6.7 g/cm3) are mixed with about 1200 gm of powdered alloy of 80% niobium and 20% tungsten (density ⁇ 10.7 g/cm3). The mixture is cold pressed at greater than 340 atmospheres at room temperature to produce a rod-shaped green compact. The compact is hot pressed under argon or helium at 1200°C and 1700 atmospheres for 1 hour. It is then extruded through a die to form cylinder, rod, or tube as desired.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Powder Metallurgy (AREA)

Abstract

A method of making a reinforced refractory metal composite. A composition is prepared which comprises about 50 to about 99.9% by volume of niobium and about 0.1 to about 50% by volume of a particulate or fibrous dispersoid. The particulate dispersoid is an oxide, carbide, or boride of titanium, hafnium, zirconium, silicon, or a mixture thereof. The fibrous dispersoid is a carbide or boride of titanium, hafnium, zirconium, silicon, or a mixture there­of. The composition is mechanically alloyed in vacuum or in an inert atmosphere if a particulate dispersed is used It is then hot pressed at a temperature greater than at 1000°C and a pressure greater than 70 atmospheres, and is extruded to form a shape. A fiber reinforced refractory metal composite made by this method is also described.

Description

  • The invention relates to niobium-based refractory metal composites that are reinforced with either particu­lates or discontinuous fibers.
  • Materials used in nuclear power systems in outer space must be able to withstand elevated temperatures in excess of 1600K for long periods of time, radiation, liquid metal coolants, high fluence neutron irradiations, a vacuum, and high stresses. In addition, the materials should be lightweight, strong, ductile, and capable of being fabricated into various shapes. Very few materials can meet these stringent requirements.
  • The main object of the invention is to make a composite material that has these properties.
  • We have discovered that niobium-based alloys containing dispersions of particulates or fibers have excellent properties which make them very suitable for use in nuclear power systems in outer space. These composites have a high melting point, a low density, excellent ductil­ity, irradiation swelling resistance, coolant compatibili­ty, high elevated temperature strength, stability, and a high modulus. We have further found that the properties of these composites, where particulates are used, can be enhanced through the use of mechanical alloying in their fabrication. Additional enhancement is also attained by surface modification of fibers, where fibers are used, to prevent the formation of intermetallic compounds at the interface of the niobium matrix and the fibers; these intermetallic compounds tend to embrittle the composite and can lead to the formation of cracks
  • The matrix material for both fiber and particu­late reinforced composite is niobium. While niobium itself can be used, it is preferable to use alloys of niobium as they are stronger. An alloy may contain any amount of the alloying metal, but it is preferable to use an alloy that contains about 50 to about 90% by weight niobium and about 10 to about 50% by weight of the alloying metal. Preferred alloying metals are tungsten, hafnium, zirconium, and mixtures thereof, as these alloying metals form the strong­est alloys with niobium. Additional alloying elements such as carbon, oxygen, and nitrogen may be added. The matrix material is used in the form of a powder which can be of almost any particle size.
  • In the particulate reinforced composite, the dispersoid can be an oxide, carbide, or boride of titanium, hafnium, zirconium, silicon, or a mixture thereof. Partic­ulate dispersoids are preferably about 1 to about 250 microns in particle size.
  • In the first step of the process of this inven­tion for preparing the refractory metal composite using a particulate dispersoid, the dispersoid and the matrix material are mixed together. About 20 to about 80% by volume of the matrix material is mixed with about 80 to about 20% by volume of the dispersoid.
  • The next step of the process of this invention is the mechanical alloying of the composition. Mechanical alloying is accomplished by placing the composition in an attritor, which is a high-speed ball mill operated under vacuum or in an inert atmosphere. The balls used in the attritor can be made of an inert material or they can be made of the same material which comprises the matrix material. The attritor is typically operated at room temperature or slightly above room temperature for the time, which may vary from hours to several days, necessary to disperse the dispersoid in the matrix material and produce a flake-like composite particulate.
