In掺杂Ag_(0.8)Pb_(18)SbTe_(20)热电材料的快速热压制备及性能表征

Rapid Hot Pressing of In-doped Ag_(0.8)Pb_(18)SbTe_(20) Thermoelectric Material and its Properties

研究了快速热压工艺和In掺杂对Ag0.8Pb18SbTe20基热电材料微结构和热电性能的影响。采用真空封管熔炼法成功制备n型Ag0.8Pb18InxSb1-xTe20(x=0.25,0.5,0.75,1)合金粉末材料,同时结合高能球磨使合金粉末粒度达到微米量级。利用快速热压烧结工艺,在693 K温度、15 MPa压力下烧结30 min,制备块体热电材料。研究结果表明,In对Sb的取代增加了热电材料的电导率,改善了材料的热电性能。当In掺杂量x=1时,材料于623 K的电导率达到最大值239 S/cm;当x=0.5时,材料于623 K的功率因子达到最大值3.1×10-3W/(m.K2)。

The influences of rapid hot pressing and In doping on the microstructure and thermoelectric properties of Ag0.8Pb18SbTe20 were investigated.The n-type Ag0.8Pb18InxSb1-xTe20（x=0.25,0.5,0.75,1） powder alloy is prepared successfully by vacuum sealed melting,and the powder particle size can reach a micron level by high energy ball milling.Rapid hot-pressing sintering was adopted to prepare lumpy thermoelectric material at 693 K and 15 MPa for 30 min.The results show that the substitution of In for Sb enhances the conductivity of the thermoelectric material and thus improves its thermoelectric properties.The max.electrical conductivity at 623 K is up to 239 S/cm when the In dosage x is equal to 1.And the power factor reaches a maximum of 3.1×10-3 W/（m·K2） at the same temperature but with x equal to 0.5.