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石墨的化学腐蚀实验是在ＬＡＳ－２０００二次离子质谱仪的分析室中进行的，用高能氘离子束或与电子束联合辐照石墨，石墨温度从３００—１０００Ｋ可调。辐照下释放的产物用四极质谱探头进行了质谱分析，得到了１．３μＡ、３ｋｅＶ氘束轰击下ＳＭＦ－８００石墨释放氘甲烷（ＣＤ４）的温度特性，在７８０Ｋ处有一个释放高峰。通过分析指出，氘甲烷产额γ除与居留在石墨表面层的氘原子密度ｎＤ有关外，还应和氘甲基（ＣＤ３）的表面层密度ｎＣＤ３相关，即γ＝ＡｎＤｎＣＤ３ｅｘｐ（－ＥＲ／ＲＴ）。实验拟合出石墨表面层中氘甲烷的化学合成激活能ＥＲ＝７．８ｋｃａｌｍｏｌ－１，ＣＤ３和Ｄ的综合脱附激活能Ｅ１＝３５．８ｋｃａｌ·ｍｏｌ－１。从而进一步阐明：在温度高于８００Ｋ后，石墨释放ＣＤ４有急剧下降的温度特性
Graphite chemical corrosion experiments were performed in the LAS-2000 secondary ion mass spectrometer analysis chamber with either a high-energy deuterium ion beam or a combination of electron beam irradiation of graphite with a graphite temperature of 300-1000K. The product released under irradiation was subjected to mass spectrometry with a quadrupole mass spectrometer probe to obtain the temperature characteristic of deuterium methane (CD4) release from SMF-800 graphite under a 1.3μA, 3keV deuterium beam bombardment with a release peak at 780K. According to the analysis, the deuterium yield γ is related to the density nD of deuterium atoms residing in the graphite surface layer and to the surface layer density nCD3 of deuterium methyl (CD3), ie γ = AnDnCD3exp (-ER / RT) . The chemical synthesis activation energy of deuterium methane ER = 7.8kcalmol-1 and the comprehensive desorption activation energy E1 = 35.8kcal · mol-1 of CD3 and D were fitted experimentally. To further clarify: at temperatures higher than 800K, graphite release CD4 has a sharp decline in temperature characteristics