Rate theory and experimental study of the irradiation induced defects in molybdenum alloy

Molybdenum alloys were irradiated with 3 MeV Mo3+ to 1–10 dpa (displacement per atom) at 330 °C. Transmission electron microscopy (TEM) observation and rate theory simulation were performed to investigate the evolution of defects induced by irradiation. A large number of fine dislocation loops were induced after irradiation, and dislocation network appeared above 5 dpa. Both experiment and simulation show that the growth rates of dislocation loops and voids decrease with the dose, which can be attributed that interstitial atoms and vacancies annihilate with the previously existing defect clusters. No voids were observed in all irradiated specimens due to the inhibition of voids growth in high dose rate and the low mobility at 330 °C.