Patent ID: 11957052
Assignee: TOSHIBA MATERIALS CO., LTD.
Field: Materials, metallurgy (Chemistry)
Classification: CPC H  B  C | IPC B  C  H

Claim 17:
18. A thermoelectric material comprising:
a plurality of chips of a sintered body processed into a shape of the chip through cutting, the sintered body being 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) a n-type thermoelectric material represented by the composition formula (1) and having a MgAgAs type crystal structure as a main phase, the plurality of chips having a relative density with an average value of 99.0% or more and a standard deviation of 0.5% or less,

(Tia1Zrb1Hfc1)xαyβ100-x-y,  (1)

wherein 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 each of the chips is in a range of 2.9% to 10%, and no defect having a length of 520 μm or more is present in a surface of each of the chips, each of the chips having 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, and
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.