Modeling self-organization of nano-size vacancy clusters in stochastic systems subjected to irradiation

A study of the self-organization of vacancy clusters in irradiated materials is presented. Using a continuum stochastic model we take into account dynamics of point defects and their sinks with elastic interactions of vacancies. Dynamics of vacancy clusters formation is studied analytically and numerically under conditions related to irradiation in both reactors and accelerators. We have shown a difference in patterning dynamics and studied the external noise influence related to fluctuation in a defect production rate. Applying our approach to pure nickel irradiated under different conditions we have shown that vacancy clusters having a linear size 6 nm can arrange in statistical periodic structure with nano-meter range. We have found that linear size of vacancy clusters at accelerator conditions decreases down to 20%, whereas a period of vacancy clusters reduces to 6.5%.