US3638293A - High-density tungsten-rhenium-nickel alloys and articles - Google Patents

High-density tungsten-rhenium-nickel alloys and articles Download PDF

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US3638293A
US3638293A US857478A US3638293DA US3638293A US 3638293 A US3638293 A US 3638293A US 857478 A US857478 A US 857478A US 3638293D A US3638293D A US 3638293DA US 3638293 A US3638293 A US 3638293A
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percent
rhenium
density
nickel
tungsten
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Sven Torsten Lennart Peterson
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Auralight AB
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00—Contacts
    • H01H1/02—Contacts characterised by the material thereof
    • H01H1/021—Composite material
    • 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
    • C22C27/04—Alloys based on tungsten or molybdenum
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00—Contacts
    • H01H1/02—Contacts characterised by the material thereof
    • H01H2001/0208—Contacts characterised by the material thereof containing rhenium
    • 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

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  • the present invention provides high density tungsten-rhenium-nickel alloys and articles made therefrom.
  • Sintered high-density alloy compositions containing between about 1 and 7.5 percent rhenium and between about 0.15 and 0.3 percent nickel, and electric contacts prepared therefrom.
  • the preferred compositions have a density of at least 18.6 g./cc. and more preferably, a density of at least 19 g./cc.
  • preferred compositions include the following: Between 2 and 7 percent rhenium and between 0.2 and 0.3 percent nickel; between 1 and 7.5 percent rhenium and 0.3 percent nickel; between 2 and 5.5 percent rhenium and 0.2 and 0.3 percent nickel; and about 3 percent rhenium and 0.15 percent nickel.
  • compositions are also useful, although not as preferred as those listed in the preceding paragraph: Between 1 and 5.5 percent rhenium and 0.15 and 0.3 percent nickel; and between 2 and 4 percent rhenium and 0.15 percent nickel.
  • FIG, 1 is a graph relating alloy compositions to the density as sintered for the conditions and compositions in the examples herein;
  • FIG. 2 is a photomicrograph, 100 x, of an unetched section of the as sintered alloy composition containing 0.2 percent nickel, 3 percent rhenium and the remainder tungsten;
  • FIG. 3 is a photomicrograph, 425 x, of an etched section of the same alloy.
  • the tungsten alloy articles of the present invention are manufactured by conventional powder metallurgic techniques.
  • the alloy powder mixture may be prepared by admixing powders of nickel, rhenium and tungsten. They are preferably prepared by admixing reducible metal compounds of each of the metals.
  • Nickel is preferably added as nickel carbonate or nickel oxide.
  • Rhenium is preferably added as ammonium perrhenate.
  • Tungsten is preferably added as tungstic oxide.
  • Mixing is preferably carried out in a ball mill having a liquid medium, e.g., alcohol, methylene chloride, etc.
  • the mixture is removed from the ball mill, dried and reduced in hydrogen, preferably at a temperature of between about 700 and l,000 C.
  • the resultant mixed metal powders are preferably treated by addition of a hydrocarbon material such as paraffin wax in a solvent to improve compactability.
