Sm2(Co, Cu, Fe, Zr)17 Magnets Having High iHc and (BH)max

Yoneyama, T.; Fukuno, A.; Ojima, T.

doi:10.1007/978-94-009-7825-6_81

Cited by 4 publications

(4 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[29,30] They obtained B r = 1.12 T, M H c = 0.6 MA/m, and (BH) max = 240.3 kJ/m 3 for an alloy corresponding to the nominal composition Sm(Co 0.674 Fe 0.213 Cu 0.100 Zr 0.013 ) 7.43 . Further refinement of the isothermal aging and step aging heat treatment [31] and compositional adjustment [32] yielded a permanent magnet with B r = 1.2 T, M H c = 1 MA/m, and (BH) max = 262.6 kJ/m 3 for the nominal composition Sm(Co 0.65 Fe 0.28 Cu 0.05 Zr 0.02 ) 7.67 . It is important to note that these magnets have a much better temperature coefficient of M H c than the Mn-and Cr-containing magnets, making them much more useful for elevated-temperature applications.…”

Section: Historical Review Of Development Of Sm-co Permanent Magnetsmentioning

confidence: 99%

“…In order to develop useful coercivity, extra Sm and considerable amounts (∼ 10 at.%) of Cu and Zr must be added and a complex and time-consuming heat treatment procedure must be applied. [26][27][28][29][30][31][32] The procedure consists of high-temperature sintering at ≥ 1200 • C for 1-3 h, a solid solution heat treatment at ∼ 1180 • C for 2-4 h, and a long-term isothermal aging at ∼ 800 • C for 20-50 h. Even after this long-term isothermal aging, the coercivity is still very low. As demonstrated in Fig.…”

Section: Nanograin Structure Nanocrystalline and Nanocomposite Sm-co ...mentioning

confidence: 99%

See 1 more Smart Citation

Sm–Co high-temperature permanent magnet materials

Liu

2019

Chinese Phys. B

View full text Add to dashboard Cite

Permanent magnets capable of reliably operating at high temperatures up to ∼ 450 • C are required in advanced power systems for future aircrafts, vehicles, and ships. Those operating temperatures are far beyond the capability of Nd-Fe-B magnets. Possessing high Curie temperature, Sm-Co based magnets are still very important because of their hightemperature capability, excellent thermal stability, and better corrosion resistance. The extensive research performed around the year 2000 resulted in a new class of Sm 2 (Co, Fe, Cu, Zr) 17 -type magnets capable of operating at high temperatures up to 550 • C. This paper gives a systematic review of the development of Sm-Co permanent magnets, from the crystal structures and phase diagrams to the intrinsic magnetic properties. An emphasis is placed on Sm 2 (Co, Fe, Cu, Zr) 17 -type magnets for operation at temperatures from 300 • C to 550 • C. The thermal stability issues, including instantaneous temperature coefficients of magnetic properties, are discussed in detail. The significance of nanograin structure, nanocrystalline, and nanocomposite Sm-Co magnet materials, and prospects of future rare-earth permanent magnets are also given.

show abstract

Section: Historical Review Of Development Of Sm-co Permanent Magnetsmentioning

confidence: 99%

Section: Nanograin Structure Nanocrystalline and Nanocomposite Sm-co ...mentioning

confidence: 99%

Sm–Co high-temperature permanent magnet materials

Liu

2019

Chinese Phys. B

View full text Add to dashboard Cite

show abstract

“…Fe v Cu x Z y ) Z sintered magnet containing relatively high Fe content, V > 0.28 (= 24.5 mol% Fe), and (BH) max as high as 264 kJ/m 3 has been obtained. 8,9) We focused on Sm 2 Co 17 sintered magnet containing a larger amount of Fe than in the magnets investigated previously. We have reported that high coercivity can be obtained for Sm(Co bal.…”

