Crystallization induced ordering of hard magnetic L1{sub 0} phase in melt-spun FeNi-based ribbons

Journal Article · Sun May 15 00:00:00 EDT 2016 · AIP Advances

DOI:https://doi.org/10.1063/1.4952968· OSTI ID:22611509

Sato, Kazuhisa; Sharma, Parmanand; Zhang, Yan; Takenaka, Kana; Makino, Akihiro ^[1]

---

1. Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

The microstructure of newly developed hard magnetic Fe{sub 42}Ni{sub 41.3}Si{sub x}B{sub 12-x}P{sub 4}Cu{sub 0.7} (x = 2 to 8 at%) nanocrystalline alloy ribbons has been studied by transmission electron microscopy (TEM) and electron diffraction. A high-density polycrystalline grains, ∼30 nm in size, were formed in a ribbon after annealing at 673 K for 288 hours. Elemental mapping of the annealed specimen revealed the coexistence of three regions, Fe-rich, Ni-rich, and nearly equiatomic Fe-Ni, with areal fractions of 37%, 40%, and 23 %, respectively. The equiatomic L1{sub 0}-type ordered phase of FeNi was detected in between the Fe and Ni-rich phases. The presence of superlattice reflections in nanobeam electron diffraction patterns confirmed the formation of the hard magnetic L1{sub 0} phase beyond any doubt. The L1{sub 0} phase of FeNi was detected in alloys annealed in the temperature range of 673 to 813 K. The present results suggest that the order-disorder transition temperature of L1{sub 0} FeNi is higher than the previously reported value (593 K). The high diffusion rates of the constituent elements induced by the crystallization of an amorphous phase at relatively low temperature (∼673 K) are responsible for the development of atomic ordering in FeNi.

• OSTI ID: 22611509
• Journal Information: AIP Advances, Vol. 6, Issue 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOYS
AMORPHOUS STATE
ANNEALING
BORON COMPOUNDS
COPPER COMPOUNDS
CRYSTALLIZATION
DIFFUSION
ELECTRON DIFFRACTION
IRON COMPOUNDS
MAGNETIC MATERIALS
MICROSTRUCTURE
NANOSTRUCTURES
NICKEL COMPOUNDS
ORDER-DISORDER TRANSFORMATIONS
PHOSPHORUS COMPOUNDS
POLYCRYSTALS
SILICON COMPOUNDS
SUPERLATTICES
TRANSITION TEMPERATURE
TRANSMISSION ELECTRON MICROSCOPY