US2955145A - Thermo-electric alloys - Google Patents

Thermo-electric alloys Download PDF

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US2955145A
US2955145A US826916A US82691659A US2955145A US 2955145 A US2955145 A US 2955145A US 826916 A US826916 A US 826916A US 82691659 A US82691659 A US 82691659A US 2955145 A US2955145 A US 2955145A
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alloys
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Schrewelius Nils Gustav
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Kanthal AB
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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N10/00—Thermoelectric devices comprising a junction of dissimilar materials, i.e. devices exhibiting Seebeck or Peltier effects
    • H10N10/80—Constructional details
    • H10N10/85—Thermoelectric active materials
    • H10N10/851—Thermoelectric active materials comprising inorganic compositions
    • H10N10/854—Thermoelectric active materials comprising inorganic compositions comprising only metals
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/58—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides
    • C04B35/58085—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on silicides
    • C04B35/58092—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on silicides based on refractory metal silicides
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/62605—Treating the starting powders individually or as mixtures
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/6303—Inorganic additives
    • C04B35/6316—Binders based on silicon compounds
    • 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
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/40—Metallic constituents or additives not added as binding phase
    • C04B2235/404—Refractory metals
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5436—Particle size related information expressed by the size of the particles or aggregates thereof micrometer sized, i.e. from 1 to 100 micron
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/658—Atmosphere during thermal treatment
    • C04B2235/6582—Hydrogen containing atmosphere
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/658—Atmosphere during thermal treatment
    • C04B2235/6583—Oxygen containing atmosphere, e.g. with changing oxygen pressures
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/66—Specific sintering techniques, e.g. centrifugal sintering
    • C04B2235/661—Multi-step sintering
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/74—Physical characteristics
    • C04B2235/76—Crystal structural characteristics, e.g. symmetry
    • 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
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/0408—Light metal alloys
    • C22C1/0416—Aluminium-based alloys
    • 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
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/045—Alloys based on refractory metals
    • 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
    • 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
    • C22C32/0036—Matrix based on Al, Mg, Be or alloys thereof

