空间核电源用热电材料与器件的高温环境中子辐照效应研究

SiGe和Half-Heusler热电器件在空间核电源中工作时，将受到温差与同位素热源或反应堆中子辐照的同步作用。中子辐照将在器件中引入缺陷而导致器件性能降低。不同温度条件下SiGe热电材料和Half-Heusler热电材料的中子辐照效应仍未知。目前也没有SiGe和Half-Heusler热电器件的中子辐照研究。本项目拟开展SiGe和Half-Heusler热电材料、热电材料/电极连接界面、以及SiGe和Half-Heusler热电器件在不同温度下的中子辐照效应研究。揭示高温和中子同时作用下，中子辐照对SiGe和Half-Heusler热电材料、热电材料/电极连接界面的微观组织结构、输运特性和界面性能的影响及机理。考察辐照后热电器件的性能衰减率及原因。研制抗辐照分段式热电材料。

SiGe thermoelectric module and Half-Heusler thermoelectric module will be exposed to neutron irradiation combined with temperature gradient over a long period of time in space missions in radioisotope thermoelectric generators or space reactor power system. The neutron irradiation at certain doses will introduce defects and result in properties degradation of the modules. The effects of neutron irradiation on SiGe and Half-Heusler thermoelectric materials at elevated temperature are unknown. And there is no neutron irradiation studies investigating the changes on SiGe thermoelectric module and Half-Heusler thermoelectric modules. In this project, we will investigate effects of nentron irradiation on SiGe and Half-Heusler thermoelectric materials and modules at different temperatures. The evolution of micro-structure and properties for SiGe and Half-Heusler thermoelectric materials, SiGe/electrode joints and Half-Heusler/electrode joints will be studied. The degradation of properties for thermoelectric modules will be calculated and measured. The mechanism of neutron irradiation damage in SiGe and Half-Heusler thermoelectric materials and modules will be recovered. We will also develop segement thermoelectric materials with high irradiation resistance.