SEM/EBSD Analysis of Grain Refinement and Coarsening of Ultra-Fine-Grained Al during Simple Shear Deformation

Although severe plastic deformation causes grain refinement of polycrystalline materials, saturation is known to be caused by simultaneous coarsening. In the present study, for ultra-fine-grained (UFG) pure Al prepared equal-channel angular pressing, we studied and coarsening processes during large simple-shear using scanning electron microscopy/electron backscatter diffraction. The changes crystal orientations in grains as a function position were analyzed log angles rotation around reference axes. This analysis enabled evaluation order magnitude in-plane components geometrically necessary dislocation (GND) density tensors. Detailed shear measured identical regions UFG Al, GND tensors discussed. Our findings indicate that can explained appearance disappearance boundaries composed walls, respectively.