초록 ▼

A method includes preparing a thermoelectric material including p-type or n-type material and first and second caps including transition metal(s). A powder precursor of the first cap can be loaded into a sintering die, punches assembled thereto, and a pre-load applied to form a first pre-pressed str

A method includes preparing a thermoelectric material including p-type or n-type material and first and second caps including transition metal(s). A powder precursor of the first cap can be loaded into a sintering die, punches assembled thereto, and a pre-load applied to form a first pre-pressed structure including a first flat surface. A punch can be removed, a powder precursor of the p-type or n-type material loaded onto that surface, the punch assembled to the die, and a second pre-load applied to form a second pre-pressed structure including a second substantially flat surface. The punch can be removed, a powder precursor of the second cap loaded onto that surface, the first punch assembled to the die, and a third pre-load applied to form a third pre-pressed structure. The third pre-pressed structure can be sintered to form the thermoelectric material; the first or second cap can be coupled to an electrical connector.

대표청구항 ▼

1. A thermoelectric device including: a thermoelectric material including a p-type or n-type material and first and second caps respectively including first and second cap materials respectively disposed on either side of the p-type or n-type material, the first and second cap materials each respect

1. A thermoelectric device including: a thermoelectric material including a p-type or n-type material and first and second caps respectively including first and second cap materials respectively disposed on either side of the p-type or n-type material, the first and second cap materials each respectively including an independently selected transition metal,the thermoelectric material being formed by co-sintering a powder precursor of the first cap material, a powder precursor of the p-type or n-type material, and a powder precursor of the second cap material in a sintering die,wherein a particle size ratio of the powder precursor of the p-type or n-type material to the powder precursors of the first and second cap materials is in the range of approximately 1:1 to approximately 1:50; andan electrical connector, at least one of the first and second caps of the thermoelectric material being coupled to the electrical connector. 2. The device of claim 1, wherein the first and second cap materials respectively include a coefficient of thermal expansion (CTE) that differs by 20% or less from a CTE of the p-type or n-type material. 3. The device of claim 1, wherein the first and second cap materials respectively include a coefficient of thermal expansion (CTE) that differs by 10% or less from a CTE of the p-type or n-type material. 4. The device of claim 3, wherein the first and second cap materials independently include one or more materials selected from the group consisting of Kovar, Cr, molybdenum, Ni—Fe alloy, and Cu—Mo alloy. 5. The device of claim 3, wherein the first and second cap materials independently include one or more materials selected from the group consisting of Kovar, Cr, molybdenum, and 50/50 Ni—Fe alloy. 6. The device of claim 5, wherein the CTE of the p-type or n-type material is approximately 6-8 ppm/° C. 7. The device of claim 3, wherein the first and second cap materials respectively independently include one or more materials selected from the group consisting of Ni, Monel, Dura Nickel, a Cu—Ni alloy, a Cu—Mo alloy, and Fe. 8. The device of claim 3, wherein the first and second cap materials respectively independently include one or more materials selected from the group consisting of Ni, Monel, Dura Nickel, Cu—Ni 30, and Cu—Ni 10. 9. The device of claim 8, wherein the CTE of the p-type or n-type material is approximately 13-17 ppm/° C. 10. The device of claim 1, wherein neither of the first and second cap materials includes a silicide. 11. The device of claim 1, including a plurality of individual thermoelectric legs respectively formed by dicing the thermoelectric material. 12. The device of claim 11, wherein at least one of first and second caps of each of four of the individual thermoelectric legs is coupled to the electrical connector. 13. The device of claim 11, wherein: a cross-sectional area of each of the individual thermoelectric legs is in the range of approximately 1.8 mm×1.8 mm and approximately 3.6 mm×1.8 mm;a thickness of the p-type or n-type material is in the range of approximately 0.5 mm to approximately 2.5 mm; andan electrical resistance of each of the individual thermoelectric legs is in the range of approximately 2 mOhm to approximately 10 mOhm. 14. The device of claim 1, wherein the p-type or n-type material includes magnesium silicide or manganese silicide. 15. The device of claim 14, wherein the powder precursor of the p-type or n-type material includes Mg2Si ultrafine powder formed based on Si and Mg elemental materials, and wherein the powder precursors of the first and second cap materials include a metallic powder. 