Definitions

  • thermo-electric alloys which are particularly suitable for use at very elevated temperatures, and which consist essentially of an intermetallic composition containing molybdenum, silicon and aluminium.
  • thermo-electric alloys according to the present invention are distinguished from such previously known alloys in that they comprise molybdenum disilicide wherein 20-60 atomic percents of silicon have been replaced by aluminium.
  • molybdenum disilicide which is normally of the tetragonal C 11 lattice type
  • hexagonal C 40 lattice type are well known to those skilled in the art.
  • alloys according to the present invention are high mechanical strength, high oxidation resistance, and resistance to thermal shocks.
  • variations of the content of aluminium variations in the thermal E.M.F. can be readily obtained, and these variations are not accompanied by any significant deterioration of the mechanical or chemical properties of the alloys.
  • the alloys according to the present invention are distinguished from the previously known thermo-electric alloys based on molybdenum silicide.
  • thermo-electric alloys according to the invention may also, if desired, comprise admixtures of other metals.
  • up to 50 atomic percents as a maximum of molybdenum can be replaced by one or more of the metals titanium, zirconium, hafnium, tantalum, niobium, vanadium, tungsten, and chromium.
  • the composition of the thermo-electric alloys according to the present invention may thus be expressed as wherein 0.2 x 0.6 and 0 y 0.5, and M represents one or more of the metals Ti, Zr, Hf, Ta, Nb, V, W or C1.
  • the alloy has the composition Mo(Si Al When a metal M is present, y preferably has a value of at least 0.05.
  • Thermo-couples comprising the alloys according to the invention are preferably made by a powder metallurgical process by sintering after admixture with 0.5 to 20 Wt. percent of a ceramic binding substance.
  • the ceramic binding substance is composed essentially of very finely powdered silica. However, it may also contain other oxides or silicon carbide. Conveniently, the final sintering is carried out in air, in which case a certain internal oxidation takes place.
  • the ceramic component should preferably not exceed 30 percent'by weight of the material.
  • Thermocouples having one leg comprised of an alloy according to the invention, and another leg composed of MoSi for example, may also advantageously be used as heating resistors for producing high temperatures.
  • the device defined by the two legs is suitably connected to serve as a thermocouple only for the short periods when the thermo-voltage is measured and to serve as an electrical heating resistor for the remaining periods.
  • the resulting thermo-voltage may be used in practice for controlling the current supply to the resistor over a relay.
  • the welded joint between the two legs should be disposed internally of the furnace, at or adjacent a lead-in electrode, so that it is not subjected to higher temperatures than those of the furnace room.
  • thermo-couple 1600 to 1700 0:
  • the positive leg is formed as a hair pin having one portion of 6 mm. diameter which acts as a glowing zone.
  • One end of the loop is enlarged to 14 mm. and is long enough to extend out from the furnace as a cold lead-in electrode.
  • the other end is Welded to a 9 mm. negative leg, which is similarly elongated to act as a cold lead-in electrode.
  • the alloy forming the negative leg has about half as high a specific resistance at 1600 C. as the alloy forming the positive leg, this lead-in electrode will also remain cool enough without special cooling devices.
  • the welded joint will attain the same temperature as the furnace room, provided that it is disposed appropriately in the furnace, notwithstanding the fact that it is disposed adjacent the hot glowing Zone.
  • the alloy in accordance with the present invention described in the above example and used as the positive leg was formed as follows; all parts being by weight; 98 parts of a metal powder made as set forth below were admixed with two parts of bentonite as a ceramic binding substance. Then this mixture was formed, dried and placedin a metal tube and sintered at 1400" C. for 30 minutes in an atmosphere of technical hydrogenl Final sintering was carriedout at 1550 C. in air for 2 minutes.
  • the above mentionedmetal powder was of the composition (MoojjTid g)(Si0 8A1U 2 )2 and was formed in such a manner that Mo, Ti, Si and Al in theoretic quantities were heated in hydrogen gas to 1100 C. to start an exothermic reaction. The resulting sponge was then milled in a ball mill to a grain size of l-10 microns.
  • the negative leg was formed in the same manner, using 95% MoSi and .5 bentonite.
  • thermocouples formed by the use of the alloys of the present invention may have' 4- in thermo-couples for elevated temperatures in oxidizing atmospheres, said alloy being of the hexagonal C 40 lattice type and having the composition (Mo M (Si 5;Al,;) Where M is at least one of the metals Ti, Zr, Hf, Nb, Ta, V, W, Cr, x has a value of 0.2 to 0.6 and y has a value of 0 to 0.5.
  • thermo-electric alloy containing molybdenum, silicon and at least one other metal and adapted to be used in thermo-couples for elevated temperatures in oxidizing atmospheres, said alloy being ofthe hexagonal C 40 lattice type and having the composition (Mo Ti o.a o.2)z-
  • thermo-couple having a positive leg comprising an alloy having the composition (Mo M (Si Al where M is at least one of the metals Ti, Zr, H f, Nb, Ta, V, W, Cr, x has a value of 0.2 to 0.6 and y has a value of 0 to 025, and a negative leg comprising Mosi r 4.
  • the alloy has the composition (Mo Ti )(Si Al References Cited in the file of'this'patent UNITED STATES PATENTS 2,745,928 Glasser May 5, 1955

