Influence of slow dynamics effects on the elastic relaxation properties of polycrystalline metal rods

A theoretical model for the formation of ultrasonic signals in metallic microcrystalline rods taking into account the metastable behavior of their defective states is proposed. The influence of metastable states of the defective structure of samples on the features of changes in their resonant frequencies in ultrasonic experiments of fast dynamics is analyzed. The increase in the Young's modulus and the dynamics of changes in resonant vibrations of rods made of aluminum alloy D16T under conditions of free relaxation are explained. Based on the results obtained, the concentration of metastable defects was estimated.