Magnetic properties and magnetic hardening mechanism of Pt‐Co‐B alloys

ABSTRACTThe state-of-the-art description of the magnetic hardening mechanism in the sintered Nd-Fe-B permanent magnet is given. Recent experimental results concerning the coercivity-anisotropy (Hc -HA) correlation in B-rich Pr-Fe-B and Nd-Fe-B sintered magnets and the inhluence of the surface conditions of the sintered Nd-Fe-B magnets on the coercivity are reported. These results are interpreted in terms of the μ0Hc versus cμ0 HA -NIS plot, where I is the spontaneous magnetization of R2 Fe14 (R=Pr or Nd) and N the effective demagnetization field coefficient.

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Nanocrystalline and Nanostructured High-Performance Permanent Magnets

MRS Proceedings ◽

10.1557/proc-674-u2.4 ◽

2001 ◽

Vol 674 ◽

Cited By ~ 4

Author(s):

D. Goll ◽

W. Sigle ◽

G.C. Hadjipanayis ◽

H. Kronmüller

Keyword(s):

Magnetic Properties ◽

High Performance ◽

Permanent Magnets ◽

Maximum Energy ◽

High Quality ◽

Hardening Mechanism ◽

Temperature Dependences ◽

Complex Correlation ◽

Energy Products

ABSTRACTThe rather complex correlation between the microstructure and the magnetic properties is demonstrated for two types of high-quality RE-TM permanent magnets (pms), namely nanocrystalline RE2Fe14B (RE = Nd,Pr) and nanostructured Sm2(Co,Cu,Fe,Zr)17 pms. The detailed analysis of this correlation for both pm materials leads to a quantitative comprehension of the hardening mechanism enabling the optimization of their magnetic properties and temperature dependences. In the case of RE2Fe14B, isotropic bonded pms are fabricated showing maximum energy products in the order of 90 kJ/m3. In the case of Sm2(Co,Cu,Fe,Zr)17, magnets with excellent high-temperature magnetic properties are tailored. Hereby, the investigations in addition provide important clues to the evolution of the characteristic microstructural and magnetic properties and to the role of the involved elements.

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Phase formation and magnetic hardening mechanism of TbCu7 type Sm-Fe-N powders

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2018.01.071 ◽

2018 ◽

Vol 456 ◽

pp. 6-10

Author(s):

Cifu Lu ◽

Xiufeng Hong ◽

Zhiyi Ding ◽

Jiaxing Shi ◽

Xiaoqian Bao ◽

...

Keyword(s):

Phase Formation ◽

Hardening Mechanism ◽

Magnetic Hardening

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GRAIN TEXTURE, Nd CONTENT AND PROCESSING CONDITION EFFECTS ON MAGNETIC PROPERTIES OF NdFeB COMPOSITE MAGNETS

Modern Physics Letters B ◽

10.1142/s0217984913410261 ◽

2013 ◽

Vol 27 (19) ◽

pp. 1341026

Author(s):

XIAOYA LIU ◽

LIANXI HU ◽

YUPING LI ◽

TAIQING DENG

Keyword(s):

Magnetic Properties ◽

Annealing Time ◽

Processing Condition ◽

Grain Texture ◽

Hardening Mechanism ◽

Nanocomposite Magnet ◽

Energy Product ◽

Short Annealing ◽

Type Magnet ◽

Content Processing

The effects of grain texture, Nd content, processing conditions on magnetic properties and behavior of NdFeB nanocomposite magnet were investigated. The results demonstrate that mechanically activated disproportionation and desorption–recombination combined with plastic deformation process (M-HDDR & D) is an effective way to produce anisotropic NdFeB -type magnet. Magnetic anisotropy significantly enhances the magnetic properties of Nd 16 Fe 76 B 8 nanocomposite magnet, with the intrinsic coercivity (H ci ), magnetic induction (Br), and the energy product (BH) max achieving 0.88 T, 676.8 kA/m, and 135.2 kJ/m3, respectively. Decrease in Nd content improves the remanence but deteriorates the coercivity of NdFeB ternary composites. A low annealing temperature or short annealing time leads to an incomplete recombination, while a high temperature or long annealing time may result in grain overgrowth, and the optimum processing condition is found to be 780°C × 30 min. Pinning mechanism dominates in the magnetic hardening mechanism of Nd 16 Fe 76 B 8 composites prepared by both complete and incomplete recombination process, and particularly reversal nucleation process is also responsible for the latter case.

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Magnetic hardening mechanism study in FePt thin films

Journal of Applied Physics ◽

10.1063/1.369131 ◽

1999 ◽

Vol 85 (8) ◽

pp. 4886-4888 ◽

Cited By ~ 48

Author(s):

C. M. Kuo ◽

P. C. Kuo ◽

H. C. Wu ◽

Y. D. Yao ◽

C. H. Lin

Keyword(s):

Thin Films ◽

Mechanism Study ◽

Hardening Mechanism ◽

Magnetic Hardening ◽

Fept Thin Films

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Magnetic hardening mechanism of SmCo6.6Nb0.4 nanoflakes prepared by surfactant-assisted ball milling method

Journal of Applied Physics ◽

10.1063/1.4862221 ◽

2014 ◽

Vol 115 (17) ◽

pp. 17A713 ◽

Cited By ~ 5

Author(s):

Y. Q. Li ◽

M. Yue ◽

Q. Wu ◽

W. Q. Liu ◽

Y. Q. Liu ◽

...

Keyword(s):

Ball Milling ◽

Hardening Mechanism ◽

Milling Method ◽

Magnetic Hardening ◽

Surfactant Assisted

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Evolution of intrinsic coercivity in Pt-Co-B alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121417 ◽

1992 ◽

Vol 50 (1) ◽

pp. 202-203

Author(s):

N. Qiu

Keyword(s):

Permanent Magnets ◽

Ternary Alloys ◽

Good Thermal Stability ◽

Hardening Mechanism ◽

Potential Applications ◽

Magnetic Hardening ◽

Rapidly Solidification ◽

Evolution Of Microstructure ◽

Rapidly Solidified ◽

Thermal Stability Of

New permanent magnets based on Pt-Co-B ternary alloys have been developed by rapidly solidification with subsequent heat treatments. The coercivity achieved in the Pt-Co-B ternary alloys is more than double the highest coercivity observed in the Pt-Co binary system. Good thermal stability of the coercivity produced by annealing provides a basis for consolidation processes such as hot isotropic pressing to produce bulk magnets from the rapidly solidified Pt-Co-B materials. Increased coercivity coupled with special properties such as high Curie temperature, corrosion resistance and ductility may expand the potential applications for these alloys. The evolution of microstructure and its effect on coercivity from annealing the as-quenched materials are investigated to understand the magnetic hardening mechanism and optimize the magnetic properties.

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