  • In the next step of the process of this inven­tion, the composition is cold pressed. Cold pressing reduces the volume of the composition and forms a low density green compact of 50 to 70% of theoretical density so that a vacuum can be easily applied in the next step of the process without drawing particles into the vacuum system. While cold pressing is an optional step, it is preferably performed as it facilitates handling in the next step. Cold pressing is preferably performed at room temperature, although higher or lower temperatures could also be used. Sufficient pressure should be used to increase the density to greater than 60% of theoretical density. Normally, a pressure in excess of 340 atmospheres will be required. Cold pressing is preferably performed isostatically so that the resulting shape has a uniform density throughout.
  • In the next step of the process of this inven­tion, the green compact is consolidated, preferably by hot isostatic pressing, to a density greater than 90% of theoretical density; consolidation can also be accomplished by sintering or hot pressing. The cold pressed shape is enclosed in a can which is then evacuated to a pressure of less than 1 x 10⁻⁴ torr. While the temperature of consolidation will depend on the composition of the partic­ular composite, temperatures in excess of 1000°C and pressures in excess of 680 atmospheres will normally be required. After consolidation, the densified compact can be extruded through a die to form a required shape.
  • In the fiber-reinforced composite, short fibers of a high strength material are used to strengthen the composite. The fibers, preferably about 1 to about 600 microns in diameter, can be carbides, borides, oxides, or nitrides of such elements as titanium, hafnium, zirconium, silicon, or mixtures thereof. The fibers preferably have a length to diameter ratio of at least 5.
  • In the first step of the process of this inven­tion using fibers, the surface of the fiber is modified Surface modification is optional, but it is preferable to surface modify the fiber in order to help prevent the formation of intermetallic compounds at the interface of fiber and the matrix metal. Examples of methods of surface modification include coating the fiber or ion implanting the fiber surface. The fiber can be coated, for example, with silicon carbide or silicides of niobium or molybdenum or niobium diboride. This can be accomplished by evapora­tion with an electron beam, reactive evaporation or glow discharge method. The fibers can also be ion implanted using ions of, for example, helium, argon, or nitrogen to render a thin surface layer of the fiber amorphous.
  • In the next step of the process of this inven­tion, the fibers and powdered matrix material are processed together. About 50 to about 90% by volume of the matrix material is mixed with about 50 to about 10% by volume of the fibers.
  • The mixture is preferably cold pressed to reduce the volume of the composite and form a green compact shape so that a vacuum can be used in the next step of the process, with ease, and without drawing the powders into the vacuum system. While cold pressing is an optional step, it is preferably performed as it simplifies process­ing at room temperature, although higher or lower tempera­tures could also be used. Sufficient pressure should be used to increase the density to greater than 50% of the theoretical density. Normally, a pressure in excess of 340 atmospheres will be required. Cold pressing is preferably performed isostatically so that the resulting shape has a homogeneous density.
  • In the next step of the process of this inven­tion, the green compact shape is consolidated to full density by one of the several processes. For example, hot isostatic pressing can be used for this purpose. While the temperature required for hot isostatic pressing will depend on the particular composite being processed, temperatures in excess of 1000°C and pressures in excess of 680 atmo­spheres will normally be required. After hot isostatic pressing, the consolidated compact is extruded through a die to form a shape having a longitudinally aligned micro-­structure. The shape can then be cut and machined as required. Options other than hot isostatic pressing such as hot pressing and sintering may also be employed follow­ing the cold pressing stage.
  • The following examples further illustrate this invention.
  • 250 gm of ZrC, having a particle size of 5 microns, is mixed with 1200 gm of powdered alloy of 80% niobium, 20% tungsten. The mixture is placed in an attritor and is mechanically alloyed for 24 hours at room temperature to produce a flake-like particulate. The particulate is cold pressed at greater than 340 atmospheres at room temperature. The resulting rod-shaped slug is then hot isostatically pressed at a temperature of 1000°C for 4 hours at greater than 680 atmospheres, and is then extruded through a die to form a shape.
  • 250 gm of ZrC fibers having a length of 500 microns and 25 micron diameter is surface modified with an ion beam of about 10¹⁵-10¹⁶ ions/cm². Then 250 gm of fibers (density about 6.7 g/cm³) are mixed with about 1200 gm of powdered alloy of 80% niobium and 20% tungsten (density ∼10.7 g/cm³). The mixture is cold pressed at greater than 340 atmospheres at room temperature to produce a rod-shaped green compact. The compact is hot pressed under argon or helium at 1200°C and 1700 atmospheres for 1 hour. It is then extruded through a die to form cylinder, rod, or tube as desired.

