Circumferential shear strain in torsion-based severe plastic deformation

  The dependence of the circumferential shear strains of two different shear modes in a cylindrical coordinate system on the shear planes during a torsion-based severe plastic deformation is investigated using strain–displacement relationships. Contrasting trends in the circumferential shear strains (increasing εzθ and decreasing εrθ with radial distance from the center in the axial plane torsion and radial plane torsion, respectively) are demonstrated, which are in good agreement with published results.