Microstructure dependence of magnetic properties on electrochemically produced ternary CuCoNi alloys

Abstract

Ternary CuCoNi alloys were deposited by electrodeposition and the effect of different deposition potentials on the microstructural and magnetic properties of the alloys was investigated. The deposition potential was changed from −1.0 to −1.3 V versus saturated calomel electrode. Anomalous co-deposition occurred for all ternary alloys. All alloys have a face centered cubic (fcc) crystalline structure and the peaks of fcc Cu transformed to those of fcc Ni when the deposition potential was increased from −1.0 to −1.3 V, which was confirmed by the energy dispersive X-ray spectroscopy. The atomic Ni content of the ternary alloys increased from 8 to 33 % when the deposition potential was increased from −1.0 to −1.3 V. On the film surfaces, a specific growth orientation and micro-sticks gradually altered to spherical micro-grains when the deposition potential was increased. Saturation magnetization, M_s and coercivity, H_c of the alloys were significantly affected by different deposition potentials. The M_s value varied between 308 and 674 emu/cm³ when the deposition potential was changed from −1.0 to −1.3 V. And, the H_c gradually decreased from 169 Oe to 112 Oe when the potential increased from −1.0 to −1.3 V. The changes in the magnetic properties of the alloys are related with the variations in the microstructural properties caused by deposition potential. Besides, the anisotropic magnetoresistance magnitudes were found to depend on the deposition potential.