Synthesis and characterization of high-energy ball milled Ni-15%Fe-5%Mo

Nickel-based alloys are commonly used as soft magnetic materials, exhibiting high permeability, low coercivity and high saturation magnetization. In particular, Ni-Fe-Mo alloys have very high relative permeability and low eddy current losses. In this work, nanocrystalline Ni-15%Fe-5%Mo alloy has been synthesized by high-energy ball milling. X-ray powder diffraction (XRPD) has been employed to follow the structural evolution during the ball milling process. The Williamson-Hall method was used to calculate grain size and residual strain from the XRPD data. The grain size was found to be about 8nm and the residual stain was about 0.6% after 100h of milling. The coercivity of the milled powder was found to be affected by grain size and residual strain. The morphology of the powders was examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM).