A Langevin model for real-time Brownian dynamics of interacting nano-defects in irradiated metals
In-situ real-time electron microscope observations of metals irradiated with ultra-high-energy electrons or energetic ions show that the dynamics of microstructural evolution in these materials is strongly influenced by long-range elastic interactions between mobile nano-scale radiation defects. Treating long-range interactions is also necessary for modelling microstructures formed in ex-situ high-dose-rate ion-beam irradiation experiments, and for interpolating the ion-beam irradiation data to the low-dose-rate limit characterizing the neutron irradiation environments of fission or fusion power plants. We show that simulations, performed using an algorithm where nano-scale radiation defects are treated as interacting Langevin particles, are able to match and explain the real-time dynamics of nano-defects observed in in-situelectron microscope experiments.