WO2019177147A1 - Élément de conversion thermoélectrique - Google Patents

Élément de conversion thermoélectrique Download PDF

Info

Publication number
WO2019177147A1
WO2019177147A1 PCT/JP2019/010818 JP2019010818W WO2019177147A1 WO 2019177147 A1 WO2019177147 A1 WO 2019177147A1 JP 2019010818 W JP2019010818 W JP 2019010818W WO 2019177147 A1 WO2019177147 A1 WO 2019177147A1
Authority
WO
WIPO (PCT)
Prior art keywords
electrode
thermoelectric conversion
silicide
conversion element
element body
Prior art date
Application number
PCT/JP2019/010818
Other languages
English (en)
Japanese (ja)
Inventor
中田　嘉信
Original Assignee
三菱マテリアル株式会社
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 JP2019040845A external-priority patent/JP7242999B2/ja
Application filed by 三菱マテリアル株式会社 filed Critical 三菱マテリアル株式会社
Priority to US16/957,968 priority Critical patent/US11152554B2/en
Priority to KR1020207019226A priority patent/KR20200130806A/ko
Priority to CN201980007644.4A priority patent/CN111630672A/zh
Priority to EP19768346.9A priority patent/EP3767689A4/fr
Publication of WO2019177147A1 publication Critical patent/WO2019177147A1/fr

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • 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
    • 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
    • C22C1/05—Mixtures of metal powder with non-metallic powder
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C9/00—Alloys based on copper
    • C22C9/10—Alloys based on copper with silicon as the next major constituent
    • 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
    • H10N10/01—Manufacture or treatment
    • 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
    • H10N10/81—Structural details of the junction
    • H10N10/817—Structural details of the junction the junction being non-separable, e.g. being cemented, sintered or soldered
    • 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

