| 摘要 |
1,154,579. Thermoelectric materials. COMMISSARIAT A L'ENERGIE ATOMIQUE. 13 July, 1966 [13 July, 1965], No. 31551/66. Heading H1K. [Also in Division C7] Germanium-silicon alloys for use in thermoelectric conversion of energy are prepared by melting a mixture of Ge and Si powders together in this presence of a solvent metal at a temperature of not more than 1450‹ C., keeping the melt at this temperature for sufficient time to ensure homogenization and then cooling it to co-precipitate the Ge and Si and to allow crystals to grow followed by further cooling to ambient temperatures and separation of the crystals and solvent metal. Solvent metals mentioned are As, Sb, Ga, In, Bi, Sn, Pb, Tl, Ag, Au, Zn, Cd and Al. Traces of the solvent metal remaining in the alloy act as dopants and determine its conductivity type. The melting may be carried out under pressure if the solvent metal is too volatile. The solvent metal may be removed by vacuum or chemical treatment or by filtration of the solid crystals from the molten solvent metal. The final alloy may be heated to its solidus temperature in an atmosphere of SiCl 4 and GeCl 4 to obtain slugs of suitable size for thermoelectric use. The melting may preferably be carried out in a crucible of vitreous carbon, beryllia or zinc silicate. |
