Role of Grain Boundary Sliding in Texture Evolution for Nanoplasticity
Résumé
A new crystal plasticity model is presented to account for the effect of grain boundary sliding (GBS) on texture evolution during large plastic deformation of nanocrystalline materials. In the model, 12 grain boundaries are assigned for each grain and their sliding rates are calculated using Newtonian viscoplasticity. The lattice rotation of the grain interior is computed by taking into account the deformation field modification produced by GBS. The model is employed for predicting the texture evolution in a nanocrystalline Pd–10 at%Au alloy subjected to large strain simple shear, up to a shear strain of 16.8. Two main texture effects due to increasing GBS are identified: high reduction in texture intensity, and tilts of the texture components from their ideal orientations. In the alloy considered, the contribution of GBS to the total strain is identified to be about 30%.