熔体旋甩法制备p型填充式方钴矿化合物Ce_(0.3)Fe_(1.5)Co_(2.5)Sb_(12)的微结构及热电性能  

Microstructure and themoelectric properties of p-type filled skutterudite Ce_(0.3)Fe_(1.5)Co_(2.5)Sb_(12) prepared by melt-spinning method

作　　者：郭全胜[1] 李涵[1] 苏贤礼[1] 唐新峰[1] 

机构地区：[1]武汉理工大学材料复合新技术国家重点实验室,武汉430070

出　　处：《物理学报》2010年第9期6666-6672,共7页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(973项目)(批准号:2007CB607501);国家自然科学基金重点项目(批准号:50731006;50672118);国家111计划(批准号:B07040)资助的课题~~

摘　　要：采用熔体旋甩法结合放电等离子烧结技术(MS-SPS)制备了p型填充式方钴矿化合物Ce0.3Fe1.5Co2.5Sb12,研究了熔体旋甩工艺对微结构以及热电性能的影响规律.结果表明,较高的铜辊转速和较低的喷气压力有利于提高熔体的冷却速率,使带状产物晶粒细化.薄带经SPS烧结后得到致密、基本单相、晶粒尺寸均匀细小(150—300nm)的块体.与传统方法制备的试样相比,MS-SPS试样虽然电导率有所降低,但因具有较大的Seebeck系数而获得了相对较高的功率因子.更为重要的是,由于MS-SPS样品中的纳米结构,样品晶格热导率较传统方法制备的Ce0.3Fe1.5Co2.5Sb12降低约30%,因此MS-SPS工艺制备的试样的无量纲热电性能指数ZT与传统方法制备的样品相比有所提高,750K时达到0.55左右.Polycrystalline nanostructured bulk samples of p-type filled skutterudite Ce0.3 Fe1.5 Co2.5 Sb12 have been prepared by melt-spinning （MS） method combined with spark plasma sintering （SPS）. The effects of melt-spinning process on their microstructure and thermoelectric properties have been investigated. The results indicate that the ribbons have finer microstructure with the increasing cooling rate for melt-spun ribbons,resulting from the increasing copper wheel speed and decreasing ejection pressure. Compared with the sample prepared by traditional method,the samples prepared by MS-SPS method have higher power,factor due to the enhanced thermopower,despite the slightly reduced electrical conductivity. Meanwhile,the lattice thermal conductivity of the MS-SPS samples is significantly suppressed. Hence,the thermoelectric performance of the MS-SPS samples is greatly improved,and the figures of merit reach about 0. 55 at 750 K.

关 键 词：熔体旋甩 p型填充式方钴矿化合物 微结构 热电性能 

分 类 号：TB34[一般工业技术—材料科学与工程]