Structure and magnetic properties of FePt and FePt-Ag nanostructured magnets by cyclic cold rolling

Journal Article · Sat Apr 15 04:00:00 EDT 2006 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2169545· OSTI ID:20788124

Cui, B Z; Han, K; Garmestani, H; Schneider-Muntau, H J ^[1]

---

1. National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310 (United States)

This paper reports phase components, nanostructure, coercivity mechanism, and hard magnetic properties of FePt and FePt-Ag bulk nanostructured magnets prepared by cyclic cold rolling and subsequent annealing. Annealing temperature of 500 deg. C or higher and annealing time of 120 min or longer are necessary for the as-rolled nanolaminate foils to complete the diffusion and ordering phase transformation. The addition of a small amount of Ag to the as-rolled Fe/Pt foils results in an increase of both the ordering temperature and relative volume fractions of Fe{sub 3}Pt and FePt{sub 3} phases. The diffusion and phase formation mechanism linked to the specific nanostructures of the cold-rolled foils are discussed. The coercivity mechanism of FePt and FePt-Ag nanostructured magnets is analyzed by Gaunt's domain-wall pinning model.

• OSTI ID: 20788124
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 99; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
COERCIVE FORCE
DIFFUSION
FOILS
IRON ALLOYS
MAGNETIC PROPERTIES
NANOSTRUCTURES
PERMANENT MAGNETS
PHASE TRANSFORMATIONS
PLATINUM ALLOYS
ROLLING
SILVER