Microstructural evolution in amorphous-nanocrystalline ZrCu alloy under neutron irradiation

Abstract

An extensive investigation on the microstructural evolution of an amorphous-nanocrystalline alloy (ANA) under neutron irradiation has been conducted by molecular dynamics simulation. The phenomenon of rapid and full annihilation of irradiation-induced vacancies was found in the nanocrystal zone and after structural relaxation, free volumes in the amorphous matrix were systematically self-recovered. An effective self-healing behavior of the nanocrystal zone subsequently sufficed, regardless of the thermal degradation effect caused by the intensity of collision cascades during quenching. As knocked-on atoms were arrested at the phase boundary, it is self-evident that, the mechanism of atomic diffusion was non-existent at the interface between the nanocrystal grain and the neighboring amorphous zone. Consequently, from the foregoing, ANA materials have been found to demonstrate excellent resistance to neutron irradiation and prospectively, the results of this study will potentially facilitate the development of advanced materials with high irradiation resistance.