电场激活压力辅助烧结对(Bi2Te3)0.2(Sb2Te3)0.8热电材料微观结构及热电性能的影响

采用电场激活压力辅助烧结（FAPAS）技术制备了(Bi2Te3)0.2(Sb2Te3)0.8热电材料，采用无电场、低电场强度和高电场强度三种烧结方式作为对比实验，研究了烧结过程中施加电场强度对(Bi2Te3)0.2(Sb2Te3)0.8热电材料微观结构和热电性能的影响。研究结果表明，在烧结过程中施加电场，可明显提高(Bi2Te3)0.2(Sb2Te3)0.8热电材料的电导率和Seebeck系数，从而提高其综合电功率因子；而采用大电场强度烧结则会使(Bi2Te3)0.2(Sb2Te3)0.8材料出现层状结构择优取向，在电性能相对较高的情况下亦使其热导率明显减低，从而获得较高ZT值。

Effect of current on the microstructure and performance of (Bi2Te3)0.2(Sb2Te3)0.8 thermoelectric material via field activated and pressure assisted sintering

(Bi2Te3)0.2(Sb2Te3)0.8 thermoelectric material was sintered via field activated and pressure assisted sintering (FAPAS) process. By applying different current intensity (0, 60,320 A/cm²) in the sintering process, the effects of electric current on the microstructure and thermoelectric performance were investigated. It demonstrated that the applying of electric current in the sintering process could significantly improve the uniformity and density of (Bi2Te3)0.2(Sb2Te3)0.8 samples. When the current intensity was raised to 320 A/cm², preferred orientation of grains was observed. Moreover, positive effects on the thermoelectric performance of applying electric current in the sintering process were also confirmed. Increase of 0.02 and 0.11 in the maximum figure of merit ZT value could be acquired by applying current of 60 and 320 A/cm², respectively.