MNiSn基half-Heusler合金微波固相合成机理及其热电性能研究

项目名称： MNiSn基half-Heusler合金微波固相合成机理及其热电性能研究

项目编号： No.51304005

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 矿业工程

项目作者： 雷鹰

作者单位： 安徽工业大学

项目金额： 25万元

中文摘要： 开展热电材料基础研究对我国应对能源和环境危机具有极其重要的现实意义。针对中温热电材料MNiSn(M=Ti,Zr,Hf)基HH合金制备工艺复杂、成本昂贵、热电性能优化困难等问题，本项目拟以Ti、Zr、Hf、Ni、Sn等金属粉为原料，建立微波固相合成-热压烧结制备MNiSn基HH热电合金新方法。在阐述金属与微波作用规律基础上，采用微波合成与电弧熔炼对比，探索原料配比、微波功率、辐射时间等影响因素对产物相组成、杂质分布、晶格参数、晶粒大小等微观结构特征的影响规律,揭示微波强化离子扩散、促进相组成均匀化、促使原位析出纳米晶体结构的合成机理，阐明产物塞贝克系数、电导率、热导率等热、电传输性能与微观结构特征之间的内在关系, 进行热电性能调控研究，建立微波固相合成-热压烧结制备高热电优值HH合金的调控机制。项目的开展对丰富微波化学科学内涵，推动微波在热电材料领域的技术发展具有重要的学术价值和科学意义。

中文关键词： 半赫斯勒合金；微波加热；微观结构；晶格热导率；热电优值

英文摘要： The development of basic research of thermoelectric material synthesis holds greater realistic significance for us to respond to energy crisis and environmental challenges. Aiming to solve the problems of e.g. complicated and costly preparation route, difficulties in optimization of the thermal and electrical transport performances of the promising intermediate temperate thermoelectric material of MNiSn(M=Ti, Zr, Hf) based half-Heusler (HH) alloys, this project tries to establish microwave-hot pressing new route with Ti, Zr, Hf, Ni, Sn, etc. metal powders as raw materials and microwave heating as synthesis approach. Based on the investigations on the interaction of metal powders and microwave, the comparison of microwave synthesis and arc smelting methods were investigated. The effects of influencing factors such as stoichiometric ratio, microwave power and irradiation time on microstructure characteristics such as phase compositions, element distributions, lattice parameters, and grain size will be investigated. Then the microwave solid-phase synthesis mechanisms i.e. promotion of ions diffusion, homogenization of phase, and in-situ precipitation of nano crystalline structure will be revealed. The thermal and electrical transport properties such as seeback coefficient, electric conductivity, thermal conductivit

英文关键词： half-Heusler alloys；microwave heating；microstructure；lattice thermal conductivity；thermoelectric figure of merit