【摘要】 Bi2Te3基半导体材料是目前室温下性能最好的热电材料,经过几十年的研究,块体Bi2Te3基材料的最高热电优值ZT一直徘徊在1左右。机械合金化是一种制备粉末材料的常用方法,能够将原始粉末通过球磨直接合成合金粉末,制备出熔炼法无法合成的材料,具有低成本的优势。采用机械合金化方法制备Bi2Te3系合金粉末,对其进行掺杂来提高性能,再在气氛保护下进行烧结,并系统研究各因素对材料热电性能的影响。当机械球磨在20h以上,在520℃温度下可以得到较好热电性能的块材。更多还原

【Abstract】 Thermoelectric materials interconvert theat and electricity direetly.They are used in Power generation and cooling.Bi2Te3-based materials are the best thermoelectric material at room temperature at present.The figure of merit ZT of Bi2Te3 is about unit for decades.Mechanical alloying(MA) is a powerful method in the preparation of powders,which can directly alloy the raw materials into target powders in a relatively low cost way.In this work MA method is used to prepare Bi2Te3-based alloy powders,and doping is used to improve thermoelectric performance. Atmosphere protected sintering is used to consolide the powders into bulk material. Some exploring work of factors which impact the thermoelectric performance has been done.When MA time is more than 20 hours and sintering at 520℃ can attained the preferable thermoelectric performance.更多还原