Technova Corporation

Aisin Seiki Kabushiki Kaisha

National Research Institute for Metals

Makoto Okabayashi

Takashi Amano

Masami Ishii

Toshiro Kawakami

Isao Nishida

Toshikuni Kusano

Juniti Mita

Shigeki Tokita

Naoki Kamiya

Shigeo Shinagawa

Thermoelectric device

A thermoelectric semiconductor material comprises Si crystal and crystal of metal silicide selected from the group consisting of Fe, Co, Cr, Mn and Ni. It is preferable that the metal silicide is .beta.-FeSi.sub.2. Moreover, the thermoelectric semiconductor material further contains at least one element selected from the group consisting of Vb, VIb, IIIb, VIII, VIIa and VIa in the atomic periodic table as an additive. This element can be used as a dopant. Furthermore, since both the phase of the Si crystal and the phase of the crystal of the metal silicide are changed to be an n-type or a p-type, a thermoelectric characteristics are improved.

Thermoelectric semiconductor material

A P-type thermoelectric material consists essentially of iron disilicide, metallic manganese and metallic aluminium dissolved in or alloyed with the iron disilicide, and silicon oxide and/or aluminum oxide present in the iron disilicide. The manganese is contained in an amount of from 1.67 to 4.1 atomic % with respect to a sum of atoms of iron and silicon constituting the iron disilicide, the metallic manganese and the metallic aluminum taken as 100 atomic %, and the metallic aluminum contained in an amount of from 1.33 to 3.33 atomic % with respect thereto, and a sum of the metallic manganese and the metallic aluminum in an amount of from 4.0 to 5.34 atomic % with respect thereto. The P-type thermoelectric material having such a composition produces a thermoelectromotive force equal to or greater than those of the conventional P-type thermoelectric materials comprised of iron disilicide, and it exhibits a mean resistivity equal to or smaller than that of the N-type thermoelectric material. Hence, a thermocouple including the P-type thermoelectric material and the N-type thermoelectric material can be remarkably enhanced in the performance as a whole.

P-type thermoelectric material

A process of joining galvanized steel sheets using a solder comprising copper and 10.about.30% by weight nickel with a welding machine. The process of joining the galvanized steel sheets includes a first step of phosphatizing before the joining.

Process of joining of a galvanized steel sheet

Welding between a rotor and shaft is accomplished by first placing the shaft within a movable holder of a pressure device. The rotor is then placed in the lower or stationary holder of the pressure device. Each holder is an electrode that can electrify the shaft and rotor. The stationary holder is a cup or container which has inside the cup, a low melting point alloy which conducts electricity from the lower electrode to the rotor to prevent concentration of electricity. Welding is finished by lowering the shaft onto the rotor which is in the cup which is heated to liquefy the low melting point alloy. As the shaft and rotor are pressed together, current is passed through each by the electrodes. The junction of the shaft and rotor are melted and thus joined. After cooling, any of the low melting point metal which remains on the rotor is removed by inserting the rotor in boiling water.

Method of welding between a rotor and a shaft and a device for the method

Growing community of inventors

Anjo, Japan

Makoto Okabayashi