Definitions

  • thermoelectric conversion element including an element main body made of a thermoelectric conversion material of a silicide compound and electrodes formed on one surface of the element main body and the other surface facing each other.
  • thermoelectric conversion elements made of thermoelectric conversion materials are electronic elements that can convert heat and electricity to each other using phenomena such as the Seebeck effect and Peltier effect.
  • the Seebeck effect is an effect of converting thermal energy into electric energy, and is a phenomenon in which an electromotive force is generated when a temperature difference is generated between both ends of the thermoelectric conversion material. Such electromotive force is determined by the characteristics of the thermoelectric conversion material. In recent years, thermoelectric power generation utilizing this effect has been actively developed.
  • thermoelectric conversion material As an index representing the characteristics of such a thermoelectric conversion element (thermoelectric conversion material), for example, the power factor (PF) expressed by the following formula (1) or the dimensionless figure of merit expressed by the following formula (2) (ZT) is used.
  • PF S 2 ⁇ (1)
  • ZT S 2 ⁇ T / ⁇ (2)
  • T absolute temperature (K)
  • thermoelectric conversion material constituting the element body include silicide-based compounds such as magnesium silicide.
  • thermoelectric conversion element described above has a structure in which electrodes are formed on one end side and the other end side of a thermoelectric conversion material.
  • Nickel is used as an electrode formed on the element body made of a thermoelectric conversion material of a silicide-based compound such as magnesium silicide. This is because the thermal expansion coefficient of magnesium silicide (Mg 2 Si) at room temperature (15.5 ⁇ 10 ⁇ 6 (/ ° C.)) and the thermal expansion coefficient of nickel at room temperature (15.2 ⁇ 10 ⁇ 6 (/ ° C)) is approximate.
  • thermoelectric conversion element when used in an intermediate temperature range (300 ° C. or more and 600 ° C. or less), Si of the silicide compound of the element body diffuses to the electrode side, and nickel of the electrode becomes nickel silicide. Since this nickel silicide has a thermal expansion coefficient at room temperature of 12.0 ⁇ 10 ⁇ 6 (/ ° C.), the difference in thermal expansion coefficient from the element body made of a thermoelectric conversion material of a silicide compound increases. There was a risk of cracks occurring in the element body. Further, the composition in the vicinity of the interface region with the electrode of the element body changes, and there is a risk that the electrical resistance increases or the strength decreases.
  • Patent Document 1 proposes a thermoelectric conversion element in which an intermediate layer made of a refractory metal silicide is formed between an element body made of a thermoelectric conversion material and an electrode. In this thermoelectric conversion element, diffusion of elements between the element body and the electrode is suppressed by an intermediate layer made of refractory metal silicide.
  • Patent Document 2 proposes a thermoelectric conversion element using a mixture of nickel silicide and metallic nickel as an electrode.
  • the intermediate layer made of refractory metal silicide is formed by vapor deposition, sputtering, or CVD, and the intermediate layer cannot be formed efficiently. Also, it has been difficult to form a thick intermediate layer. For this reason, there is a possibility that the electrode element cannot be sufficiently prevented from diffusing into the element body by the intermediate layer.
  • nickel silicide is used as an electrode.
  • nickel silicide has a large difference in thermal expansion coefficient from the element main body made of magnesium silicide or the like, and heat during manufacture is low. There was a possibility that the element main body and the electrode were cracked by the thermal stress resulting from the history.
  • metallic nickel is in direct contact with the element body made of magnesium silicide or the like, Si in the element body diffuses to the metallic nickel side, the composition in the vicinity of the interface region of the element body changes, and the electrical resistance is high. Or the strength may be reduced.
  • the present invention has been made in view of the above-described circumstances, and the element body made of a thermoelectric conversion material of a silicide compound and the electrode are reliably bonded, the electric resistance at the bonding interface is sufficiently low, and the element It aims at providing the thermoelectric conversion element which can suppress that a main body and an electrode generate
  • thermoelectric conversion element of the present invention includes an element body made of a thermoelectric conversion material of a silicide compound, and electrodes formed on one surface of the element body and the other surface facing each other.
  • the electrode is made of a sintered body of copper silicide, and the electrode and the element body are directly joined.
  • thermoelectric conversion element since the electrode is composed of a sintered body of copper silicide, the difference in thermal expansion coefficient from the element main body made of a thermoelectric conversion material of a silicide compound can be reduced. Since copper silicide has a relatively low melting point, a liquid phase is generated in at least a part of copper silicide when a sintered body to be an electrode is formed, and thermal strain can be released. Therefore, it can suppress that a crack arises in an element main part and an electrode at the time of manufacture. When forming a sintered body to be an electrode, the entire copper silicide may be in a liquid phase.
  • the electrode and the element main body are directly joined, and as described above, a liquid phase is generated in at least a part of the copper silicide when the sintered body to be the electrode is formed.
  • the element main body can be sufficiently bonded, and the electrical resistance at the interface can be suppressed sufficiently low.
  • thermoelectric conversion element of the present invention a metal layer may be formed on the surface of the electrode opposite to the element body.
