Pulsed ion irradiated microstructures in molybdenum

Pulsed irradiation of molybdenum in the temperature range from 1025-1225 K primarily retarded void nucleation. The reduction in nucleation rate could be attributed to a throttling effect caused by annealing out of subcritical void embryos. The more rapid development of the dislocation microstructure during pulsing also contributed to a reduction in void nucleation rate. Once nucleation was complete, microstructural development was not affected by pulsed irradiation compared to steady irradiation. Little pulsing effect on total void swelling or swelling rate was observed. A proposed increase in swelling caused by disintegration of depleted zones during pulsed annealing periods was not observed. (orig.)