Knowledge about the microstructure of nuclear graphite is critical to the understanding of its irradiation behavior in the reactor. Using micro X‐ray diffraction (μXRD) two‐dimensional (2D) maps, the crystallite character of IG110 and reactor pebble graphite was characterized at the submillimeter range with a spatial resolution of about 5 μm. Various structures in the nuclear graphite were identified by comparing the X‐ray diffraction peak intensity, position, and full width at half maximum (FWHM) 2D maps. The two‐peak feature of the FWHM histograms seen in pebble graphite may be related to the raw coke and natural graphite used as raw materials. With these results, it can be concluded that the μXRD 2D map is an effective method to characterize the microstructure of nuclear graphite.

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使用同步加速器X射线衍射二维图对IG110和反应堆卵石石墨的微观结构表征

关于核石墨微观结构的知识对于了解其在反应堆中的辐射行为至关重要。使用微X射线衍射（μXRD）二维（2D）图，在亚毫米范围内以大约5μm的空间分辨率表征了IG110和反应堆小卵石石墨的微晶特征。通过比较X射线衍射峰强度，位置和半峰全宽（FWHM）二维图，可以识别出核石墨中的各种结构。在卵石石墨中看到的FWHM直方图的两个峰特征可能与原料焦炭和用作原料的天然石墨有关。根据这些结果，可以得出结论，μXRD2D映射是表征核石墨微观结构的有效方法。