Characterization of structural defects in nuclear graphite IG-110 and NBG-18
Characterization of structural defects in nuclear graphite IG-110 and NBG-18
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DOI：
10.1016/j.jnucmat.2013.12.013
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发表时间：
2014-03-01
影响因子：
3.1
通讯作者：
Allen, Todd
中科院分区：
文献类型：
--
作者：
Zheng, Guiqiu;Xu, Peng;Allen, Todd
采用X射线衍射（XRD）、拉曼光谱、扫描电子显微镜（SEM）和高分辨透射电子显微镜（HR-TEM）对核石墨IG-110和NBC-18的结构和显微结构进行了研究。根据XRD和拉曼光谱计算并比较了样品的晶格参数（a）、石墨化度（g）、平行于c方向和垂直于c方向的晶粒尺寸（L-c和L-垂直于）、各向异性（B）以及面内晶粒尺寸（L-a）。结果表明，IG-110具有较大的晶粒尺寸和较高的石墨化度，但各向异性低于NBC-18。这些差异归因于焦炭来源和制造工艺的性质。此外，通过SEM和HR-TEM图像观察和表征了孔隙和结晶填料颗粒的形状、粘结剂和填料之间的界面、Mrozowski裂纹和纳米裂纹以及向错缺陷。讨论了IG-110和NBG-18在微观结构上的异同。这项工作的结果为指导下一代核电站（NGNP）设计中核石墨的选择提供了有用的信息。(C)2013爱思唯尔有限公司版权所有。
Nuclear graphite IG-110 and NBC-18 were examined using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscope (SEM) and high resolution transmission electron microscope (HR-TEM) to understand the structure and microstructure of nuclear graphite. The lattice parameter (a), degree of graphitization ((g) over bar), crystallite size parallel and perpendicular to c-direction (L-c and L-perpendicular to), anisotropy (B), as well as in-plane crystallite size (L-a) were calculated and compared based on XRD patterns and Raman spectra. Results indicate that IG-110 has a larger crystallite size and higher degree of graphitization, but lower anisotropy than NBC-18. These differences are attributed to the properties of coke source and manufacturing processes. Additionally, the shape of the pores and crystallized filler particles, the interface between binders and fillers, Mrozowski cracks and nano-cracks, and the defects of disclination were observed and characterized from SEM and HR-TEM images. The similarities and differences in microstructure between IG-110 and NBG-18 are discussed. The results in this work provide useful information to guide selection of nuclear graphite for the design of next generation nuclear plants (NGNP). (C) 2013 Elsevier B.V. All rights reserved.