摘要
功能耐热陶瓷碳化硅（ＳｉＣ）是一种高温工程中有希望的候选材料，这里采用工业ＳｉＣ作半成品烧结而成的粉末样品。中子衍射数据采用多相Ｒｉｅｔｖｅｌｄ最小二乘轮廓精修法处理，拟合结果表明，此样品除主相２Ｈ相（空间群为Ｐ６＿３ｍｃ）外，还有４Ｈ相（Ｃ６ｍｃ）和６Ｈ相（Ｃ６ｍｃ）以及残余杂质ＳｉＯ＿２的α相（Ｆｄ３ｍ）成分。４个相的丰度均已定出。结果表明，引进新的多相拟合程序后，利用国内的中子衍射技术不仅可确定材料的结构，而且可在多相混杂情况下得到各自的丰度，从而增加了中子衍射方法在材料科学中的应用。
Functional heat-resistant ceramics silicon carbide SiC is a highly feasible material for hightemperature engineering applications. The SiC investigated is sintered into powder sample usingindustrial SiC as semifinished materials. The neutron diffraction is performed on the powder neu-tron diffractometer at l5 MW heavy water research reactor of the China Institute of AtomicEnergy. The least-squares crystal structure and profile refinements are undertaken with the mul-tiphase Rietveld analysis program Fullprof,which was from ILL,Grenoble,France. The resultsfitted for neutron data show that besides the main phase of 2H(space group of P6_3mc),there are4H(C6mc), 6H(C6mc)and α-SiO_2(Fd3m) of residual impurity.The abundance of 4 phases are2H(73.1 ±2.0)%,4H(12.8±7)%, 6H(14.0±1.1)% and α-SiO_2<0.1%,The resultshows that neutron powder diffraction is becoming more and more powerful on materials science,while the new multiphase Rietveld profile program is used.The neutron diffraction analysis can beused not only to determine the structure of materials and but also to obtain the abundanc of mix-ture phases.
出处
《原子能科学技术》
EI
CAS
CSCD
北大核心
1995年第2期133-139,共7页
Atomic Energy Science and Technology
基金
国际机构IAEA的赞助
关键词
中子衍射
多相分析
功能陶瓷
碳化硅
耐热陶瓷
Neutron diffraction Multiphase analysis Functional ceramics HeatresistantSiC
