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采用直流4电极法探索P型Bi0.4Sb1.6Te3+5％的Te合金的熔体结构转变温度范围,在此基础上,采用不同熔体处理工艺得到母合金,随后采用球磨、SPS烧结技术制备块体材料.结果表明,经历熔体结构转变后,烧结试样的电导率有明显提升,而Seebeck系数略有降低,故其功率因子增加.由于熔体结构转变试样具有更多的晶界以及晶体结构缺陷,增强声子的散射,使合金的热导率显著降低.因此经历熔体结构转变的试样具有更优的热电性能,且在120℃时ZT(热电材料性能参数)值最大,为1.17.“,”The temperature range of liquid structural transition (LST) for P-type Bi0.4Sb1.6Te3+5％ Te alloy was explored by the direct current four-probe method.And then,the parent ingots with different melt states were prepared,respectively,which were subjected to ball milling followed by SPS sintering technology to prepare bulky materials.It is found that the electrical conductivity of the sintered samples after LST is superior significantly to that of the ones without structural transition,while the Seebeck coefficient is decreased slightly,therefore the power factor of the sintered samples is increased slightly.Meanwhile,the induced crystal structure defects in the sample after LST can lead to a strongly scattering of the phonons and thus the thermal conductivity is suppressed significantly.As a result,the sample after LST has the better thermoelectric properties,and the highest ZT value of 1.17 is presented at 120℃.