EBSD Analysis on Deformation of Nanocrystals in ECAP-Processed Copper

Abstract

Nanocrystalline materials produced by severe plastic deformation techniques have captured great attention because of the excellent mechanical properties. Equal channel angular pressing (ECAP) is especially attractive because the simple technique can produce large bulk samples with little residual porosity, elevating the strength without adding expensive alloying elements. Materials processed by ECAP consist of nanoscopic and submicron grains. Though ECAP holds many advantages in terms of practical application over other severe plastic deformation process that can produce only nanocrystalline surface layers, the deformation and damage mechanism in the characteristic microstructure of ECAP-processed materials is not clarified. For the detailed microscopic observation, electron backscattering diffraction (EBSD) technique is a useful tool that enables investigation based on crystallographic orientation. In this paper, EBSD analysis was made on pure copper processed by ECAP in order to investigate the mechanism of deformation and damage in the microstructure with nanoscopic and submicron structures, with special attention to the grain boundary sliding of nanocrystals.