公开(公告)号：US4447277A

公开(公告)日：1984-05-08

申请号：US412306

申请日：1982-08-27

申请人： Tumkur S. Jayadev ,  On V. Nugyen

发明人： Tumkur S. Jayadev ,  On V. Nugyen

IPC分类号： H01L35/16 ,  H01L35/18 ,  C22C28/00

CPC分类号： H01L35/16 ,  H01L35/18

摘要： There is disclosed new and improved multiphase thermoelectric alloys and a method for making the same. The alloys are disordered materials having a multiplicity of matrix crystallites separated by generally disordered grain boundaries containing transitional phases and grain boundary regions of various phases including electrically conductive phases having at least one phase having high electrical conductivity.The alloys are formed from a mixture of at least two separately prepared multiple element compounds preferably a first compound Bi.sub.10 Sb.sub.30 Te.sub.60 or Bi.sub.40 Te.sub.48 Se.sub.12 and a second compound Ag.sub.25 Sb.sub.25 Te.sub.50. These compounds while crystalline, have different crystalline structures. They themselves are polycrystalline and do not represent the most stable crystalline structure. The first compound has a rhombohedral crystalline structure and the second compound has a face centered cubic crystalline structure. The compounds are combined in solid particulate form in proportions of 97 to 99.25 percent Bi.sub.10 Sb.sub.30 Te.sub.60 and 3 to 0.25 percent Ag.sub.25 Sb.sub.25 Te.sub.50 or 99 percent Bi.sub.40 Te.sub.48 Se.sub.12 to 1 percent Ag.sub.25 Sb.sub.25 Te.sub.50. The mixture is then heated in a quartz tube to an elevated temperature and then drawn through a temperature gradient for cooling.The alloys include in the grain boundary regions various phases of silver and tellurium. The silver containing phases establish low resistance current paths through the crystallites to provide the alloy with high electrical conductivity. The disorder of the grain boundaries and the non-highly electrical conductive phases of the grain boundary regions provide low thermal conductivity desired for thermoelectric applications.Also disclosed are alloys doped with a dopant such as tellurium iodide to form thermoelectric alloys having maximized S.sup.2 .sigma. products.

摘要翻译： 公开了新的和改进的多相热电合金及其制造方法。 合金是具有多个基体微晶的无序材料，其中包含过渡相和通常包含具有至少一个具有高电导率的相的导电相的各个相的晶界区域的无序晶界分离。 合金由至少两种单独制备的多元素化合物，优选第一化合物Bi10Sb30Te60或Bi40Te48Se12和第二化合物Ag25Sb25Te50的混合物形成。 这些化合物同时结晶，具有不同的晶体结构。 它们本身是多晶的，并不代表最稳定的晶体结构。 第一种化合物具有菱形结晶结构，第二种化合物具有面心立方晶体结构。 化合物以97至99.25％Bi10Sb30Te60和3至0.25％Ag25Sb25Te50或99％Bi40Te48Se12至1％Ag25Sb25Te50的比例以固体颗粒形式组合。 然后将混合物在石英管中加热至升高的温度，然后通过温度梯度进行冷却。 该合金在晶界区域包括银和碲的各个相。 含银相通过微晶建立低电阻电流路径，为合金提供高导电性。 晶界的晶界和非高导电相的紊乱提供热电应用所需的低热导率。 还公开了掺杂有掺杂剂如碘化碲的合金，以形成具有最大化S2西格玛产品的热电合金。