The influence of particle size on the coercivity of sintered NdFeB magnets

Nothnagel, P.; Müller, K.‐H.; Eckert, D.; Handstein, A.

doi:10.1016/0304-8853(91)90786-a

Cited by 85 publications

(31 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previous investigations have shown experimentally that the coercivity can be enhanced by decreasing the average grain size [2][3][4]. Although coercivity increases with decreasing grain size within the range of 3.5-7.5 mm, there is a critical value below which the coercivity suddenly decreases with further grain refinement.…”

Section: Introductionmentioning

confidence: 94%

“…Although coercivity increases with decreasing grain size within the range of 3.5-7.5 mm, there is a critical value below which the coercivity suddenly decreases with further grain refinement. This critical value of the grain size is one order of magnitude larger than the single domain size of the Nd 2 Fe 14 B compound, and was reported to be related to the oxygen content in the magnet [2]. According to Christodoulou et al [5] refinement have not been thoroughly investigated, the origin of this coercivity decrease is still not clear.…”

Section: Introductionmentioning

confidence: 94%

See 1 more Smart Citation

The origin of coercivity decrease in fine grained Nd–Fe–B sintered magnets

Ohkubo

Hono

et al. 2009

Journal of Magnetism and Magnetic Materials

161

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 94%

Section: Introductionmentioning

confidence: 94%

The origin of coercivity decrease in fine grained Nd–Fe–B sintered magnets

Ohkubo

Hono

et al. 2009

Journal of Magnetism and Magnetic Materials

161

View full text Add to dashboard Cite

“…Many investigations have been carried out to improve the coercivity without using Dy, and an effective approach that involves refining the grain size of the Nd 2 Fe 14 B phase while retaining the thin continuous Nd-rich grain boundary (GB) phase has been found [4][5][6]. Previous studies have reported that the coercivity of sintered Nd-Fe-B magnets starts to deteriorate when the grain size falls below 3 lm [6,7]. The value of this grain size is one order of magnitude larger than the single domain size of the Nd 2 Fe 14 B phase.…”

Section: Introductionmentioning

confidence: 99%

Effect of Nd content on the microstructure and coercivity of hot-deformed Nd–Fe–B permanent magnets

et al. 2013

View full text Add to dashboard Cite

“…It is known experimentally that the coercivity of Nd-Fe-B permanent magnets increases by the reduction of the grain size following H c = a − blnD [8][9][10] . However, by the reduction of grain size below 3 µm, this relationship fails due to the oxidation of Nd-rich phases in ne-grained sintered magnets 11) .…”

Section: Effect Of Grain Size On Coercivity and Thermal Stability Of mentioning

confidence: 99%

Micromagnetic Simulations of Magnetization Reversals in Nd-Fe-B Based Permanent Magnets

2016

View full text Add to dashboard Cite

Finite element micromagnetic simulation was employed to explain how the microstructure of Nd-Fe-B permanent magnets such as grain size, grain shape, and grain boundary composition in uence the magnetization reversals and coercivity. Micromagnetic simulations showed that local demagnetization factor decreases as grain size decreases, which is attributed to a higher coercivity in ne-grained anisotropic permanent magnets. Lower demagnetization factor is also responsible for a lower temperature dependence of coercivity in the magnets with a smaller grain size. It was also found that the reduction of the magnetization of the grain boundary phase in hot-deformed Nd-Fe-B magnets leads to the coercivity enhancement due to a stronger pinning force against magnetic domain wall motion. The coercivity of Nd-Fe-B magnets cannot be enhanced by the reduction of the grain size alone unless the grain boundary phase become non-ferromagnetic, indicating that the role of the grain boundary phase is more pronounced in the Nd-Fe-B magnets with a smaller grain size.

show abstract

The influence of particle size on the coercivity of sintered NdFeB magnets

Cited by 85 publications

References 2 publications

The origin of coercivity decrease in fine grained Nd–Fe–B sintered magnets

The origin of coercivity decrease in fine grained Nd–Fe–B sintered magnets

Effect of Nd content on the microstructure and coercivity of hot-deformed Nd–Fe–B permanent magnets

Micromagnetic Simulations of Magnetization Reversals in Nd-Fe-B Based Permanent Magnets

Contact Info

Product

Resources

About