Creep of iron-based BCC alloys in cyclic irradiation conditions. I. Alpha iron

Investigations were conducted into the creep of alpha iron in cyclic electron irradiation (E×2 mev) in the temperature range 200-500°C and applied stresses of 70-350 Pa. The controlling creep mechanisms were determined on the basis of the results of thermoactivation analysis of creep both in thermal and radiation conditions. The results show that depending on the specific mechanism operating in the given conditions, the final result of irradiation can differ: if creep is controlled by the movement of screw dislocations with steps, irradiation results in a reduction of the creep rate whilst in operation of the mechanism controlled by pinning of the edge dislocation by solute atoms the effect can be opposite, i.e., the creep rate increases under the effect of irradiation.