Orientation-dependent grain growth in a bulk nanocrystalline alloy during the uniaxial compressive deformation

The microstructural evolution during the uniaxial compression of an as-deposited bulk nanocrystalline (nc) Ni-Fe (average grain size d approximate to 23 nm) at ambient temperature was investigated by the high-energy x-ray diffraction (HEXRD) and the transmission-electron microscopy (TEM). HEXRD measurements indicated that the grain growth occurred in the nc Ni-Fe alloy during the uniaxial compression tests and that the grain growth shows orientation dependence, i.e., the grains preferentially grow perpendicular to the loading direction. This preferred grain growth was further confirmed by the TEM observations, indicating that the grains were elongated after the compressive plastic deformation. (c) 2006 American Institute of Physics.