Properties of spatial arrangement of V-type defects in irradiated materials: 3D-modelling

Abstract

We consider the dynamics of pattern formation in a system of point defects under sustained irradiation within the framework of the rate theory. In our study we generalize the standard approach taking into account a production of defects by elastic fields and a stochastic production representing internal multiplicative noise. Using 3D-modelling we have shown that with the damage rate growth, a morphology of clusters composed of vacancies changes. The same effect is observed with variation in the multiplicative noise intensity. Stationary patterns are studied by means of correlation analysis.

Phase field modelling voids nucleation and growth in binary systems

“…In [26] it was shown that by considering a spatially extended system of defects one can monitor the dynamics of dislocation loop densities. Point defects patterning under different irradiation conditions were presented in [27][28][29][30], where the results of numerical simulations of self-organization of point defects into nanometer clusters and defect walls are discussed. Spatially extended models of the system of point defects were used to study voids formation [31] and grains fragmentation under sustained irradiation [32].…”

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

“…Theoretical and experimental investigations of such dissipative structures are widely discussed in literature [7,[17][18][19][20][21]. Numerical studies of defect clusters formation allow one to set up conditions for different kind of patterns emerging in diffusion processes and in processes of defects interaction [22,23]. A production of defects and the resulting microstructure can principally modify the physical and mechanical properties of an irradiated material leading to swelling, hardening and embrittlement [24][25][26][27][28].…”

“…Its influence on arrangement of ensemble of vacancies was studied theoretically in Refs. [22,23,54], where it was shown that depending on internal noise properties different kinds of vacancy structures emerge.…”

Universality and self-similar behaviour of non-equilibrium systems with non-Fickian diffusion

“…In the process of pyramidal islands growth at molecular beam epitaxy, it was found that a structure of pyramids essentially depends on interactions of the elements forming the pattern described by a concentration dependent diffusion coefficient [18][19][20][21]. While studying the arrangement of point defects in solids at particle irradiation according to the swelling rate theory [22,23], it was found that vacancies can arrange into nanosize clusters due to their interactions described by a nonlinear diffusion flux [24][25][26][27]. This effect can lead to abnormal grain growth dynamics when vacancies segregate on the grain boundaries in a stochastic manner [28].…”