不同温度烧结的赝两元合金(PbTe)1-x(snTe)x电学性能

首次采用粉末冶金法在大成分范围内制备了赝两元合金(PbTe)_1-x(SnTe)_x(x=0～1),并对其电学性能进行了系统地研究.实验发现:经550℃烧结后,随合金中SnTe摩尔分数x增大,合金的最大Seebeck系数值减小.当摩尔分数x≤0.6时,最大Seebeck系数所对应的温度逐渐升高;摩尔分数x>0.6时基本不变.当摩尔分数x=0.6时电导率达最大值.经高温烧结后两参数值也有类似的变化规律,但摩尔分数>0.2的各合金Seebeck系数值高于550℃烧结后的合金,电导率降低.从而得出:烧结温度对赝两元合金(PbTe)_1-x(SnTe)_x的综合电学性能影响不大.

Electrical Properties of Pseudo-binary Alloys (PbTe)1-x(SnTe)x Sintered at Different Temperatures

Pseudo-binary alloys (PbTe)_1-x(SnTe)_x (x=0～1) were firstly prepared by the powder metallurgy method and their electrical properties were experimentally investigated. The results show that the grain size and pore size of the alloys sintered at higher temperature are larger than those sintered at lower one. The maximum Seebeck coefficients decrease with mole fraction x increasing, whereas the temperature, corresponding to the maximum Seebeck coefficients, shifts to higher temperature side when x ranges from 0 to 0.6, and remains almost unchanged when x>0.6. The electrical conductivity reaches the maximum when mole fraction x equals to 0.6. Besides, both Seebeck coefficients and electrical conductivities for all of the alloys sintered at high temperature reveal similar variation with the temperature to those sintered at lower one, not only the Seebeck coefficients but also the electrical resistivities for the alloys sintered at 550℃, however, are lower than those for the alloys with the same mole fraction but sintered at 725℃ when x≥0.2. It can be concluded, therefore, that the resultant electrical properties are little influenced by sintering temperature for the pseudo-binary alloys (PbTe)_1-x(SnTe)_x.