[2H09-14] Irradiation Effect 2

[2H10] Effects on Mn addition on dislocation loop formation in ferritic alloys

*Li Ranran¹, Hideo Watanabe¹, Farong Wan (1. Kyushu Univ.)

Keywords:Dislocation loop, Ferritic alloys, Mn

Formation of interstitial and vacancy typed dislocation loops are recognized as the most common phenomena in irradiated materials. But few studies were given in vacancy typed dislocation loop formation in Fe model alloys. In this study, Fe-1.4wt.%Mn alloy was preimplanted with hydrogen ions at room temperature with the tandem accelerator at Kyushu Unversity. Small defects developed into large dislocation loops during the followed annealing at the high temperatures. The nature of dislocation loops was investigated during the electron irradiation at the corresponding annealing temperature by in situ observation of high-voltage electron microscope (HVEM). It found that all the dislocation loops were interstitial-type loops when annealed at 400℃. Shrinking processes of small amount of dislocation loops under the electron irradiation were observed when annealed at 450℃ and 500℃. On the other hand, when annealed at 450℃, more and more voids were formed gradually during the electron irradiation, which can be guessed that the vacancy-type loops had formed at 450℃.