Voids and Other Neutron-Produced Microstructure in Mo and Mo-0.5 at. % Ti as Studied by Positron-Annihilation Techniques

摘要

Specimens of Mo and Mo-0.5 at. % Ti which have been irradiated with neutrons (approx. 10 exp 22 n/cm exp 2 , E > 0.1 MeV) at temperatures between 425 and 1500 exp 2 C have been studied using both lifetime and Doppler-broadening measurements. Both the shape parameter and the intensity of the lifetime component from positrons trapped at voids define swelling as a function of temperature in a way that is independent of the neutron fluence. The relative swelling as a function of irradiation temperature and the swelling peak (approx. 750 exp 0 C) are well defined, but no information on the magnitude of the void volume is obtainable. In the determination of the shape and peak of the derived swelling curve, the positron analysis is more definitive than similar determinations using transmission electron microscopy. (ERA citation 06:014400)