Nanostructure, surface and magnetic properties of Co-Cr alloy thin films

Co-Cr films were produced with electrodeposition with different pH at room temperature. The effect of electrolyte pH on the structural, surface morphology and magnetic properties of the films was studied. X-ray diffraction measurement showed that the films have hexagonal close packed structure. For the films deposited at different pH values, the surface morphologies with different-sized globular granules were observed whereas the morphology covered by uniformly distributed nanoscale grains was detected for the surfaces of all films produced from electrolytes with different Cr concentrations. Magnetic properties such as coercivity and saturation magnetization showed strong dependence on the electrolyte solution pH and consequently the crystallite size. The Co-Cr films with low Hc were achieved using relatively low electrolyte pH. The differences observed in the magnetic properties were attributed to the structural changes caused by the electrolyte pH. The Co-Cr films may have the potential applications in magnetic recording and sensors technologies.