摘要
采用燃烧合成-热处理工艺制备热电材料β-FeSi2,研究了Cu掺杂和不同的硅含量对β-FeSi2相变的影响。利用X射线衍射仪和扫描电子显微镜分析了合成的铁硅间化合物的相组成及其微观形貌。结果表明:掺杂0.5 at%的Cu在热处理过程中能提高共析反应(α→β+Si)的反应进程,完全地将α-Fe2Si5转变为β-FeSi2,形成P型半导体。在混料阶段按Fe∶Si=1∶3的原子比例制备β-FeSi2,XRD分析表明,过量的Si单质提高了Si+ε→β的相转变过程,很大程度上能够消除ε相,增加β-FeSi2的含量。
Thermoelectric material β-FeSi2 was prepared by combustion synthesis and heat treatment process.Effects of copper doped and different silicon content on phase transformation of β-FeSi2 were studied.The phase composition and microstructure of Fe-Si intermetallics were investigated by means of X-ray diffraction（XRD） and scanning electronmicroscopy（SEM）.The results show that doping 0.5 at% copper can accelerate eutectoid reaction process（α→β＋Si）during heat treatment,and the transformation from α-Fe2Si5 phase to β-FeSi2 phase is complete and finally formed P-type semiconductor.Samples of β-FeSi2 were prepared by combustion synthesis and heat treatment with the mixture,in which the atomic ratio of Fe to Si was 1∶3,and the XRD analysis shows that the excessive content of silicon accelerated the phase transformation of Si＋ε→β,and ε phase is eliminated to a large extent,the productivity of β-FeSi2 increased.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2011年第5期17-21,共5页
Transactions of Materials and Heat Treatment
基金
甘肃省自然科学基金项目(1014RJ2A010)
关键词
热处理工艺
CU掺杂
硅含量
Β-FESI2
相转变
heat-treatment process
copper doped
silicon content
β-FeSi2
phase transformation