  • the metal layer formed on the surface opposite to the element body can improve the bondability with the terminal.
  • the thickness of the electrode is preferably in the range of 10 ⁇ m or more and 300 ⁇ m or less.
  • the rigidity of the electrode does not become higher than necessary, and the occurrence of cracks in the element body during manufacturing can be suppressed.
  • the electrical conductivity in an electrode is securable by making the thickness of the said electrode 10 micrometers or more.
  • the electrode is composed of a sintered body of copper silicide, and the atomic ratio Si / Cu of Si / Cu in the copper silicide is in the range of 0.12 to 0.4. It is preferable to be inside. In this case, since the Si / Cu atomic ratio Si / Cu in the copper silicide constituting the electrode is in the range of 0.12 or more and 0.4 or less, it is possible to ensure high electrical conductivity in the electrode and to manufacture the electrode. Occurrence of cracks in the element body at the time can be suppressed.
  • thermoelectric conversion element of this invention it is preferable that the said electrode is comprised with the sintered compact of the copper silicide, and the porosity in the said copper silicide is 60% or less. In this case, since the porosity of the copper silicide constituting the electrode is 60% or less, it is possible to suppress an increase in electrical resistance.
  • the element body made of the thermoelectric conversion material of the silicide compound and the electrode are reliably bonded, the electrical resistance at the interface is sufficiently low, and the occurrence of cracks in the element body and the electrode can be suppressed.
  • thermoelectric conversion element which is 1st embodiment of this invention, and the thermoelectric conversion module using this thermoelectric conversion element. It is a flowchart which shows an example of the manufacturing method of the thermoelectric conversion element which is one Embodiment of this invention. It is sectional drawing which shows an example of the sintering apparatus used with the manufacturing method of the thermoelectric conversion element shown in FIG. It is explanatory drawing which shows the measurement means of the electrical resistance in the Example of this invention.
  • thermoelectric conversion element according to an embodiment of the present invention will be described with reference to the accompanying drawings.
  • the following embodiments are specifically described for better understanding of the gist of the invention, and do not limit the present invention unless otherwise specified.
  • drawings used in the following description in order to make the features of the present invention easier to understand, there is a case where a main part is shown in an enlarged manner for the sake of convenience. Not necessarily.
  • FIG. 1 shows a thermoelectric conversion element 10 according to a first embodiment of the present invention, and a thermoelectric conversion module 1 using the thermoelectric conversion element 10.
  • a thermoelectric conversion module 1 shown in FIG. 1 includes a thermoelectric conversion element 10 and terminals 3 and 3 disposed on one surface and the other surface of the thermoelectric conversion element 10.
  • the thermoelectric conversion element 10 includes an element main body 11 made of a thermoelectric conversion material, and electrodes 15 and 15 formed on one surface and the other surface of the element main body 11, respectively. As shown in FIG. 1, the element body 11 is formed in a columnar shape, and electrodes 15 and 15 are disposed on both end surfaces of the columnar shape.
  • the shape of the element body 11 is not limited, but may be a rectangular parallelepiped shape, a cylindrical shape, a polygonal column shape, an elliptical column shape, or the like. Both surfaces of the element body 11 to which the electrodes 15 and 15 are bonded may be parallel to each other or may be slightly inclined.
  • thermoelectric conversion material constituting the element body 11 is made of, for example, a silicide compound, and in the present embodiment, the thermoelectric conversion material is preferably made of a sintered body of magnesium silicide (Mg 2 Si).
  • silicide compounds that can be used in addition to magnesium silicide include silicon germanium (Si—Ge) total solid solution, manganese silicon (Mn—Si), and iron silicon (Fe—Si).
  • the thermoelectric conversion material constituting the element body 11 includes at least one of Li, Na, K, B, Al, Ga, In, N, P, As, Sb, Bi, Ag, Cu, and Y as a dopant. May be included. When the dopant is included, the total content in the element body 11 is preferably 0.1% by mass or more and 3.0% by mass or less, but is not limited to this range.
  • the electrode 15 is composed of a sintered body of copper silicide, and the electrode 15 and the element body 11 are directly joined.
  • the electrode 15 in this example has the same planar shape as the end face of the element body 11.
  • a metal layer 16 is formed on the surface of the electrode 15 on the side opposite to the element body 11. That is, the metal layer 16 is disposed between the electrode 15 and the terminal 3.
  • the metal layer 16 in this example has the same planar shape as the electrode 15.
  • the thickness of the electrode 15 made of a copper silicide sintered body is preferably in the range of 10 ⁇ m to 300 ⁇ m. If the thickness of the electrode 15 composed of a sintered body of copper silicide is 10 ⁇ m or more, the electrical conductivity in the electrode 15 can be ensured. If the thickness of the electrode 15 composed of a sintered body of copper silicide is 300 ⁇ m or less, the rigidity of the electrode 15 is not increased more than necessary, and the occurrence of cracks in the element body 11 during manufacturing can be suppressed.
  • the lower limit of the thickness of the electrode 15 made of a sintered copper silicide is more preferably 50 ⁇ m or more.
  • the upper limit of the thickness of the electrode 15 made of a copper silicide sintered body is more preferably 150 ⁇ m or less.
  • the Si / Cu atomic ratio Si / Cu is preferably in the range of 0.12 to 0.4.
  • the copper silicide constituting the electrode 15 is fired by mixing copper silicide powders having a plurality of compositions (Si / Cu), and the average value thereof is adjusted to be within the above-described range.
