Severe plastic deformation introduced by rotation shear

A newly invented method, called the rotation shear method, to achieve the high strain by the rotation shear is introduced in this paper. Equations for the calculation of the strain and the strain rate are presented. An experiment was performed with pure aluminum and the results showed that a shear strain up to 8.37 was achieved and the transmission electron microscope observation confirmed that an ultra-fine grained material with the size below 700 nm was obtained.