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Description

2,955,145 Patented Oct. 4, 1960 THERMO-ELE CTRIC ALLOYS Nils Gustav Schrewelius, Hallstahammar, Sweden, assignor to AB Kanthal, Hallstahammar, Sweden, a corporation of Sweden N Drawing. Filed .luly1'4, 1959, Ser. No. 826,916 Claims priority, application Sweden July 16, 1958 4 Claims. (Cl. "136-5) 7 This invention relates to thermo-electric alloys which are particularly suitable for use at very elevated temperatures, and which consist essentially of an intermetallic composition containing molybdenum, silicon and aluminium.
It is known (J. Appl. Phys. 24, p. 498, 1953), that MoSi within the range from -60 C. to +600 C. exhibits, with respect to platinum, a thermal which corresponds approximately to that of copper. Thus, highly temperature-resistant molybdenum disilicide can be used in a thermo-couple. It is also known (Austrian patent specification 193,632) that molybdenum disilicide with 3040% Si and various additions of other scaleresistant silicides or oxides or silicon carbide may be used in thermo-couples at elevated temperatures. Additions suggested in this patent are titanium silicide, tungsten silicide, chromiumsilicide, aluminium oxide, thorium oxide, titanium oxide, and zirconium oxide. Up to 25% of the silicon atoms of the molybdenum silicide may be replaced by carbon, boron or nitrogen.
"the thermo-electric alloys according to the present invention are distinguished from such previously known alloys in that they comprise molybdenum disilicide wherein 20-60 atomic percents of silicon have been replaced by aluminium. As a result, the crystal structure of the molybdenum disilicide, which is normally of the tetragonal C 11 lattice type, is converted entirely to the hexagonal C 40 lattice type. These lattice types are well known to those skilled in the art. (Compare Schwarzkopf et al., Refractory Hard Metals, 1953.) This conversion of the crystal structure results, surprisingly, in a considerably increased thermal for the alloys according to the present invention with respect to pure M0Si for example. Other advantages of these alloys are high mechanical strength, high oxidation resistance, and resistance to thermal shocks. By variations of the content of aluminium variations in the thermal E.M.F. can be readily obtained, and these variations are not accompanied by any significant deterioration of the mechanical or chemical properties of the alloys. In this respect, the alloys according to the present invention are distinguished from the previously known thermo-electric alloys based on molybdenum silicide.
The thermo-electric alloys according to the invention may also, if desired, comprise admixtures of other metals. Thus, up to 50 atomic percents as a maximum of molybdenum can be replaced by one or more of the metals titanium, zirconium, hafnium, tantalum, niobium, vanadium, tungsten, and chromium. The composition of the thermo-electric alloys according to the present invention may thus be expressed as wherein 0.2 x 0.6 and 0 y 0.5, and M represents one or more of the metals Ti, Zr, Hf, Ta, Nb, V, W or C1.
When the alloy contains no metal M, i.e. when y is 0,
then the alloy has the composition Mo(Si Al When a metal M is present, y preferably has a value of at least 0.05.
Thermo-couples comprising the alloys according to the invention are preferably made by a powder metallurgical process by sintering after admixture with 0.5 to 20 Wt. percent of a ceramic binding substance. Preferably, the ceramic binding substance is composed essentially of very finely powdered silica. However, it may also contain other oxides or silicon carbide. Conveniently, the final sintering is carried out in air, in which case a certain internal oxidation takes place. The ceramic component should preferably not exceed 30 percent'by weight of the material.
Thermocouples having one leg comprised of an alloy according to the invention, and another leg composed of MoSi for example, may also advantageously be used as heating resistors for producing high temperatures. In this case, the device defined by the two legs is suitably connected to serve as a thermocouple only for the short periods when the thermo-voltage is measured and to serve as an electrical heating resistor for the remaining periods. The resulting thermo-voltage may be used in practice for controlling the current supply to the resistor over a relay. Preferably the welded joint between the two legs should be disposed internally of the furnace, at or adjacent a lead-in electrode, so that it is not subjected to higher temperatures than those of the furnace room.
The following example illustrates the use of alloys according to the invention in a thermo-couple for 1600 to 1700 0:
The thermal increased regularly with the temperature and attained, inter alia, the following values:
Millivolts 800 C. 10 1000" C. 14 1200 C. l9 1400 C 24 1600 C 31 Both legs were 6 mm. cylindrical rods, made by extrusion and sintering, and joined by resistance butt welding. The most oxidation resistant negative leg may also, as an alternative, be formed as a tube which is closed at one end and surrounds the rod-shaped positive leg.
The above described leg combination may also be used as an electrical heating resistor and should then have the following dimensions: the positive leg is formed as a hair pin having one portion of 6 mm. diameter which acts as a glowing zone. One end of the loop is enlarged to 14 mm. and is long enough to extend out from the furnace as a cold lead-in electrode. The other end is Welded to a 9 mm. negative leg, which is similarly elongated to act as a cold lead-in electrode. As the alloy forming the negative leg has about half as high a specific resistance at 1600 C. as the alloy forming the positive leg, this lead-in electrode will also remain cool enough without special cooling devices. For the same reason, the welded joint will attain the same temperature as the furnace room, provided that it is disposed appropriately in the furnace, notwithstanding the fact that it is disposed adjacent the hot glowing Zone.
The alloy in accordance with the present invention described in the above example and used as the positive leg, was formed as follows; all parts being by weight; 98 parts of a metal powder made as set forth below were admixed with two parts of bentonite as a ceramic binding substance. Then this mixture was formed, dried and placedin a metal tube and sintered at 1400" C. for 30 minutes in an atmosphere of technical hydrogenl Final sintering was carriedout at 1550 C. in air for 2 minutes. The above mentionedmetal powder was of the composition (MoojjTid g)(Si0 8A1U 2 )2 and was formed in such a manner that Mo, Ti, Si and Al in theoretic quantities were heated in hydrogen gas to 1100 C. to start an exothermic reaction. The resulting sponge was then milled in a ball mill to a grain size of l-10 microns. The negative leg was formed in the same manner, using 95% MoSi and .5 bentonite.
- It'will be understood that thermocouples formed by the use of the alloys of the present invention may have' 4- in thermo-couples for elevated temperatures in oxidizing atmospheres, said alloy being of the hexagonal C 40 lattice type and having the composition (Mo M (Si 5;Al,;) Where M is at least one of the metals Ti, Zr, Hf, Nb, Ta, V, W, Cr, x has a value of 0.2 to 0.6 and y has a value of 0 to 0.5.
2. A thermo-electric alloy containing molybdenum, silicon and at least one other metal and adapted to be used in thermo-couples for elevated temperatures in oxidizing atmospheres, said alloy being ofthe hexagonal C 40 lattice type and having the composition (Mo Ti o.a o.2)z-
3. A thermo-couple having a positive leg comprising an alloy having the composition (Mo M (Si Al where M is at least one of the metals Ti, Zr, H f, Nb, Ta, V, W, Cr, x has a value of 0.2 to 0.6 and y has a value of 0 to 025, and a negative leg comprising Mosi r 4. A thermo-couple as defined in claim 3, wherein the alloy has the composition (Mo Ti )(Si Al References Cited in the file of'this'patent UNITED STATES PATENTS 2,745,928 Glasser May 5, 1955

