Effect of shock-wave loading on the internal microstructure and mechanical properties of fine-grained copper

Abstract

It is shown that preloading of fine-grained copper with a the grain size of 0.5 m by a shock wave of intensity ≈25–50 GPa does not lead to changes in its internal microstructure and mechanical properties, and the dislocation density increases only slightly from 1.8·10¹¹ cm ˉ² in the initial state to (3.1–3.6)·10¹¹ cmˉ² after shock-wave loading. An increase in shock wave intensity to pressures >55 GPa leads to a decrease in the dislocation density to 2.5·10⁹ cm ˉ² , an increase in the grain size to ≈19µm, the occurrence of microtwins inside the grains, and a reduction in the mechanical properties of fine-grained copper to the level of coarse-crystalline copper