Phase-field simulation of Cu enriched nanoparticles with variation of defects migration energy under neutron irradiation

Abstract

Neutron radiation induces point defects and affects the diffusivity of atoms and the kinetics of precipitation. The phase-field simulation reveals the influence of migration energy of vacancy on the radiation-enhanced precipitation in Fe–Cu alloy. The study shows that radiation-enhanced diffusion (RED) also depends on the diffusivity of vacancy-associated migration energy and not only on the dose rate; the low migration energy of vacancy results in accelerated precipitation and a higher volume fraction of Cu precipitates. Interestingly, decreasing migration energy from 1.0 eV to 0.9 eV results in a 30% increase in the precipitates’ volume fraction. Also, the combination of the lowest dose rate 5.0 × 10−3 dpa s−1 and highest migration energy 1.0 eV delays the precipitation. The study also examines the influence of migration energy of vacancy on the radius of Cu precipitates. The lowest migration energy, 0.9 eV, increases the radius up to one-third. Finally, the work presents the drawbacks of the analytical digital image processing technique in the quantitative comparison with the script.