【摘要】 通过对两元 p-型梯度热电材料 Fe Si2 / Bi2 Te3界面温度的建模计算与实验验证 ,在固定热冷端温区内积分得出的 Z- ΔT值与界面温度 Ti 的关系曲线为 :Z- ΔT =0 .6 72 +11.7× 10 - 4Ti - 1.31× 10 - 6 T2i - 3.4 9× 10 - 9T3i该关系可用来表征两元梯度结构的热电性能。从拟合曲线上得出该梯度结构的最佳界面温度为 2 2 0℃～ 2 30℃ ,这与实验测出两单段材料 (Fe Si2 ,Bi2 Te3)长度比为 10∶ 1左右时所形成的界面温度较为接近。通过测试不同长度比的材料输出功率 ,也发现 10∶ 1梯度材料的最大输出功率较大 ,是相同温差下单段 β- Fe Si2 材料的 2倍～ 2 .6倍。更多还原

【Abstract】 The optimum interface temperature of the p type graded FeSi 2/Bi 2Te 3 thermoelectric material has been simulated and experimentally measured. Based on the model, the integrated figure of merit, Z- Δ T , over a temperature range can be described as a function of the interface temperature T i with the form of :Z- Δ Τ=0 672+11 7×10 -4 T i -1 31×10 -6 T 2 i -3 49×10 -9 T 3 i The interface temperature of 220℃ 230℃ obtained by the model corresponds well to that experimentally measured values when the segment length ratio of two monolithic materials keeps 10∶1. It was found that the maximal output power could be obtained for the p type graded FeSi 2/Bi 2Te 3 thermoelectric material when the length ratio of FeSi 2:Bi 2Te 3 being 10:1, to be 2～2 6 times as large as the monolithic β FeSi 2 material at the same temperature.更多还原