Effect of Atomic Collision Cascade Formation on Precipitate Growth Kinetics in the Structural Materials of Reactors Under Neutron Irradiation

Resumo

The concentration and average size of phase precipitates enriched with impurity atoms in materials under irradiation, specifically, copper, nickel, and manganese, in the vessel steel of a reactor strongly influence the strength characteristics. This work proposes a theoretical model of the effect of atomic-collision cascades in a material irradiated by fast neutrons on the growth kinetics of copper enriched precipitates at the coalescence stage. The changes in the size distribution function, the time dependences of the concentration and average size as a function of the irradiation dose of fast neutrons at the coalescence stage, as well as the asymptotic changes in the critical size of the deposits are found analytically for large precipitates. The theoretical results are compared with the experimental results.