Pilipenko A. Internal friction of copper and composites on its basis after combined plastic deformation

The dissertation is devoted to the establishment of regularities in the changing of low frequency internal friction and shear modulus of copper and composites on its basis under the influence of various schemes of combined plastic deformation with using deformation by a simple shear. The created automated equipment with the improved functional posibilities and the developed software. It has been shown that combined plastic deformation with displacement increases the value of internal friction of copper (up to 30 %) and reduces the temperature of the beginning of recrystallization processes in comparison with samples after monotonous molding due to the formation of a submicron crystalline structure with non-equilibrium grain boundaries. An increase in the dynamic shear modulus (up to 50 %) of such copper, which is observed with an increase in the temperature of heat treatment, is due to the emergence of twin annealing and the growth of their density. A physical model of two-component single-phase material is proposed. It adequately describes the experimental results.