A soft magnetic CoNiFe film with high saturation magnetic flux density and low coercivity

Tetsuya Osaka (), Madoka Takai, Katsuyoshi Hayashi, Keishi Ohashi, Mikiko Saito and Kazuhiko Yamada
Additional contact information
Tetsuya Osaka: Waseda University, and Kagami Memorial Laboratory for Material Science and Technology, Waseda University
Madoka Takai: Waseda University, and Kagami Memorial Laboratory for Material Science and Technology, Waseda University
Katsuyoshi Hayashi: Waseda University, and Kagami Memorial Laboratory for Material Science and Technology, Waseda University
Keishi Ohashi: NEC Ibaraki Ltd, Sekijomachi
Mikiko Saito: NEC Corporation
Kazuhiko Yamada: NEC Corporation

Nature, 1998, vol. 392, issue 6678, 796-798

Abstract: Abstract Magnetic materials are classed as ‘soft’ if they have a low coercivity (the critical field strength Hc required to flip the direction of magnetization). Soft magnetic materials are a central component of electromagnetic devices such as step motors, magnetic sensors, transformers and magnetic recording heads. Miniaturization of these devices requires materials that can develop higher saturation flux density, Bs, so that the necessary flux densities can be preserved on reducing device dimensions, while simultaneously achieving a low coercivity. Common high-Bs soft magnetic films currently in use are electroplated CoFe-based alloys1,2,3,4 electroplated CoNiFe alloys5,6,7 and sputtered Fe-based nanocrystalline8,9,10,11 and FeN films12,13,14. Sputtering is not suitable, however, for fabricating the thick films needed in some applications, for which electrochemical methods are preferred. Here we report the electrochemical preparation of a CoNiFe film with a very high value of Bs (2.0–2.1 T) and a low coercivity. The favourable properties are achieved by avoiding the need for organic additives in the deposition process, which are typically used to reduce internal stresses. Our films also undergo very small magnetostriction, which is essential to ensure that they are not stressed when an external magnetic field is applied (or conversely, that external stresses do not disrupt the magnetic properties). Our material should find applications in miniaturization of electromechanical devices and in high-density magnetic data storage.

Date: 1998
References: Add references at CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.nature.com/articles/33888 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:392:y:1998:i:6678:d:10.1038_33888

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/33888

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().