Granular magnetoresistance ribbon material suitable for isotropic magnetic field transducers

Magnetic granular CoCu alloy ribbons were prepared by the melt‐spun method, and the structural, magnetotransport, magnetic properties, and the effects of annealing on these properties were studied by x‐ray diffraction, vibrating sample magnetometer, and magnetoresistance (MR) measurements at room temperature. Giant magnetoresistance was observed over a broad range of Co concentrations with a maximum MR ratio of 7.8% (at x=0.20 and 500 °C annealing) under a magnetic field of 20 kOe at room temperature. It is found that the relationship between MR and magnetic field H depended strongly on the annealing temperature and a linear MR‐H relation could be obtained at an optimum annealing condition. The MR ratio did not depend on the direction between H and electric current I. These features are very suitable for making isotropic magnetic field transducers.