Dynamic Properties of Low-Alloyed Copper Alloys with Submicrocrystalline Structure Obtained by High Strain Rate Deformation

Abstract—

The mechanical properties of alloys Cu–0.03 wt % Zr and Cu–0.10 wt % Cr with a submicrocrystalline structure formed after dynamic channel angular pressing and subsequent annealing. The properties of the alloys were studied under conditions of shock compression with a pressure of 4.7–7.0 GPa and a deformation rate of (1.3–3.2) × 10⁵ s^–1. It is shown that grain size refinement from 200–400 to 0.3–1.0 μm increases the dynamic elastic limit and the dynamic yield strength of the Cu–0.03% Zr alloy by factors of 1.9 and 1.8, respectively. At the same time, the spall strength is reduced by a factor of 1.4. Subsequent annealing at 400 and 450°C can increase the characteristics of the elastic–plastic transition by factors of 3.0 and 3.7, respectively. This elevates the spall strength to the level of a large crystal analogue. It is determined that the process of dispersing the Cu–0.10% Cr alloy structure to 1.0–5.0 μm leads to an increase in the spall strength by a factor of 1.5 with respect to this value in the coarse grained state, while the dynamic elastic limit and the dynamic yield strength are increased by factors of 3.7 and 2.6, respectively.