The study of graphite disordering using the temperature dependence of ion-induced electron emission

The temperature dependences of ion-induced electron emission yield γ(T) under 6-30 keV N2+, Ne+, Ar+ and 15 keV N+ high-fluence ion irradiation of polycrystalline graphite at normal ion incidence have been analyzed to trace the structure change dependence depending on irradiation temperature and the level of radiation damage v measured in dpa (displacements per atom). It has been found that, under irradiation at room temperature, the threshold value for graphite lattice disordering equals vd ≈ 60 dpa for noble gas ions (Ar+, Ne+) and νd ≈ 40 dpa for N2+.