Claims (22)

1. A method of making a reinforced refractory metal composite characterized by the steps of:
(A) preparing a composition which comprises:
(i) about 50 to about 90% by volume of a metal which comprises niobium; and
(ii) about 10% to about 50% by volume of a discontinuous fiber dispersoid selected from a group consisting of carbides, oxides, borides, nitrides, and mixtures thereof, of titanium, hafnium, zirconi­um, silicon, and mixtures thereof;
(B) consolidating said composition at a tempera­ture greater than 1000°C and a pressure greater than 340 atmospheres; and
(C) extruding said composition into a shape.
2. A method according to Claim 1 characterized in that said metal is an alloy of niobium containing about 50 to about 99.5% by weight niobium.
3. A method according to Claim 1 characterized by the additional step of surface modifying said fibrous dispersoid before it is consolidated.
4. A method according to Claim 1 characterized by the additional step of cold pressing said composition to form a shape prior to said consolidating.
5. A method according to Claim 4 characterized in that said cold pressing is isostatic cold pressing at room temperature and a pressure greater than 340 atmospheres.
6. A method according to Claim 1 characterized in that said consolidating is by hot pressing.
7. A method according to Claim 6 characterized in that said hot pressing is hot isostatic pressing.
8. A method according to Claim 1 characterized in that said consolidating is by sintering.
9. A method according to Claim 1 characterized by the additional last steps of cutting and machining said extruded shape.
10. A method according to Claim 1 characterized in that said fibrous dispersoid has a diameter of about 1 to about 600 microns.
11. A composition characterized in that it includes:
(A) about 50 to about 90.5% by volume of a metal which comprises niobium; and
(B) about 10 to about 50% by volume of a fibrous dispersoid selected from the group consisting of titanium carbide, titanium boride, hafnium carbide, hafnium boride, zirconium carbide, zirconium boride, silicon carbide, silicon boride, and mixtures thereof.
12. A composition according to Claim 11 charac­terized in that said metal is an alloy of niobium.
13. A composition according to Claim 12 charac­terized in that said alloy is an alloy with a metal select­ed from the group consisting of tungsten, hafnium, zirconium, carbon, oxygen, nitrogen and mixtures thereof.
14. A composition according to Claim 11 charac­terized in that said fibrous dispersoid has a diameter of about 1 to about 600 microns.
15. A composition according to Claim 11 charac­terized in that said composition is hot pressed at a temperature greater than 1000°C and a pressure greater than 340 atmospheres and extruded.
16. A composite according to Claim 15 characterized in that said composition is cold pressed to form a shape at a pressure greater than 340 atmospheres prior to said hot pressing.
17. A composite according to Claim 15 charac­terized in that said fibrous dispersoid is surface modified.
18. A method of making a reinforced refractory metal composite characterized by the steps of:
(A) preparing a composition which comprises:
(i) about 50 to about 90% by volume of a metal which comprises niobium; and
(ii) about 10 to about 50% by volume of particulate dispersoid selected from the group consisting of oxides, car­bides, borides, and mixtures thereof, of titanium, hafnium, zirconium, silicon, and mixtures thereof;
(B) mechanically alloying said composition in vacuum or inert atmosphere;
(C) consolidating said composition at a tempera­ture greater than 1000°C and a pressure greater than 340 atmospheres; and
(D) extruding said composition into a shape.
19. A method according to Claim 18 characterized in that said metal is an alloy of niobium containing about 50 to about 99.5% by weight niobium.
20. A method according to Claim 18 characterized by the additional step of cold pressing said composition to form a shape after said mechanical alloying and prior to said consolidating.
21. A method according to Claim 20 characterized in that said cold pressing is isostatic cold pressing at room temperature and a pressure greater than about 340 atmospheres.
22. A method according to Claim 18 characterized in that said consolidating is by isostatic hot pressing.
EP88112814A 1987-09-03 1988-08-05 Discontinuous fiber and particulate reinforced refractory metal composite Withdrawn EP0305766A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US9296387A 1987-09-03 1987-09-03
US92963 1987-09-03