  • a green compact is then formed by pressing, preferably at a pressure of about 15 tons per square inch.
  • the green compact is then presintered, preferably at a temperature of about 800 to 1,000 C. for a period of about one-half hour. Sintering is then carried out at elevated temperatures.
  • the preferred sin tering temperature utilizing the alloy compositions of the present invention, is between about 1,400 and 1,550 C.
  • Sintering time is preferably between about 1 and 3 hours. This relatively low temperature sintering provides the desired density without at the same time reaching sufficiently high temperatures to undesirably affect physical and metallographic properties. Presintering and sintering are carried out in a protective atmosphere, i.e., vacuum, an inert atmosphere or a reducing atmosphere. The sintered articles may then be finished by tumbling or lapping, or, if necessary, finish machined to the desired dimensions.
  • a protective atmosphere i.e., vacuum, an inert atmosphere or a reducing atmosphere.
  • the tungsten alloy articles of all the examples were prepared using the same procedure.
  • a mixture of tungstic oxide, ammonium perrhenate, and nickel carbonate was thoroughly mixed in a ball mill containing ethyl alcohol.
  • the mixed powder was then reduced in hydrogen at a temperature of between about 700 and 1,000 C.
  • the mixed powders were then treated with a solution of paraffin wax in benzene in the conventional manner.
  • Green compacts were formed at 15 tons per square inch pressure.
  • the green compacts were then presintered at a temperature of between about 800 and l,000 C. for one-half hour in a hydrogen atmosphere (dewpoint 60 F.) and were then sintered in a hydrogen atmosphere (dewpoint 60 F.) at a temperature of 1,500" C. for 1 hour.
  • FIG. 2 a photomicrograph x) of an unetched section
  • FIG. 3 a photomicrograph (425 x) of an etched section of the alloy composition 0.20 percent nickel and 3 percent rhenium.
  • compositions of claim 1 containing about 0.3 percent nickel and having a density as sintered in excess of 19 g./cc.
  • compositions of claim 1 containing between about 1 and 5.5 percent rhenium.
  • compositions of claim 4 containing at least about 2 percent rhenium and containing at least about 0.2 percent nickel and having a density as sintered in excess of 19 g./cc.
  • compositions of claim 4 containing between about 2 and 4 percent rhenium and containing about 0.15 percent nickel.
  • compositions of claim 6 containing about 3 percent rhenium and having a density as sintered in excess of 19 g./cc.
  • Sintered high-density electric contacts consisting essentially of between about I and 7.5 percent rhenium, between about 0.15 and 0.3 percent nickel and the balance tungsten.
  • the electric contacts of claim 8 containing between about 2 and 7 percent rhenium and between about 0.2 and 0.3 percent nickel, and having a density in excess of IQ g./cc.
  • the electric contacts of claim 8 containing about 0.3 percent nickel and having a density in excess of l9 g./cc.
  • the electric contacts of claim 11 containing at least 2 percent rhenium and containing at least 0.2 percent nickel and having a density in excess of 19 g./cc.
  • the electric contacts of claim 13 containing about 3 percent rhenium and having a density in excess of 19 g./cc.

