Abstract:
We have studied high strain rate deformation of aluminum alloy 01570S with bimodal structure obtained by equal channel angular pressing. It has been demonstrated that, at certain parameters of structure and temperature-strain rate modes of dynamic loading, the alloy can exhibit a high coefficient of strain rate sensitivity $m\sim$ 0.4 characteristic for structural superplasticity upon quasi-static loading. An explanation of this effect in terms of the theory of nonequilibrium grain boundaries is proposed.