US 11,957,052 B2
Thermoelectric material, manufacturing method of thermoelectric material, thermoelectric conversion element, and thermoelectric conversion module
Shinichi Yamamoto, Fujisawa (JP); Masami Okamura, Yokohama (JP); Nobuaki Nakashima, Yokohama (JP); and Masanori Mizobe, Yokohama (JP)
Assigned to Kabushiki Kaisha Toshiba, Tokyo (JP); and Toshiba Materials Co., Ltd., Yokohama (JP)
Filed by KABUSHIKI KAISHA TOSHIBA, Tokyo (JP); and TOSHIBA MATERIALS CO., LTD., Yokohama (JP)
Filed on Jan. 24, 2019, as Appl. No. 16/256,276.
Application 16/256,276 is a continuation of application No. PCT/JP2017/027476, filed on Jul. 28, 2017.
Claims priority of application No. 2016-148104 (JP), filed on Jul. 28, 2016.
Prior Publication US 2020/0028059 A1, Jan. 23, 2020
Int. Cl. H10N 10/01 (2023.01); B22F 3/15 (2006.01); B22F 3/24 (2006.01); B22F 9/04 (2006.01); C22C 12/00 (2006.01); C22C 30/04 (2006.01); H10N 10/853 (2023.01)
CPC H10N 10/01 (2023.02) [B22F 3/15 (2013.01); B22F 3/24 (2013.01); B22F 9/04 (2013.01); C22C 12/00 (2013.01); C22C 30/04 (2013.01); H10N 10/853 (2023.02)] 18 Claims
OG exemplary drawing
 
17. A thermoelectric material comprising:
a sintered body formed of at least one of (1) a p-type thermoelectric material represented by a composition formula (1) and having a MgAgAs type crystal structure as a main phase, and (2) an n-type thermoelectric material represented by the composition formula (1) and having a MgAgAs type crystal structure as a main phase, the sintered body having a relative density of 98.0% or more,
(Tia1Zrb1Hfc1)xαyβ100-x-y,  (1)
wherein, in the composition formula (1), 0<a1≤1, 0<b1≤1, 0<c1≤1, a1+b1+c1=1, 30≤x≤35, and 30≤y≤35,
wherein an area ratio of internal defects by ultrasonic flaw detection in a thickness direction with respect to a surface parallel with one plane of the thermoelectric material is in a range of 2.9% to 10%, and a maximum length of appearance defects present at each vertex of a chip of the thermoelectric material is from 47 μm to 412 μm,
wherein the chip has a cube shape or a rectangular parallelepiped shape,
wherein the cubic or rectangular parallelepiped chip has a length in a range of 2 to 10 mm, a width in a range of 2 to 10 mm, and a height in a range of 2 to 20 mm,
wherein, in the n-type thermoelectric material, α is Ni, β is Sn, and 30 atomic % or less of β is substituted by at least one element selected from the group consisting of Si, Mg, As, Sb, Bi, Ge, Pb, Ga, and In,
wherein, in the p-type thermoelectric material, α is Co, β is Sb, and 30 atomic % or less of β is substituted by at least one element selected from the group consisting of Sn, Si, Mg, As, Bi, Ge, Pb, Ga, and In, and
wherein the thermoelectric material is processed into the shape of the chip through cutting.