Magnetic Hardening Mechanism in Re-Fe-B Permanent Magnets

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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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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Analysis of the magnetic hardening mechanism in RE-FeB permanent magnets

Journal of Magnetism and Magnetic Materials ◽

10.1016/0304-8853(88)90202-8 ◽

1988 ◽

Vol 74 (3) ◽

pp. 291-302 ◽

Cited By ~ 418

Author(s):

H. Kronmüller ◽

K.-D. Durst ◽

M. Sagawa

Keyword(s):

Permanent Magnets ◽

Hardening Mechanism ◽

Magnetic Hardening

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Magnetic hardening mechanism in sintered R–Fe–B permanent magnets

Journal of Materials Research ◽

10.1557/jmr.1988.0045 ◽

1988 ◽

Vol 3 (1) ◽

pp. 45-54 ◽

Cited By ~ 56

Author(s):

M. Sagawa ◽

S. Hirosawa

Keyword(s):

Temperature Dependence ◽

Permanent Magnets ◽

Spontaneous Magnetization ◽

Short Review ◽

Experimental Results ◽

Surface Conditions ◽

Hardening Mechanism ◽

Intrinsic Coercivity ◽

Field Coefficient ◽

Magnetic Hardening

After a short review on temperature dependence of the intrinsic coercivity in sintered Nd–Fe–B-type magnets 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 influence of the surface conditions of the sintered Nd–Fe–B magnets on the coercivity are reported. The results are interpreted in terms of the μoHc vs cμoHA – NIs plot, where Is is the spontaneous magnetization of R2Fe14B (R = Pr or Nd) and N is the effective demagnetization field coefficient.

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ChemInform Abstract: Magnetic Hardening Mechanism in Sintered Rare Earth-Iron-Boron Permanent Magnets

ChemInform ◽

10.1002/chin.198819342 ◽

1988 ◽

Vol 19 (19) ◽

Author(s):

M. SAGAWA ◽

S. HIROSAWA

Keyword(s):

Rare Earth ◽

Permanent Magnets ◽

Hardening Mechanism ◽

Magnetic Hardening

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Magnetic hardening of nanocrystalline Sm/sub 2/Fe/sub 15/Ga/sub 2/Zr/sub x/C/sub 2.2/ permanent magnets

IEEE International Magnetics Conference ◽

10.1109/intmag.1999.837856 ◽

1999 ◽

Author(s):

Jun-xian Zhang ◽

Zhao-hua Cheng ◽

D. Goll ◽

H. Kronmuller

Keyword(s):

Permanent Magnets ◽

Magnetic Hardening

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Magnetic hardening in iron‐neodymium‐boron permanent magnets

Journal of Applied Physics ◽

10.1063/1.334630 ◽

1985 ◽

Vol 57 (8) ◽

pp. 4097-4099 ◽

Cited By ~ 64

Author(s):

G. C. Hadjipanayis ◽

K. R. Lawless ◽

R. C. Dickerson

Keyword(s):

Permanent Magnets ◽

Magnetic Hardening

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Magnetic hardening mechanism in low-cobalt Fe-Cr-Co Alloys

10.1109/intmag.1990.734877 ◽

1990 ◽

Author(s):

J.J. Wyslocki ◽

J. Olszewski ◽

B. Wyslocki ◽

S. Szymura ◽

J. Wojcik

Keyword(s):

Hardening Mechanism ◽

Magnetic Hardening ◽

Co Alloys

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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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