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

Abstract

Sintered alloys of tungsten containing between about 1 percent and 7.5 percent rhenium and between about 0.15 percent and 0.3 percent nickel and electrical articles, particularly contacts, prepared from said alloys. The invention also includes a method of improving the density of tungsten alloys.

Description

United States Patent [151 3,638,293 Peterson [4 Feb. 1, 1972 [54] HIGH-DENSITY TUNGSTEN-RHENIUM- 2,227,445 l/l94l Driggs.... ..75/200 NICKEL ALLOYS AND ARTICLES 2,466,992 4/1949 Kurtz ..75/ 176 3,359,082 12/1967 Dickinson ..29/182 [72] Inventor: Sven Torsten Lennart Peterson, Vendelso,
Sweden [73] Assignee: Lumalampan Aktiebolag, Stockholm,
Sweden [22] Filed: Sept. 12, 1969 I 211 App]. No: 857,478
[52] US. Cl ..29/l82, 75/176, 75/221, 252/515 [51] Int. Cl. ..B22i 3/00 [58] Field of Search ..29/182; 75/176; 252/515 [56] References Cited UNITED STATES PATENTS 2,157,935 5/1939 Hensel ..75/l76 DENSITY a/cc.
Primary Examiner-Carl D. Quarforth Assistant Examiner-R. E. Schafer Attorney-Herbert H. Goodman [5 7] ABSTRACT 'Sintered alloys of tungsten containing between about l'per 14 Claims, 3 Drawing Figures 0.20% NICKEL WEIGHT PERCENT RHENIUM PATENTEDFEBI 1972 3633.293
SHEET 1 OF 2 0.20% NICKEL DENSITY s/cc.
OI23456789IO WEIGHT PERCENT RHENIUM INVENTOR SVEN TORSTEN LENNART PETERSON BY (5W 9 ATTORNEYS HIGH-DENSITY TUNGSTEN-RIIENIUM-NICKEL ALLOYS AND ARTICLES BACKGROUND OF THE INVENTION Tungsten is widely used in industry for electrical materials such as contacts. The most widely used method for manufacturing tungsten articles is the powder metallurgic method. This conventionally involves preparation of the metal powder (or mixture of metal powders when alloys are to be prepared), reduction, pressing, presintering, and then sintering to obtain a relatively dense article. Presintering and sintering are carried out in an inert or reducing atmosphere. This is usually followed by working, i.e., cold working or hot working, such as pressing, rolling, swaging, etc., to increase density. The sequence of operations depends upon the specific article being manufactured and the properties and characteristics desired. These include electrical and tensile properties, recrystallization characteristics, grain size and orientation, porosity, nonmetallic inclusions, density, purity, etc.
It is a major advantage to obtain an article in the as sintered condition having the greatest possible density. This eliminates further working such as swaging. The advantages that follow are lower costs and minimized effect upon the recrystallization properties. It is also advantageous to obtain maximum density or the desired density at lower sintering temperatures, and particularly temperatures not higher than about 1,500-1,600 C. This results in lower cost and the ability to utilize conventional sintering furnaces. It also avoids the undesirable effects upon the electrical and/or metallographic characteristics that sometime result from extremely high temperature sintering.
The present invention provides high density tungsten-rhenium-nickel alloys and articles made therefrom.
BRIEF SUMMARY OF INVENTION Sintered high-density alloy compositions containing between about 1 and 7.5 percent rhenium and between about 0.15 and 0.3 percent nickel, and electric contacts prepared therefrom.
The preferred compositions have a density of at least 18.6 g./cc. and more preferably, a density of at least 19 g./cc.
Within the range of alloys disclosed and of electrical contact alloy compositions, preferred compositions include the following: Between 2 and 7 percent rhenium and between 0.2 and 0.3 percent nickel; between 1 and 7.5 percent rhenium and 0.3 percent nickel; between 2 and 5.5 percent rhenium and 0.2 and 0.3 percent nickel; and about 3 percent rhenium and 0.15 percent nickel.
The following compositions are also useful, although not as preferred as those listed in the preceding paragraph: Between 1 and 5.5 percent rhenium and 0.15 and 0.3 percent nickel; and between 2 and 4 percent rhenium and 0.15 percent nickel.
BRIEF DESCRIPTION OF DRAWINGS FIG, 1 is a graph relating alloy compositions to the density as sintered for the conditions and compositions in the examples herein;
FIG. 2 is a photomicrograph, 100 x, of an unetched section of the as sintered alloy composition containing 0.2 percent nickel, 3 percent rhenium and the remainder tungsten; and
FIG. 3 is a photomicrograph, 425 x, of an etched section of the same alloy.