16. The device of claim 15, the Mg2Si ultrafine powder being characterized by an average particle size of about 10 nm to about 1 μm. 17. The device of claim 15, the Mg2Si ultrafine powder being characterized by an average particle size of about 100 nm. 18. The device of claim 17, wherein the Mg2Si ultrafine powder is formed and handled in an argon environment with oxygen concentration under 200 ppm before the sintering. 19. The device of claim 15, wherein the Mg2Si ultrafine powder is formed based on the Si and Mg elemental materials using a mechanical alloying ball mill process. 20. The device of claim 15, wherein the metallic powder includes nickel powder. 21. The device of claim 20, the nickel powder being characterized by an average particle size of about 100 nm to about 10 μm. 22. The device of claim 20, the nickel powder being characterized by an average particle size of about 5 μm or less. 23. The device of claim 15, wherein a particle size ratio of the Mg2Si ultrafine powder to the metallic powder is approximately 1:20. 24. The device of claim 14, wherein the powder precursor of the p-type or n-type material includes MnSix ultrafine powder formed based on Si and Mn elemental materials, and wherein the powder precursors of the first and second cap materials include a metallic powder. 25. The device of claim 24, the MnSix ultrafine powder being characterized by an average particle size of about 44 μm or smaller. 26. The device of claim 24, wherein the MnSix ultrafine powder is formed and handled in an argon environment before the sintering. 27. The device of claim 24, wherein the MnSix ultrafine powder is formed based on the Si and Mn elemental materials using a ball mill process. 28. The device of claim 24, wherein the metallic powder includes chromium powder. 29. The device of claim 28, the chromium powder being characterized by an average particle size ranging from 100 nm to 150 μm in diameter. 30. The device of claim 28, the chromium powder being characterized by an average particle size ranging from 10 μm to 150 μm in diameter. 31. The device of claim 24, wherein a particle size ratio of the MnSix ultrafine powder to the metallic powder is in the range of approximately 4.4:1 to approximately 1:3.4. 32. The device of claim 24, wherein x is approximately 1.73. 33. The device of claim 1, wherein the p-type or n-type material includes tetrahedrite or Mg2SiSn. 34. The device of claim 1, wherein a particle size ratio of the powder precursor of the p-type or n-type material to the powder precursors of the first and second cap materials is in the range of approximately 4.4:1 to approximately 1:3.4. 35. The device of claim 1, wherein a particle size ratio of the powder precursor of the p-type or n-type material to the powder precursors of the first and second cap materials is in the range of approximately 1:20. 36. The device of claim 1, wherein a thickness of the thermoelectric material is approximately 0.5 mm to approximately 20 mm. 37. The device of claim 1, wherein a thickness of the thermoelectric material is approximately 2 mm to approximately 20 mm. 38. The device of claim 1, wherein a thickness of each of the first and second caps is approximately 0.2 mm to approximately 2 mm. 39. The device of claim 1, wherein a thickness of each of the first and second caps is approximately 1 mm to approximately 2 mm. 40. The device of claim 1, wherein a thickness of each of the first and second caps is greater than approximately 2 mm. 41. The device of claim 1, wherein the co-sintering includes: loading a powder precursor of the first cap material into a sintering die;assembling one or more punches to the powder precursor of the first cap material in the sintering die;applying a first pre-load via the one or more punches to the powder precursor of the first cap material to form a first pre-pressed structure including a first substantially flat surface;removing a first punch of the one or more punches to expose the first substantially flat surface;loading a powder precursor of the p-type or n-type material into the sintering die and onto the exposed first substantially flat surface;assembling the first punch to the powder precursor of the p-type or n-type material in the sintering die;applying a second pre-load via the one or more punches to the first pre-pressed structure and the powder precursor of the p-type or n-type material to form a second pre-pressed structure including a second substantially flat surface;removing the first punch to expose the second substantially flat surface;loading a powder precursor of the second cap material into the sintering die and onto the exposed second substantially flat surface;assembling the first punch to the powder precursor of the second cap material in the sintering die;applying a third pre-load via the one or more punches to the second pre-pressed structure and the powder precursor of the second cap to form a third pre-pressed structure; andsintering the third pre-pressed structure to form the thermoelectric material.