  • specific examples of copper silicide include Cu 3 Si (atomic ratio 1/3) and Cu 7 Si (atomic ratio 1/7), which can be mixed and used as a sintering raw material.
  • the atomic ratio Si / Cu of the copper silicide constituting the electrode 15 is 0.4 or less, single-phase sintering material is Cu 3 Si, or a Cu 3 Si, copper silicide consisting of minor amounts of other composition It is a copper silicide powder formed from a mixture. By melting the whole or a part of the sintering raw material, electrical conduction in the electrode 15 can be secured, and cracking of the element body 11 at the time of manufacture can be suppressed.
  • the lower limit of the number ratio Si / Cu of the copper silicide constituting the electrode 15 is more preferably 0.13 or more.
  • the upper limit of the atomic ratio Si / Cu of the copper silicide constituting the electrode 15 is more preferably 0.35 or less.
  • a copper silicide powder having a plurality of compositions Si / Cu
  • a part of the electrode 15 has a liquid phase solidification part formed by solidification of the liquid phase.
  • This liquid phase solidification part has fewer voids and a locally higher density than the region where no liquid phase is formed.
  • the porosity of the electrode 15 as a whole is not limited in the present invention, but is preferably 0% by volume or more and 60% by volume or less, more preferably 0% by volume or more and 50% by volume or less.
  • the distribution of the liquid phase solidified portion in the electrode 15 is not limited, it is preferable from the viewpoint of stress relaxation that the liquid phase solidified portion is concentrated and distributed in a layered manner on the element body 11 side.
  • the liquid phase solidified portions may be distributed substantially uniformly over the entire area of the electrode 15, or may be concentrated and distributed in a layered manner on the metal layer 16 side.
  • the porosity of the electrode 15 was determined by the following method. First, the weight of the silicide sintered body before forming the copper silicide electrode is measured. Next, after forming the electrodes, the thicknesses of the electrodes on both sides are measured at five locations with an optical microscope or a scanning electron microscope, and the average is obtained. Next, the size (vertical width, horizontal width, radius, etc.) of the electrode surfaces on both surfaces is measured with a caliper or a micrometer, and the surface areas of the electrode surfaces on both surfaces are obtained. From this surface area and the thickness of each electrode on both sides, the volume of the electrode part on each side is obtained.
  • the weight of the state in which the silicide sintered body and the electrode are integrated is weighed, and the weight of the electrode is obtained by subtracting the weight of the silicide sintered body.
  • the density of the electrode parts is determined from the weight and volume of the electrode parts on both sides. The density thus obtained is taken as the measured density.
  • the true density was estimated and calculated from the average composition obtained by analyzing the electrode layer with EPMA, and the porosity was determined from the equation (100 ⁇ (measured density / true density ⁇ 100) (%)).
  • the metal layer 16 is made of, for example, a metal having excellent conductivity, such as nickel, aluminum, or copper. In the present embodiment, the metal layer 16 is preferably made of aluminum.
  • the metal layer 16 is formed by bonding a metal foil or the like to the electrode 15 by, for example, brazing.
  • the thickness of the metal layer 16 is not limited, but is preferably in the range of 0.1 mm to 2.0 mm.
  • the terminal 3 is formed of a metal material having excellent conductivity, for example, a plate material such as copper or aluminum. In the present embodiment, it is preferable to use an aluminum rolled plate.
  • the metal layer 16 formed on the electrode 15 and the terminal 3 can be joined by, for example, Ag brazing, Ag plating, or the like.
  • the pair of terminals 3 of this embodiment extend to opposite sides as viewed from the element body 11 and are arranged in parallel to each other, but the present invention is not limited to this arrangement.
  • thermoelectric conversion element 10 described above will be described with reference to FIGS.
  • silicide compound powder preparation step S01 First, a silicide compound powder (magnesium silicide powder) serving as a parent phase of a thermoelectric conversion material constituting the element body is prepared.
  • a silicide compound ingot (magnesium silicide) is manufactured, and this is pulverized and sieved to manufacture a silicide compound powder (magnesium silicide powder) having a predetermined particle size.
  • Commercially available magnesium compound powder (magnesium silicide powder) may be used.
  • the average particle diameter of the silicide compound powder (magnesium silicide powder) is preferably in the range of 0.5 ⁇ m to 100 ⁇ m.
  • the sintering apparatus (electric current sintering apparatus 100) shown in FIG. 3 includes, for example, a pressure-resistant housing 101, a vacuum pump 102 that depressurizes the inside of the pressure-resistant housing 101, and a hollow cylinder disposed in the pressure-resistant housing 101.
  • a carbon plate 107 and a carbon sheet 108 are disposed between the electrode portions 105a and 105b and the sintering raw material powder Q, respectively.
  • a thermometer, a displacement meter, etc. are provided.
  • a heater 109 is disposed on the outer peripheral side of the carbon mold 103.
  • the heater 109 is disposed on four side surfaces so as to cover the entire outer peripheral side of the carbon mold 103.
  • a carbon heater a nichrome wire heater, a molybdenum heater, a Kanthal wire heater, a high frequency heater, or the like can be used.
  • the raw material powder Q is filled into the carbon mold 103 of the electric current sintering apparatus 100 shown in FIG.
  • the carbon mold 103 is covered with a graphite sheet or a carbon sheet.
  • a direct current is passed between the pair of electrode portions 105a and 105b, and a current is passed through the sintered raw material powder Q to raise the temperature by self-heating (electric heating).
