%0 Journal Article
%T Effects of mechanical alloying process on thermoelectric properties of Bi2S3 Bulk<br>机械合金化过程对硫化铋块体热电性能的影响机理
%A Ge Zhen-Hu
%A Zhang Bo-Ping
%A Yu Zhao-Xin
%A Liu Yong
%A Li Jing-Feng
%A <br>葛振华
%A 张波萍
%A 于昭新
%A 刘勇
%A 李敬锋
%J 物理学报
%D 2012
%I 
%X Bismuth sulfide (Bi2S3) polycrystalline bulks are fabricated by spark plasma sintering (SPS) combined with a mechanical alloying (MA) process. The electrical transport properties are investigated with a special emphasis on dry-milling speed, wet-milling time and mediums in MA process. The phase structure, the microstructure, and the electrical/thermal transport properties for the bulk samples are measured. The results suggest that the second Bi2O3 phase is formed because of the micro-oxidation when the wet medium is fixed to absolute ethyl alcohol, which refines the grain sizes and affects electrical transport properties of the bulk samples. Prolonging the wet-milling time in absolute ethyl alcohol causes the increase of resistivity and the decrease of the power factor. The electrical transport properties degrade due to the porous microstructure in bulk samples even without oxidization as the acetone is used as a milling medium. The largest ZT value 0.25 is obtained at 573 K for the samples dry-milled under 425 r/min for 15 h without wet-milling, which is the highest value in the reported values so far.
%K mechanical alloying process
%K Bi2S3
%K thermoelectric
%K micro oxidation<br>机械合金化过程
%K Bi2S3
%K 热电材料
%K 微氧化
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=47EA7CFDDEBB28E0&jid=29DF2CB55EF687E7EFA80DFD4B978260&aid=2C2DE33E892A88205D35D1A601F4EDBE&yid=99E9153A83D4CB11&vid=1D0FA33DA02ABACD&iid=E158A972A605785F&sid=94413940C942B780&eid=94413940C942B780&journal_id=1000-3290&journal_name=物理学报&referenced_num=0&reference_num=18