Simulations of texture evolution in heavily deformed bulk nanocrystalline nickel

The texture evolution in cold-rolled coarse-grained (CG) and nanocrystalline (NC) Ni sheets is simulated by the viscoplastic self-consistent and Taylor-type dislocation-based plasticity models, respectively. The simulated three-dimensional crystal orientation distributions are directly compared with the X-ray diffraction experimental measurements. Both models capture very well the texture development in the CG Ni, although the simulated brass texture component, i.e., {1 0 0}<1 1 2>, is slightly weaker than the experimental value. In the simulations of the texture evolution for the NC Ni, we add a shearing-strain component ɛ13 to the total velocity gradient tensor and reduce the number of active {1 1 1}〈1 1 0〉 slip systems from 12 to 8. The new constrained conditions retard the development of the brass component and lead to the enhancement in the initial cube orientation, i.e., {1 0 0}<0 0 1>, in agreement with the experimental observations in the cold-rolled NC Ni sheets. The present investigations suggest that the dislocation-based plasticity mechanism is still the dominant one in affecting the deformation behavior of NC Ni with an initial grain size of ∼28 nm.