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研究各向同性微细颗粒石墨ZXF-5Q的微结构及熔盐浸渗特性。使用光学显微镜、压汞仪、真密度仪、透射电子显微镜、X射线衍射仪以及拉曼光谱仪,对其气孔、煅烧裂纹、Mrozowski裂纹及晶体结构进行表征。结果表明,ZXF-5Q拥有均匀分布的气孔,非常小的入孔孔径(0.4μm),数量众多的透镜状Mrozowski裂纹以及良好的晶体结构。熔盐浸渗实验在不同压力(分别为1、3、5个大气压)650℃环境下进行。利用扫描电子显微镜和X射线能谱仪对其浸渗特性进行了观察分析。研究表明,由于其非常小的入口孔径,ZXF-5Q在5个大气压外加压强环境下依然可以很好阻止熔盐浸渗。尽管没有浸渗发生,在ZXF-5Q内部可以发现球形熔盐颗粒,可能是熔盐蒸汽凝结造成的。“,”The microstructure and molten salt impregnation characteristics of a micro-fine grain isotropic graphite ZXF-5Q from Poco Inc. was investigated. The microstructural characteristics of the pores caused by gas evolution, calcination cracks, Mrozowski cracks, and the crystal structure were characterized by optical microscopy, mercury porosimetry, helium pycnometry, transmission electron microscopy, X-ray diffraction and Raman spectroscopy. Results show that the ZXF-5Q has uniformly-distributed pores caused by gas evolution with very small entrance diameters ( ~0. 4 μm), and numerous lenticular Mrozowski cracks. Molten salt impregnation with a molten eutectic fluoride salt at 650℃ and 1, 3 and 5 atm, indicate that ZXF-5Q could not be infiltrated even at 5 atm due to its very small pore entrance diameter. Some scattered global salt particles found inside the ZXF-5Q are possibly formed by condensation of the fluoride salt steam during cooling.