Experimental study on the oxidation behavior and microstructural evolution of NG-CT-10 and NG-CT-20 nuclear graphite

  • Wei Lu
  • Ming-Yang Li
  • Xiao-Wei LiEmail author
  • Xin-Xin Wu
  • Li-Bin Sun
  • Zheng-Cao LiEmail author


NG-CT-10 and NG-CT-20 are newly developed grades of nuclear-grade graphite from China. In this study, their oxidation behaviors were experimentally investigated using thermal gravimetric analysis. Microstructural evolution before and after oxidation was investigated using scanning electron microscope, mercury intrusion, and Raman spectroscopy. The apparent activation energy of NG-CT-10 nuclear graphite is 161.4 kJ/mol in a reaction temperature range of 550–700 °C and that of NG-CT-20 is 153.5 kJ/mol in a temperature range of 550–650 °C. The activation energy in the inner diffusion control regime is approximately half that in the kinetics control regime. At high temperatures, the binder phase is preferentially oxidized over the filler particles and small pores are generated in the binder. No new large or deep pores are generated on the graphite surfaces. Oxygen can diffuse along the boundaries of filler particles and through the binder phase, but cannot diffuse into the spaces between the nanocrystallites in the filler particles. Filler particles are oxidized starting at their outer surfaces, and the sizes of nanocrystallites do not decrease following oxidation.


Nuclear graphite Oxidation NG-CT-10 NG-CT-20 Activation energy 


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Copyright information

© China Science Publishing & Media Ltd. (Science Press), Shanghai Institute of Applied Physics, the Chinese Academy of Sciences, Chinese Nuclear Society and Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy TechnologyTsinghua UniversityBeijingChina
  2. 2.State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advance Materials (MOE), School of Materials Science and EngineeringTsinghua UniversityBeijingChina
  3. 3.Department of Engineering PhysicsTsinghua UniversityBeijingChina

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