Deformation mechanisms in nanocrystalline metals: Insights from in-situ diffraction and crystal plasticity modelling

In-situ mechanical testing during X-ray diffraction is performed on electro-deposited nanocrystalline Ni. It is found that the evolution of inter-granular stresses with plastic deformation is altered compared to what is usually found for coarse-grained metals. The results are rationalized by insights gained from molecular dynamics and quantized crystal plasticity modelling.

► In-situ X-ray diffraction reveals little build-up of inter-granular stress in nc Ni.
► This may be explained using a new Quantized Crystal Plasticity model.
► The presence of a broad distribution of critical stresses is essential.