  • the movable electrode portion 105a is moved toward the sintering raw material powder Q, and the sintering raw material powder Q is pressurized at a predetermined pressure with the fixed electrode portion 105b.
  • the heater 109 is heated.
  • the sintered raw material powder Q is sintered by self-heating of the sintered raw material powder Q, heat from the heater 109, and pressurization.
  • the sintering conditions in the element body sintering step S02 are such that the heating temperature of the sintering raw material powder Q is in the range of 650 ° C. or more and 1030 ° C. or less, and the holding time at this heating temperature is 0 minute or more (for example, 1 second or longer) and 3 minutes or shorter.
  • the pressure load is 15 MPa or more and 60 MPa or less.
  • the atmosphere in the pressure-resistant housing 101 is preferably an inert atmosphere such as an argon atmosphere or a vacuum atmosphere. In a vacuum atmosphere, the pressure is preferably 5 Pa or less.
  • the element body sintering step S02 it is preferable to change the polarities of the one electrode portion 105a and the other electrode portion 105b at a predetermined time interval when a direct current is passed through the sintered raw material powder Q. That is, the state where one electrode portion 105a is energized with the anode and the other electrode portion 105b as the cathode and the state where one electrode portion 105a is energized with the cathode and the other electrode portion 105b as the anode are alternately performed.
  • the element body 11 (thermoelectric conversion material) is manufactured through the above steps. By alternately switching the direction of the current, there is an advantage that the uniformity of the element body 11 is improved.
  • the carbon mold 103 of the electric current sintering apparatus 100 is filled with copper silicide powder and a sintered body of a silicide compound.
  • the carbon sheets on both end faces and side faces of the sintered body of the silicide compound are removed, and both end faces of the sintered body are polished with abrasive paper.
  • a carbon plate 107 and a carbon sheet 108 are inserted into the carbon mold 103 and filled with a predetermined amount of copper silicide powder, then a sintered body of a silicide compound is inserted, and a predetermined amount of copper silicide powder is further filled thereon. Then, the carbon plate 107 and the carbon sheet 108 are disposed thereon.
  • the copper silicide powder it is preferable to use a powder having an average particle size of 0.5 ⁇ m or more and 50 ⁇ m or less.
  • a mixture of copper silicide powders having a plurality of compositions (mass ratio Si / Cu) is used as the copper silicide powder.
  • Electrode sintering step S04 Using the power source device 106 of the electric current sintering apparatus 100, the temperature is raised by self-heating by applying a direct current between the pair of electrode portions 105a and 105b (electric current heating). Pressurization is performed at a predetermined pressure using the pair of electrode portions 105a and 105b. Further, the heater 109 is heated. Thus, the copper silicide powder is sintered to form the electrode 15 and the electrode 15 and the element body 11 are directly joined.
  • the sintering condition in the electrode sintering step S04 is that the heating temperature is in the range of 650 ° C. or higher and 850 ° C. or lower, and the holding time at this heating temperature is 0 minute or longer (for example, 1 second or longer), 3 minutes. It is preferable to be within the following range.
  • the pressure load is preferably in the range of 2 MPa to 40 MPa.
  • the atmosphere in the pressure-resistant housing 101 is preferably an inert atmosphere such as an argon atmosphere or a vacuum atmosphere. In a vacuum atmosphere, the pressure is preferably 5 Pa or less.
  • the copper silicide powder since a mixture of copper silicide powders having a plurality of compositions (atomic ratio Si / Cu) is used, a liquid phase is partially generated in the electrode sintering step S04, A liquid phase solidified portion formed by solidifying the liquid phase is formed on a part of the electrode 15.
  • the bondability between the element body 11 and the electrode 15 is improved.
  • the metal layer 16 is formed on the surface of the electrode 15 opposite to the element body 11.
  • the metal layer 16 can be formed by joining a metal foil material having excellent conductivity such as nickel, aluminum, copper, etc. to the electrode 15 using, for example, a brazing material.
  • a brazing material Ag brazing such as Ag—Cu—Zn—Cd, Ag—Cu—Sn, or the like can be used.
  • a 0.5 mm thick aluminum rolled plate is cut to the same size as the cross section of the thermoelectric element, and the metal layer 16 is formed on the electrode 15 using Ag brazing (BAg-1A (JIS)). did.
  • thermoelectric conversion element 10 in which the element body 11 made of a silicide-based thermoelectric conversion material and the electrode 15 made of a copper silicide sintered body are directly bonded is manufactured by the above-described steps.
  • thermoelectric conversion element 10 since the electrode 15 is composed of a sintered body of copper silicide, the thermal expansion coefficient of the element main body 11 made of a thermoelectric conversion material of a silicide compound (magnesium silicide) is reduced. The difference can be reduced, and the occurrence of cracks due to the thermal history during manufacture and use can be suppressed.
  • the copper silicide since the copper silicide has a relatively low melting point, a liquid phase is generated in part when the sintered body is formed, and thermal strain can be released, and the element main body 11 and the electrode 15 are cracked during manufacturing. It can be suppressed.
  • the electrode 15 and the element body 11 are directly bonded, and a liquid phase is generated in part when forming the sintered body, the bondability between the electrode 15 and the element body 11 is improved. The electrical resistance at the interface can be kept sufficiently low.
  • the terminal 3 and the electrode 15 can be joined relatively easily, and the terminal 3 and the electrode 15 can be joined. 15 can be improved.
