Shear band evolution of nanocrystalline Ni under obvious plastic deformation

At obvious plastic deformation stage, an in-situ TEM tensile testing for the nanocrystalline Ni was conducted to investigate the microscopic physical mechanisms during the development of shear bands. Thus, a corresponding model was optimized. The results show that in the nanometer scale, with the increasing of grain size, shear band width increases and the trend of strain softening becomes more obvious. The generation of shear band in smaller grain is earlier than that in bigger grain. The intrinsic length scale increases first with the increasing of grain size and then decreases. The distribution of shear strain in shear band is also obtained. The value of shear strain is zero at two boundaries of the shear band and is the maximum at center of the shear band.