Crystal plasticity simulations of Cube in-grain fragmentation in aluminium: Influence of crystal neighbor orientation

Abstract

The orientation evolution and the in-grain microtexture of Cube-oriented FCC crystals in aluminium are investigated using crystal plasticity simulations. The influence of crystallographic orientation of neighbor grains on Cube microtexture is presented. Several loading conditions from ideal plane strain compression to compression with superimposed shear loadings are simulated both during cold-rolling and hot-rolling. During hot-rolling, activity of non-octahedral slip systems is considered. The obtained results highlight the strong influence of different neighbors on the development of in-grain Cube fragmentation and question or in other cases support early models describing evolution of in-grain Cube rotation. During hot-rolling, non-octahedral slip systems stabilize Cube, but this depends on orientations of neighboring grains. In hot rolling, when Cube is surrounded by grains of Brass crystallographic orientation, it undergoes significant fragmentation despite the activity of non-octahedral slip systems; while S, Copper, or Goss oriented adjacent grains do not promote Cube misorientation. During cold rolling, the most effective orientations to misorient Cube are Brass and S. Superposition of shear loadings to thickness compression is beneficial for Cube fragmentation but at the end of the deformation process, the remaining Cube volume fraction depends on the signs of the shear components. However, for all orientations of neighbor grains, ND-RD shear (FND-RD) of deformation gradient has stronger influence than RD-ND shear (FRD-ND) on promoting Cube in-grain splitting.