  • the thickness of the electrode 15 is in the range of 10 ⁇ m or more and 300 ⁇ m or less, the rigidity of the electrode 15 is not unnecessarily high, and the element main body 11 is not cracked during manufacturing. While being able to suppress, the electrical conductivity in the electrode 15 is securable.
  • the Si / Cu atomic ratio Si / Cu in the copper silicide constituting the electrode 15 is in the range of 0.12 to 0.4, the electrical conductivity in the electrode 15 is Can be ensured, and the occurrence of cracks in the element body 11 during manufacturing can be suppressed.
  • thermoelectric conversion element As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention.
  • thermoelectric conversion element Although it demonstrated as what comprises the thermoelectric conversion element and thermoelectric conversion module of a structure as shown in FIG. 1, it is not limited to this, The thermoelectric conversion element of this invention may be used.
  • the structure and arrangement of the terminals are not particularly limited.
  • the silicide compound constituting the element body is described as magnesium silicide (Mg 2 Si).
  • Mg 2 Si magnesium silicide
  • the present invention is not limited to this, and any other composition may be used as long as it has thermoelectric properties. It may be a silicide compound.
  • the copper silicide powder of a several composition (atomic ratio Si / Cu) was used as a copper silicide powder
  • the copper silicide powder of a single composition is used. be able to.
  • the entire electrode can be easily made into a liquid phase and bonded to the element body.
  • the entire electrode since the entire electrode is in a liquid phase, it is difficult for the electrode to be peeled from the element body, and conductivity can be ensured.
  • a cylindrical element body (size: diameter 20 mm ⁇ thickness 10 mm) made of a sintered body of magnesium silicide (Mg 2 Si) (porosity 2 vol%) was prepared.
  • both sides of the element body are filled with powder of the material shown in Table 1 and subjected to current sintering by the method described above.
  • a constant thickness electrode was formed.
  • the porosity of the electrode is shown in Table 1. Except for Example 5, a plurality of copper silicide powders having different Si / Cu ratios were mixed to obtain the ratio shown in Table 1, and in Example 5, a single composition having the Si / Cu ratio shown in Table 1 Copper silicide powder was used.
  • thermoelectric conversion elements of Examples and Comparative Examples the electrical resistance value, the presence or absence of cracks during production, and the Si / Cu ratio of the electrodes were evaluated as follows.
  • thermoelectric conversion element A 10 mm ⁇ 10 mm ⁇ 10 mm cubic sample 10 was cut out from the obtained thermoelectric conversion element and used for evaluation.
  • the circuit shown in FIG. 4 is assembled using a DC power source and a multimeter, and a constant current of 50 mA is passed between both electrodes 15, and one electrode 15 is digitally moved from 1 mm to 9 mm at 1 mm intervals. Each voltage was measured by bringing the electrode E of the multimeter into contact with the side surface of the element body 11. Next, the resistance value was obtained from the relationship between the voltage and the current, linearly approximated from the graph of the distance from the electrode end and the resistance value, and the intercept was defined as the electric resistance.
  • thermoelectric conversion element The presence or absence of cracks during production was determined by visually observing the thermoelectric conversion element when it was taken out from the electric sintering apparatus after it was subjected to current sintering to form an electrode, or after being cut into a thermoelectric conversion element size. It was confirmed.
  • Si / Cu ratio of electrode Regarding the Si / Cu ratio of the electrode, the Cu amount and the Si amount on the surface of the thermoelectric conversion element (surface on which the electrode is formed) are measured with EPMA (JXA-8800RL manufactured by JEOL Ltd.), and the Si / Cu ratio is determined. Asked. Specifically, the electrode surface of the cubic sample was polished, and the Cu value and the Si amount were measured with EPMA at any five locations on the electrode surface to obtain an average value. In the case where the measurement point is a cavity or the end of the particle, the center of the particle closest to the measurement point was measured.
  • EPMA JXA-8800RL manufactured by JEOL Ltd.
  • Comparative Example 1 in which the electrode was made of nickel silicide, cracking occurred during manufacture. For this reason, the electrical resistance value and the porosity of the electrode were not evaluated.
  • Comparative Example 2 in which the electrode was made of nickel, cracks occurred during production. For this reason, the electrical resistance value and the porosity of the electrode were not evaluated.
  • Comparative Example 3 in which the electrode was made of aluminum, cracks did not occur during manufacture, but the electrical resistance value was as high as 0.19 ⁇ .
  • Example 1 to 11 in which the electrodes were made of copper silicide, cracks did not occur during manufacture, and the electrical resistance value was low. From the above, according to Examples 1 to 11, the element body made of the thermoelectric conversion material of the silicide-based compound and the electrode are securely bonded, the electric resistance at the interface is sufficiently low, and the element body and the electrode are connected to each other. It was confirmed that a thermoelectric conversion element capable of suppressing the occurrence of cracking can be provided. In Example 11 in which the porosity exceeded 60%, although lower than that in Comparative Example 3, the electrical resistance value was slightly higher than those in Examples 1 to 10.
  • thermoelectric conversion element of the present invention the element body made of the thermoelectric conversion material of the silicide compound and the electrode are reliably bonded, the electrical resistance at the interface is sufficiently low, and the element body and the electrode are cracked. Therefore, industrial use is possible.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Structural Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Powder Metallurgy (AREA)
  • Ceramic Products (AREA)
  • Silicon Compounds (AREA)

