An in-situ synchrotron study on microplastic flow of electrodeposited nanocrystalline nickel

Deformation in nanocrystalline (NC) materials is strongly influenced by the presence of a large fraction of grain boundaries. We present a comparative study on the role of intragranular root-mean-square strain and crystallographic texture on recovery processes. The detailed microstructure analysis with conventional X ray diffraction and in-situ synchrotron measurements during deformation are used to understand the various attributes of recovery mechanisms associated with annealing and deformation of electrodeposited NC nickel (grain size = 30 nm). Our results emphasize the dominance of local atomic rearrangements during thermal recovery processes, while deformation induced recovery processes are supported primarily by large-scale dislocation activity. The in-situ deformation of NC samples with two different textures illustrates further the influence of gran boundary character on recovery processes.