Evolution of magnetic phases upon annealing in glass-coated Fe–Ni–Cu microwires

Abstract The effects of annealing on the magnetic properties of glass-coated Fe–Ni–Cu microwires have been studied. The FCC Ni–Fe particle size increases with the annealing temperature resulting in higher room temperature coercivity. When the annealing temperature is increased to 500°C, a wasp-waisted hysteresis loop is observed which arises from the locking-in of the domain walls by the directional order of atoms due to diffusion under the influence of the local magnetic field. A magnetically hard glass-coated microwire with coercivity of 600 Oe is obtained after annealing at 700°C for 1 h.