DETAILED DESCRIPTION OF INVENTION The tungsten alloy articles of the present invention are manufactured by conventional powder metallurgic techniques. The alloy powder mixture may be prepared by admixing powders of nickel, rhenium and tungsten. They are preferably prepared by admixing reducible metal compounds of each of the metals. Nickel is preferably added as nickel carbonate or nickel oxide. Rhenium is preferably added as ammonium perrhenate. Tungsten is preferably added as tungstic oxide. Mixing is preferably carried out in a ball mill having a liquid medium, e.g., alcohol, methylene chloride, etc. After mixing has been carried out until a homogeneous mixture is attained, the mixture is removed from the ball mill, dried and reduced in hydrogen, preferably at a temperature of between about 700 and l,000 C. The resultant mixed metal powders are preferably treated by addition of a hydrocarbon material such as paraffin wax in a solvent to improve compactability. A green compact is then formed by pressing, preferably at a pressure of about 15 tons per square inch. The green compact is then presintered, preferably at a temperature of about 800 to 1,000 C. for a period of about one-half hour. Sintering is then carried out at elevated temperatures. The preferred sin tering temperature, utilizing the alloy compositions of the present invention, is between about 1,400 and 1,550 C. Sintering time is preferably between about 1 and 3 hours. This relatively low temperature sintering provides the desired density without at the same time reaching sufficiently high temperatures to undesirably affect physical and metallographic properties. Presintering and sintering are carried out in a protective atmosphere, i.e., vacuum, an inert atmosphere or a reducing atmosphere. The sintered articles may then be finished by tumbling or lapping, or, if necessary, finish machined to the desired dimensions.
The invention is further illustrated in the following examples. All parts and percentages specified in this application are by weight unless otherwise specified. a
The tungsten alloy articles of all the examples were prepared using the same procedure. A mixture of tungstic oxide, ammonium perrhenate, and nickel carbonate was thoroughly mixed in a ball mill containing ethyl alcohol. The mixed powder was then reduced in hydrogen at a temperature of between about 700 and 1,000 C. The mixed powders were then treated with a solution of paraffin wax in benzene in the conventional manner. Green compacts were formed at 15 tons per square inch pressure. The green compacts were then presintered at a temperature of between about 800 and l,000 C. for one-half hour in a hydrogen atmosphere (dewpoint 60 F.) and were then sintered in a hydrogen atmosphere (dewpoint 60 F.) at a temperature of 1,500" C. for 1 hour. During sintering, there was a shrinkage of about 45 percent by volume of the tungsten-rhenium-nickel alloys. The metal articles produced from these alloys have unusually high density, are coherent, and have a homogeneous structure, as shown in FIG. 2, a photomicrograph x) of an unetched section, and FIG. 3, a photomicrograph (425 x) of an etched section of the alloy composition 0.20 percent nickel and 3 percent rhenium.
The density of various tungsten-rhenium-nickel sintered articles is reported in table I, together with the densities of a number of different tungsten alloys (and also unalloyed tungsten) for comparative purposes.
and 7 percent rhenium and between about 0.2 and 0.3 percent nickel and having a density as sintered in excess of 19 g./cc.
3. The compositions of claim 1 containing about 0.3 percent nickel and having a density as sintered in excess of 19 g./cc.
4. The compositions of claim 1 containing between about 1 and 5.5 percent rhenium.
5. The compositions of claim 4 containing at least about 2 percent rhenium and containing at least about 0.2 percent nickel and having a density as sintered in excess of 19 g./cc.
6. The compositions of claim 4 containing between about 2 and 4 percent rhenium and containing about 0.15 percent nickel.
7. The compositions of claim 6 containing about 3 percent rhenium and having a density as sintered in excess of 19 g./cc.
8. Sintered high-density electric contacts consisting essentially of between about I and 7.5 percent rhenium, between about 0.15 and 0.3 percent nickel and the balance tungsten.
9. The electric contacts of claim 8 containing between about 2 and 7 percent rhenium and between about 0.2 and 0.3 percent nickel, and having a density in excess of IQ g./cc.
10. The electric contacts of claim 8 containing about 0.3 percent nickel and having a density in excess of l9 g./cc.
11. The electric contacts of claim 8 containing between 1 and 5.5 percent rhenium.
12. The electric contacts of claim 11 containing at least 2 percent rhenium and containing at least 0.2 percent nickel and having a density in excess of 19 g./cc.
13. The electric contacts of claim 11 containingbetween 2 andfl percent rhenium and containing about 0.l5 percent nickel.
14. The electric contacts of claim 13 containing about 3 percent rhenium and having a density in excess of 19 g./cc.

