Ferromagnetic behavior of nanocrystalline Cu–Mn alloy prepared by ball milling

Abstract

50Cu–50Mn (wt%) alloy was produced by ball milling. The milling was continued up to 30h followed by isothermal annealing over a four interval of temperature from 350 to 650°C held for 1h. Crystallite size, lattice strain, lattice parameter were determined by Rietveld refinement structure analysis of X-ray diffraction data. The amount of dissolved/precipitated Mn (wt%) after ball milling/milling followed by annealing was calculated by quantative phase analysis (QPA). The increase of coercivity could be attributed to the introduction of lattice strain and reduction of crystallite size as a function of milling time. Electron paramagnetic resonance and superconducting quantum interface device analysis indicate that soft ferromagnetic behavior has been achieved by ball milled and annealed Cu–Mn alloy. The maximum coercivity value of Cu–Mn alloy obtained after annealing at 350°C for 1h is 277Oe.