Electroplated Co-Pt Thick-Film Magnets Prepared in Citric-Acid-Based Plating Baths

• Published in: IEEE Transactions on Magnetics Vol. 53; no. 11; pp. 1 - 3
• Main Authors: Yanai, T., Hamamura, R., Honda, J., Tomita, A., Yamada, H., Fujita, N., Takashima, K., Nakano, M., Fukunaga, H.
• Format: Journal Article
• Language: English; Japanese
• Published: New York IEEE 01.11.2017; Institute of Electrical and Electronics Engineers (IEEE); The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acids; Annealing; Citric acid; Co-Pt; Cobalt; Coercive force; Coercivity; Electroplating; film magnet; hard magnetic material; Magnetic films; Magnetic hysteresis; Magnetic properties; Magnetism; Magnets; Plating; Plating baths; Thick films
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2017.2710351

We electroplated Co-Pt thick films in acid plating baths using a citric acid, and evaluated the magnetic properties of the annealed films. The maximum coercivity value depended on the amount of the citric acid in the bath, and the high coercivity of approximately 800 kA/m was obtained around Co content of 43 at% for the bath with 30 g/L of citric acid. The thickness linearly increased with the increasing plating time, and high plating rate of approximately 3.5 μm/min was obtained. Consequently, 60 μm-thick films were realized keeping at high coercivity.