The plastic deformation, under plane-strain constrained shear, of a single crystal having one active slip system was investigated within continuum dislocation theory. By introducing a twinning shear into the energy of the crystal, it was shown that - within a certain straining range - the formation of deformation twins became energetically preferred. An energetic threshold was determined for the onset of twinning. A rough analysis described qualitatively not only the evolving volume fractions of twins, but also their number, during straining. The evolution of deformation twins and of the dislocation network at non-zero dissipation was analyzed. The corresponding stress–strain hysteresis, the evolution of the plastic distortion, the twin volume fractions and the dislocation densities were deduced.

A Continuum Model for Initiation and Evolution of Deformation Twinning. D.M.Kochmann, K.C.Le: Journal of the Mechanics and Physics of Solids, 2009, 57[6], 987-1002