Electrodeposition of a High Magnetostriction CoFe Film.

Journal Article · Tue Sep 01 04:00:00 EDT 2015

OSTI ID:1427218

Pillars, Jamin Ryan ^[1]; Langlois, Eric ^[1]; Arrington, Christian Lew ^[1]; Monson, Todd C. ^[1]; Hollowell, Andrew E ^[1]; Rodriguez, Mark A. ^[1]

---

1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

The development of an electrodeposition process for cobalt/iron (CoFe) alloys with minimal oxygen concentration and controlled stoichiometry is necessary for the advancement of magnetostrictive device functionalities. CoFe alloy films were electrodeposited out of a novel chemistry onto copper test structures enabling magnetic displacement testing for magnetostriction calculations. Using a combination of additives that served as oxygen scavengers, grain refiners, and complexing agents in conjunction with a pulsed plating technique, CoFe films were synthesized at thicknesses as high as 10μm with less than 8 at% oxygen at a stoichiometry of 70-75% Co and 25-30% Fe. X-Ray diffraction (XRD) analysis confirmed that these films had a crystal structure consistent with 70% Co 30% Fe Wairuaite with a slight lattice contraction due to Co doping in the film. A novel characterization technique was used to measure the displacement of the CoFe films electrodeposited, as a function of applied magnetic bias, in order to determine the saturation magnetostriction (λS) of the material. With this chemistry and a tailored pulse plating regime, λS values as high as 172 ± 25ppm have been achieved. This is believed by the authors to be the highest reported value of magnetostriction for an electrodeposited CoFe film.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 1427218
• Report Number(s): SAND2015--7868J; 603714
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE