The materials used in the first wall of ITER and fusion power plants will be required to withstand neutron bombardment produced in fusion plasmas. The development of models describing the structural defects in fusion materials has become an important element in the development of a prototype of a fusion power reactor. Modelling of structural defects requires new modelling approaches giving theoretical predictions that could be experimentally validated. Here, the Fokker–Planck kinetic equation was proposed for modelling of nanovacancies, nanovoids and dislocation loops in fusion materials under cascade producing irradiation. It will be shown that in the simplest approximation that includes the effects of the statistical and cascade induced fluctuations, the kinetics of the evolution of the nanostructural defects could be described by the Fokker-Planck equation for the defect size distribution function. The proposed model could be applied to fusion materials under irradiation conditions that represent those of the first wall of a fusion reactor.

Application of the Fokker Planck Approach for Modelling of Nano-Structural Defects in Fusion Materials. T.Apostolova, T.Troev: Journal of Physics - Conference Series, 2010, 207[1], 012034