Section: Introductionmentioning

confidence: 99%

Effect of Pre-Aging Treatment on the Microstructure and Magnetic Properties of Sm(Co,Fe,Cu,Zr)<sub>7.8</sub> Sintered Magnets

et al. 2014

View full text Add to dashboard Cite

The effects of pre-aging treatment on the microstructure and magnetic properties of Sm(Co bal. Fe 0.35 Cu 0.06 Zr 0.02 ) 7.8 were investigated. The main phase of both solution-treated magnet and pre-aged magnet was the 1 : 7 phase, and there were no distinct differences between the X-ray diffraction profiles of these magnets. Fine Cu-rich precipitates a few tens of nanometers in size were observed in pre-aged magnet by scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy mapping, but such precipitates were not observed in solution-treated magnet. As for fully aged magnets, the cell size was smaller in pre-aged magnet than in non-pre-aged magnet. Thus, the pre-aging treatment gave a fine cellular structure. M r and H cJ of pre-aged magnet were almost same as those of non-pre-aged magnet. Squareness of the demagnetization curve for fully aged magnet was increased by pre-aging treatment. As a result, (BH) max of magnet subjected to pre-aging treatment was greater than that of magnet not subjected to pre-aging treatment. The fine cellular structure seemed to result in higher squareness. The following magnetic properties were obtained for Sm(Co bal. Fe 0.35 Cu 0.06 Zr 0.02 ) 7.8 by pre-aging treatment: M r = 1.24 T, H cJ = 1490 kA/m, and (BH) max = 266 kJ/m 3 .

show abstract

“…Previous studies showed that Zr is related to the structural modification and stabilization of the Sm 2 (Co, Fe) 17 phase [5][6][7]. It was reported that Zr addition not only increases the Cu and Sm solubility in the Sm 2 (Co, Fe) 17 phase at high temperature [8] but also enhances the anisotropy field [9]. Some studies also showed that higher Zr content can refine the microstructure and improve the coercivity [10][11][12].…”

Section: Introductionmentioning

confidence: 99%

Effect of Zr on the microstructure, magnetic domain structure, microchemistry and magnetic properties in Sm(Co_balCu_0.08Fe_0.10Zr_x)_8.5 magnets

Gong¹,

Gao²,

Feng³

et al. 2007

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

The effect of Zr on the microstructure, microchemistry and coercivity of Sm(CobalCu0.08Fe0. 10Zrx)8.5 (x = 0–0.10) magnets has been systematically investigated. The presence of Zr is responsible for the formation of the lamella structure. With increasing Zr content, a cellular-like structure gradually develops while the density of the lamella phase increases. A proper Zr content (0.015–0.060 at.%) is the key to form a complete and uniform cellular structure. Microchemistry data show that the Cu content in the cell boundaries in the magnet with 0.04 at.% Zr is higher than that with 0.015 at.% Zr, although both samples have similar microstructure morphologies. Higher coercivity is obtained in samples where the domain walls (DWs) are pinned at cell boundaries. For Zr-free or higher Zr samples, DWs nucleated at grain boundaries are responsible for the reduction in coercivity. During isothermal ageing, at a fixed Zr content, the coercivity is developed with increasing ageing time. These results clearly show that Zr plays an important role in the formation of a uniform cellular structure with the right microchemistry and that a critical amount of Zr is needed for the optimum magnetic properties.

show abstract

Sm2(Co, Cu, Fe, Zr)17 Magnets Having High iHc and (BH)max

Cited by 4 publications

References 1 publication

Sm–Co high-temperature permanent magnet materials

Sm–Co high-temperature permanent magnet materials

Effect of Pre-Aging Treatment on the Microstructure and Magnetic Properties of Sm(Co,Fe,Cu,Zr)<sub>7.8</sub> Sintered Magnets

Effect of Zr on the microstructure, magnetic domain structure, microchemistry and magnetic properties in Sm(Co_balCu_0.08Fe_0.10Zr_x)_8.5 magnets

Contact Info

Product

Resources

About

Sm2(Co, Cu, Fe, Zr)17 Magnets Having High iHc and (BH)max

Cited by 4 publications

References 1 publication

Sm–Co high-temperature permanent magnet materials

Sm–Co high-temperature permanent magnet materials

Effect of Pre-Aging Treatment on the Microstructure and Magnetic Properties of Sm(Co,Fe,Cu,Zr)<sub>7.8</sub> Sintered Magnets

Effect of Zr on the microstructure, magnetic domain structure, microchemistry and magnetic properties in Sm(CobalCu0.08Fe0.10Zrx)8.5 magnets

Contact Info

Product

Resources

About

Effect of Zr on the microstructure, magnetic domain structure, microchemistry and magnetic properties in Sm(Co_balCu_0.08Fe_0.10Zr_x)_8.5 magnets