Claims (13)

  1. 2. The compositions of claim 1 containing between about 2 and 7 percent rhenium and between about 0.2 and 0.3 percent nickel and having a density as sintered in excess of 19 g./cc.
  2. 3. The compositions of claim 1 containing about 0.3 percent nickel and having a density as sintered in excess of 19 g./cc.
  3. 4. The compositions of claim 1 containing between about 1 and 5.5 percent rhenium.
  4. 5. The compositions of claim 4 containing at least about 2 percent rhenium and containing at least about 0.2 percent nickel and having a density as sintered in excess of 19 g./cc.
  5. 6. The compositions of claim 4 containing between about 2 and 4 percent rhenium and containing about 0.15 percent nickel.
  6. 7. The compositions of claim 6 containing about 3 percent rhenium and having a density as sintered in excess of 19 g./cc.
  7. 8. Sintered high-density electric contacts consisting essentially of between about 1 and 7.5 percent rhenium, between about 0.15 and 0.3 percent nickel and the balance tungsten.
  8. 9. The electric contacts of claim 8 containing between about 2 and 7 percent rhenium and between about 0.2 and 0.3 percent nickel, and having a density in excess of 19 g./cc.
  9. 10. The electric contacts of claim 8 containing about 0.3 percent nickel and having a density in excess of 19 g./cc.
  10. 11. The electric contacts of claim 8 containing between 1 and 5.5 percent rhenium.
  11. 12. The electric contacts of claim 11 containing at least 2 percent rhenium and containing at least 0.2 percent nickel and having a density in excess of 19 g./cc.
  12. 13. The electric contacts of claim 11 containing between 2 and 4 percent rhenium and containing about 0.15 percent nickel.
  13. 14. The electric contacts of claim 13 containing about 3 percent rhenium and having a density in excess of 19 g./cc.
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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3988118A (en) * 1973-05-21 1976-10-26 P. R. Mallory & Co., Inc. Tungsten-nickel-iron-molybdenum alloys
US4012230A (en) * 1975-07-07 1977-03-15 The United States Of America As Represented By The United States Energy Research And Development Administration Tungsten-nickel-cobalt alloy and method of producing same
US4115623A (en) * 1975-12-08 1978-09-19 Oleg Vadimovich Padalko Porous material for making tool-electrode and method of producing same
US4180415A (en) * 1965-06-11 1979-12-25 Minnesota Mining And Manufacturing Company Hot-junction electrode members for copper/silver chalcogenides
EP0323628A1 (en) * 1988-01-04 1989-07-12 GTE Products Corporation Fine grain tungsten heavy alloys containing additives
CN108160995A (en) * 2017-12-25 2018-06-15 安泰天龙钨钼科技有限公司 The preparation method of pure rhenium product
CN109128163A (en) * 2018-08-16 2019-01-04 北京科技大学 A method of preparing High Performance W Base Metal components
CN113604719A (en) * 2021-06-17 2021-11-05 重庆材料研究院有限公司 Preparation method of high-performance tungsten-rhenium thermocouple wire

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2157935A (en) * 1938-12-16 1939-05-09 Mallory & Co Inc P R Refractory metal compositions
US2227445A (en) * 1939-02-13 1941-01-07 Fansteel Metallurgical Corp Contact alloy and method of making same
US2466992A (en) * 1945-08-30 1949-04-12 Kurtz Jacob Tungsten nickel alloy of high density
US3359082A (en) * 1965-04-06 1967-12-19 Gen Telephone & Elect Ductile tungsten alloys

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2157935A (en) * 1938-12-16 1939-05-09 Mallory & Co Inc P R Refractory metal compositions
US2227445A (en) * 1939-02-13 1941-01-07 Fansteel Metallurgical Corp Contact alloy and method of making same
US2466992A (en) * 1945-08-30 1949-04-12 Kurtz Jacob Tungsten nickel alloy of high density
US3359082A (en) * 1965-04-06 1967-12-19 Gen Telephone & Elect Ductile tungsten alloys

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4180415A (en) * 1965-06-11 1979-12-25 Minnesota Mining And Manufacturing Company Hot-junction electrode members for copper/silver chalcogenides
US3988118A (en) * 1973-05-21 1976-10-26 P. R. Mallory & Co., Inc. Tungsten-nickel-iron-molybdenum alloys
US4012230A (en) * 1975-07-07 1977-03-15 The United States Of America As Represented By The United States Energy Research And Development Administration Tungsten-nickel-cobalt alloy and method of producing same
US4115623A (en) * 1975-12-08 1978-09-19 Oleg Vadimovich Padalko Porous material for making tool-electrode and method of producing same
EP0323628A1 (en) * 1988-01-04 1989-07-12 GTE Products Corporation Fine grain tungsten heavy alloys containing additives
CN108160995A (en) * 2017-12-25 2018-06-15 安泰天龙钨钼科技有限公司 The preparation method of pure rhenium product
CN108160995B (en) * 2017-12-25 2020-03-06 安泰天龙钨钼科技有限公司 Process for preparing pure rhenium products
CN109128163A (en) * 2018-08-16 2019-01-04 北京科技大学 A method of preparing High Performance W Base Metal components
CN113604719A (en) * 2021-06-17 2021-11-05 重庆材料研究院有限公司 Preparation method of high-performance tungsten-rhenium thermocouple wire

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