TEM Study of Nickel under In-situ Helium/Krypton Dual-Beam Irradiation

摘要

Recent interest in molten salt reactors calls for research on nickel alloys because of its high-temperature strength and corrosion resistance [1]. Under neutron irradiation, transmutation reaction results in helium that segregates and forms bubbles along grain boundaries, leading to intergranular cracking, the so-called high-temperature helium embrittlement. Helium is strongly bound to vacancies. A detailed understanding of the interplay between helium and vacancies under various irradiation conditions and material sink density is still lacking. This work investigated the synergistic effect of displacement damage and helium implantation in pure nickel by in situ TEM with dual-ion beams at the IVEM-Tandem Facility in Argonne National Laboratory.