Abstract

L'invention concerne un élément de conversion thermoélectrique comprenant : un corps d'élément (11) qui comprend un matériau de conversion thermoélectrique qui est constitué de composés de siliciure ; et des électrodes (15) formées respectivement sur une surface du corps d'élément (11) et l'autre surface qui est sur le côté arrière de la surface. Les électrodes (15) sont formées d'un corps fritté de siliciure de cuivre, et les électrodes (15) et le corps d'élément (11) sont directement reliés.
PCT/JP2019/010818 2018-03-16 2019-03-15 Élément de conversion thermoélectrique WO2019177147A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US16/957,968 US11152554B2 (en) 2018-03-16 2019-03-15 Thermoelectric conversion element
KR1020207019226A KR20200130806A (ko) 2018-03-16 2019-03-15 열전 변환 소자
CN201980007644.4A CN111630672A (zh) 2018-03-16 2019-03-15 热电转换元件
EP19768346.9A EP3767689A4 (fr) 2018-03-16 2019-03-15 Élément de conversion thermoélectrique

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2018-049874 2018-03-16
JP2018049874 2018-03-16
JP2019-040845 2019-03-06
JP2019040845A JP7242999B2 (ja) 2018-03-16 2019-03-06 熱電変換素子

Publications (1)

Publication Number Publication Date
WO2019177147A1 true WO2019177147A1 (fr) 2019-09-19

Family

ID=67907801

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2019/010818 WO2019177147A1 (fr) 2018-03-16 2019-03-15 Élément de conversion thermoélectrique

Country Status (1)