Claims (1)

1. A THERMO-ELECTRIC ALLOY CONTAINING MOLYBDENUM, SILICON AND AT LEAST ONE OTHER METAL AND ADAPTED TO BE USED IN THERMO-COUPLES FOR ELEVATED TEMPERATURE IN OXIDIZING ATMOSPHERES, SAID ALLOY BEING OF THE HEXAGONAL C 40 LATTICE TYPE AND HAVING THE COMPOSITION (MO1-YMY)(SI1-XALX)2, WHERE M IS AT LEAST ONE OF THE METALS, TI, ZR, HF, NB, TA, V, W, CR, X HAS A VALUE OF 0.2 TO 0.6 AND Y HAS A VALUE OF 0 TO 0.05.
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Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2998394A (en) * 1960-05-25 1961-08-29 Union Carbide Corp Electrical resistor composition
US3051924A (en) * 1958-07-05 1962-08-28 Kanthal Ab Sintered electric resistance heating elements and methods of producing such elements
US3072733A (en) * 1961-07-17 1963-01-08 Sasaki Yozo Thermoelectric generator
US3248346A (en) * 1961-10-19 1966-04-26 Kanthal Ab Heat-resistant and oxidation-proof materials containing molybdenum disilicide
US3256699A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256697A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256701A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256696A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256700A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256702A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256698A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3275572A (en) * 1961-10-11 1966-09-27 Ruben Samuel Refractory composition and electrical resistance made therefrom
US3285018A (en) * 1963-05-27 1966-11-15 Monsanto Co Two-phase thermoelectric body comprising a silicon-carbon matrix
US3285017A (en) * 1963-05-27 1966-11-15 Monsanto Co Two-phase thermoelectric body comprising a silicon-germanium matrix
US3285019A (en) * 1963-05-27 1966-11-15 Monsanto Co Two-phase thermoelectric body comprising a lead-tellurium matrix
US3298777A (en) * 1961-12-12 1967-01-17 Du Pont Thermoelectric compositions of nbxta1-xsiyge2-y
US3330703A (en) * 1962-05-18 1967-07-11 Podolsky Leon Thermoelectric elements of oriented graphite containing spaced bands of metal atoms
US3343373A (en) * 1963-05-27 1967-09-26 Monsanto Co Two-phase thermo-electric body comprising a boron-carbon matrix
US3523832A (en) * 1965-06-11 1970-08-11 Siemens Ag Thermogenerator with germanium-silicon semiconductors
US4486651A (en) * 1982-01-27 1984-12-04 Nippon Soken, Inc. Ceramic heater
US4644133A (en) * 1985-02-28 1987-02-17 Nippondenso Co., Ltd. Ceramic heater
US5156688A (en) * 1991-06-05 1992-10-20 Xerox Corporation Thermoelectric device
US5474619A (en) * 1994-05-04 1995-12-12 The United States Of America As Represented By The Secretary Of Commerce Thin film high temperature silicide thermocouples
US6563095B1 (en) * 1999-05-20 2003-05-13 Sandvik Ab Resistance-heating element
US20050236399A1 (en) * 2002-04-05 2005-10-27 Sandvik Ab Method of marking a heating element of the molybdenum silicide type and a heating element
US20050252909A1 (en) * 2002-04-05 2005-11-17 Jan Andersson Electrical heating resistance element

