Large lattice strain in individual grains of deformed nanocrystalline Ni

We have used nanobeam electron diffraction to monitor the behavior of individual grains in nanocrystalline Ni during in situ tensile straining in the transmission electron microscope. The diffraction patterns reveal large variations in the magnitude of grain rotation and indicate that grain interiors can experience large lattice distortions (up to 5.5% linear strain). These large distortions may assist grain rearrangement during grain boundary facilitated deformation and are consistent with the behavior expected of nanocrystalline Ni near its predicted peak in strength. (C) 2008 American Institute of Physics.