Strain localization and superplastic-like flow in copper at high temperature

The localization of plastic deformation at high temperature and its influence on the mechanical performance of polycrystalline copper were studied. The results showed that the instability of the load during high-temperature deformation is caused by the localization of plastic flow within shear bands. This in turn leads to heterogeneity of the dislocation structure and becomes a motive for selective static recrystallization along shear bands. Under appropriate conditions the balance between the formation of new shear bands and recrystallization (or recovery) within already inactive shear bands leads on a global scale to superplastic-like behaviour of the metal.