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US2745928A (en) * 1952-10-06 1956-05-15 American Electro Metal Corp Heater bodies and their production

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* Cited by examiner, † Cited by third party
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Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3051924A (en) * 1958-07-05 1962-08-28 Kanthal Ab Sintered electric resistance heating elements and methods of producing such elements
US2998394A (en) * 1960-05-25 1961-08-29 Union Carbide Corp Electrical resistor composition
US3072733A (en) * 1961-07-17 1963-01-08 Sasaki Yozo Thermoelectric generator
US3275572A (en) * 1961-10-11 1966-09-27 Ruben Samuel Refractory composition and electrical resistance made therefrom
US3248346A (en) * 1961-10-19 1966-04-26 Kanthal Ab Heat-resistant and oxidation-proof materials containing molybdenum disilicide
US3298777A (en) * 1961-12-12 1967-01-17 Du Pont Thermoelectric compositions of nbxta1-xsiyge2-y
US3256701A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256696A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256700A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256702A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256698A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256697A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3256699A (en) * 1962-01-29 1966-06-21 Monsanto Co Thermoelectric unit and process of using to interconvert heat and electrical energy
US3330703A (en) * 1962-05-18 1967-07-11 Podolsky Leon Thermoelectric elements of oriented graphite containing spaced bands of metal atoms
US3285019A (en) * 1963-05-27 1966-11-15 Monsanto Co Two-phase thermoelectric body comprising a lead-tellurium matrix
US3285017A (en) * 1963-05-27 1966-11-15 Monsanto Co Two-phase thermoelectric body comprising a silicon-germanium matrix
US3285018A (en) * 1963-05-27 1966-11-15 Monsanto Co Two-phase thermoelectric body comprising a silicon-carbon matrix
US3343373A (en) * 1963-05-27 1967-09-26 Monsanto Co Two-phase thermo-electric body comprising a boron-carbon matrix
US3523832A (en) * 1965-06-11 1970-08-11 Siemens Ag Thermogenerator with germanium-silicon semiconductors
US4486651A (en) * 1982-01-27 1984-12-04 Nippon Soken, Inc. Ceramic heater
US4644133A (en) * 1985-02-28 1987-02-17 Nippondenso Co., Ltd. Ceramic heater
US5156688A (en) * 1991-06-05 1992-10-20 Xerox Corporation Thermoelectric device
US5474619A (en) * 1994-05-04 1995-12-12 The United States Of America As Represented By The Secretary Of Commerce Thin film high temperature silicide thermocouples
US6563095B1 (en) * 1999-05-20 2003-05-13 Sandvik Ab Resistance-heating element
US20050236399A1 (en) * 2002-04-05 2005-10-27 Sandvik Ab Method of marking a heating element of the molybdenum silicide type and a heating element
US20050252909A1 (en) * 2002-04-05 2005-11-17 Jan Andersson Electrical heating resistance element
US7164103B2 (en) * 2002-04-05 2007-01-16 Sandvik Intellectual Property Aktiebolag Electrical heating resistance element
US8053710B2 (en) * 2002-04-05 2011-11-08 Sandvik Intellectual Property Aktiebolag Method of making a heating element of the molybdenum silicide type and a heating element

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