P-type thermoelectric conversion material, thermoelectric conversion module, and method of manufacturing p-type thermoelectric conversion material

A thermoelectric conversion module comprising:

• a plurality of thermoelectric conversion elements;
• and
• an electrode which electrically connects the thermoelectric conversion elements to each other,
• wherein the thermoelectric conversion elements include a p-type thermoelectric conversion element including a p-type thermoelectric conversion material having a full Heusler alloy having a composition represented by the following General Formula (1) and having a relative density of 85% or more and an n-type thermoelectric conversion element connected to the p-type thermoelectric conversion element by the electrode,
• FexTiyMAaMBb (1)
• in Formula (1), MA is one element selected from the group consisting of Si, Sn, and Ge, MB is one element selected from the group consisting of Al, Ga, and In, and x, y, a, and b are numbers set so that x+y+a+b=100, a+b=z, 50<x≤52.5, 20≤y≤24.5, 24.5≤z≤29, a>0, and b>0 in atom %, respectively.

A method of manufacturing a p-type thermoelectric conversion material, comprising:

• preparing Fe raw material powders, Ti raw material powders, MA raw material powders, and MB raw material powders in a ratio depending on a target composition;
• mixing the Fe raw material powders, the Ti raw material powders, the MA raw material powders, and the MB raw material powders with one another to prepare a mixture containing Fe, Ti, MA, and MB, and amorphizing the mixture to form an amorphized alloy;
• and
• heating the amorphized alloy to manufacture the p-type thermoelectric conversion material having a full Heusler alloy having a composition represented by the following General Formula (1) and having a relative density of 85% or more,
• FexTiyMAaMBb (1)
• wherein in Formula (1), MA is one element selected from the group consisting of Si, Sn, and Ge, MB is one element selected from the group consisting of Al, Ga, and In, and x, y, a, and b are numbers set so that x+y+a+b=100, a+b=z, 50<x≤52.5, 20≤y≤24.5, 24.5≤z≤29, a>0, and b>0 in atom %, respectively.