Radiation annealing of reactor graphite after neutron irradiation

The reactor graphite specimens initially irradiated at 310-450 K by the fluences 5x1021, 9x1021, 1,3x1022 n/sm2 (E>0,18 MeV) were repeatedly irradiated at 620-1200 K by the fluences up to 2,5x1021 n/sm2. Simultaneously the control specimens of reactor graphite and nongraphitized half finished product were irradiated. It is shown that irradiation annealing of preirradiated specimens leads to the more considerable shrinkage that of the control specimens