Country Link
WO (1) WO2019177147A1 (fr)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07202274A (ja) 1993-12-28 1995-08-04 Nissan Motor Co Ltd 熱電装置およびその製造方法
JP2003234516A (ja) * 2002-02-12 2003-08-22 Komatsu Ltd 熱電モジュール
JP2006339283A (ja) * 2005-05-31 2006-12-14 Toyota Motor Corp 熱電モジュール
WO2012073946A1 (fr) 2010-11-30 2012-06-07 学校法人東京理科大学 Elément et module de conversion thermoélectrique
JP2013201382A (ja) * 2012-03-26 2013-10-03 Nagoya Univ 熱電変換モジュール及びその製造方法
JP2018049874A (ja) 2016-09-20 2018-03-29 富士通株式会社 半導体装置及びその半導体装置の製造方法
JP2019040845A (ja) 2017-08-29 2019-03-14 Ｔｏｙｏ Ｔｉｒｅ株式会社 二次電池の状態予測方法、充電制御方法、システム、及びプログラム

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07202274A (ja) 1993-12-28 1995-08-04 Nissan Motor Co Ltd 熱電装置およびその製造方法
JP2003234516A (ja) * 2002-02-12 2003-08-22 Komatsu Ltd 熱電モジュール
JP2006339283A (ja) * 2005-05-31 2006-12-14 Toyota Motor Corp 熱電モジュール
WO2012073946A1 (fr) 2010-11-30 2012-06-07 学校法人東京理科大学 Elément et module de conversion thermoélectrique
JP2013201382A (ja) * 2012-03-26 2013-10-03 Nagoya Univ 熱電変換モジュール及びその製造方法
JP2018049874A (ja) 2016-09-20 2018-03-29 富士通株式会社 半導体装置及びその半導体装置の製造方法
JP2019040845A (ja) 2017-08-29 2019-03-14 Ｔｏｙｏ Ｔｉｒｅ株式会社 二次電池の状態予測方法、充電制御方法、システム、及びプログラム

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3767689A4

Similar Documents

Publication Publication Date Title
JP7121230B2 (ja) マグネシウム系熱電変換材料の製造方法
US11647674B2 (en) Thermoelectric conversion material, thermoelectric conversion element, thermoelectric conversion module, and method for manufacturing thermoelectric conversion material
JP7242999B2 (ja) 熱電変換素子
EP3432371B1 (fr) Matériau de conversion thermoélectrique à base de magnésium, élément de conversion thermoélectrique à base de magnésium, dispositif de conversion thermoélectrique, et procédé pour fabriquer un matériau de conversion thermoélectrique à base de magnésium
JP4584034B2 (ja) 熱電モジュール
JP6317123B2 (ja) 熱電素子、熱電モジュールおよび熱電素子の製造方法
WO2019177147A1 (fr) Élément de conversion thermoélectrique
JP7121227B2 (ja) 熱電変換材料、及び、熱電変換材料の製造方法
WO2019163807A1 (fr) Matériau de conversion thermoélectrique, élément de conversion thermoélectrique et module de conversion thermoélectrique
KR102409289B1 (ko) 마그네슘계 열전 변환 재료, 마그네슘계 열전 변환 소자, 및 마그네슘계 열전 변환 재료의 제조 방법
JP7159854B2 (ja) 熱電変換材料、熱電変換素子、及び、熱電変換モジュール
JP7248157B2 (ja) 熱電変換材料、及び、熱電変換材料の製造方法
WO2022059593A1 (fr) Matériau de conversion thermoélectrique, élément de conversion thermoélectrique, élément peltier, module de conversion thermoélectrique et module peltier
WO2021132255A1 (fr) Matériau de conversion thermoélectrique, élément de conversion thermoélectrique et module de conversion thermoélectrique
JP2018157130A (ja) 熱電変換材料の製造方法
JP6549442B2 (ja) 熱電素子、熱電モジュールおよび熱電素子の製造方法
JP2022049670A (ja) 熱電変換材料、熱電変換素子、ペルチェ素子、および、熱電変換モジュール、ペルチェモジュール
JP2021103763A (ja) 熱電変換材料、熱電変換素子、および、熱電変換モジュール
JP2020150040A (ja) 熱電変換材料、熱電変換素子、及び、熱電変換モジュール
KR20190058221A (ko) 곡면형 열전소자의 제조방법

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19768346

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 2019768346

Country of ref document: EP