包覆燃料颗粒碳化硅层的Raman光谱研究

摘要

The Raman spectra of the SiC layers in TRISO particles of fuel elements of HTGRs are studied. Through the analysis of the Raman shifts, the FWHM and intensities, the crystal phases, the residual stress and densities of SiC layers and corresponding spectroscopic features are clarified. The study of the 2D correlation spectrum of first order Raman scattering of SiC layer shows that the LO mode is much more sensitive than the TO mode to the change of density of SiC layer. All these conclusions are significant for synthesising TRISO particles and fuel elements of HTGRs and estimating their qualities,%本文研究了球床高温气冷堆燃料元件中包覆颗粒碳化硅层的Raman光谱.通过分析不同制备条件下的碳化硅层断面的Raman光谱的峰位、半高全宽与强度,明确了包覆颗粒中碳化硅层的晶相特征、密度变化和剩余应力等物性.通过分析不同密度碳化硅层一级Raman峰的同步、异步二维相关谱,发现其LO模较TO模对于密度变化的响应更敏感.这些结论为研究球床高温气冷堆燃料元件包覆颗粒中碳化硅层的结构及其物性有指导意义.