Зеренная структура, геометрически необходимые дислокации и частицы вторых фаз в поликристаллах микрои мезоуровня

The paper considers the influence of size effects on dislocation structure and second-phase particles. Particular attention is given to the effect of grain sizes on scalar dislocation density, geometrically necessary dislocation density and parameters of particles formed at grain boundaries. It is found that there exist three critical grain sizes with which the mechanisms of deformation and hardening of polycrystals in the vicinity of grains change. Special emphasis is placed on stabilization of the submicrocrystalline grain structure by second-phase particles located at the grain boundaries.