Publications (2)

Publication Number Publication Date
EP0305766A2 true EP0305766A2 (en) 1989-03-08
EP0305766A3 EP0305766A3 (en) 1990-04-04

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EP88112814A Withdrawn EP0305766A3 (en) 1987-09-03 1988-08-05 Discontinuous fiber and particulate reinforced refractory metal composite

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EP (1) EP0305766A3 (en)
JP (1) JPS6475636A (en)
KR (1) KR890005288A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014044433A1 (en) * 2012-09-24 2014-03-27 Siemens Aktiengesellschaft Production of a refractory metal component
CN107829005A (en) * 2017-11-08 2018-03-23 西北有色金属研究院 A kind of Nb Si C alloy bars and preparation method thereof
CN114807659A (en) * 2022-05-05 2022-07-29 湖南江滨机器（集团）有限责任公司 Aluminum-based composite material containing titanium diboride and niobium diboride, preparation method thereof and diesel engine piston

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111910136B (en) * 2020-06-23 2021-10-22 西安理工大学 Three-dimensional fiber skeleton toughened metal ceramic and preparation method thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3098723A (en) * 1960-01-18 1963-07-23 Rand Corp Novel structural composite material
US3738817A (en) * 1968-03-01 1973-06-12 Int Nickel Co Wrought dispersion strengthened metals by powder metallurgy
US4117565A (en) * 1976-08-31 1978-10-03 The Foundation: The Research Institute For Special Inorganic Materials Chromium base alloy composite materials reinforced with continuous silicon carbide fibers and a method for producing the same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3098723A (en) * 1960-01-18 1963-07-23 Rand Corp Novel structural composite material
US3738817A (en) * 1968-03-01 1973-06-12 Int Nickel Co Wrought dispersion strengthened metals by powder metallurgy
US4117565A (en) * 1976-08-31 1978-10-03 The Foundation: The Research Institute For Special Inorganic Materials Chromium base alloy composite materials reinforced with continuous silicon carbide fibers and a method for producing the same

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014044433A1 (en) * 2012-09-24 2014-03-27 Siemens Aktiengesellschaft Production of a refractory metal component
CN107829005A (en) * 2017-11-08 2018-03-23 西北有色金属研究院 A kind of Nb Si C alloy bars and preparation method thereof
CN107829005B (en) * 2017-11-08 2020-02-07 西北有色金属研究院 Nb-Si-C alloy bar and preparation method thereof
CN114807659A (en) * 2022-05-05 2022-07-29 湖南江滨机器（集团）有限责任公司 Aluminum-based composite material containing titanium diboride and niobium diboride, preparation method thereof and diesel engine piston
CN114807659B (en) * 2022-05-05 2023-04-18 湖南江滨机器（集团）有限责任公司 Aluminum-based composite material containing titanium diboride and niobium diboride, preparation method thereof and diesel engine piston

Also Published As

Publication number Publication date
KR890005288A (en) 1989-05-13
EP0305766A3 (en) 1990-04-04
JPS6475636A (en) 1989-03-22

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