Journal of Magnetism and Magnetic Materials最新文献_第3页

Phase stability and tunable structural, hyperfine, and magnetic properties of Sol–Gel FeNi nanoparticles 溶胶-凝胶FeNi纳米颗粒的相稳定性和可调结构、超细和磁性能

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-30 DOI: 10.1016/j.jmmm.2025.173792

M.A.R. Martinez , F.F.H. Aragón , L. León Félix , J. Mantilla , M.H. Sousa , M.C. Mathpal , J.F. Felix , J.A.H. Coaquira

In this study,

\sim

Fe₅₀Ni₅₀ powder alloys were synthesized successfully using the sol–gel method, followed by systematic thermal treatments up to 1000 °C in a reducing atmosphere (Ar-H

_{2}

). Synchrotron X-ray diffraction patterns indicate that the data are well modeled by face-centered cubic (FCC) FeNi phase. The stability of this phase was studied, revealing that as the temperature is increased, the unit cell volume changes, suggesting an enhancement in the migration of iron atoms. This migration alters the stoichiometry of the FeNi alloy, potentially shifting it beyond its nominal 50/50 composition. High-resolution TEM demonstrated the formation of the FeNi phase, which is in good agreement with the results obtained by XRD. Additionally, only a slight increase in crystalline particle size was observed. Magnetic characterization shows that thermal annealing strongly influences the magnetization. In particular, the sample annealed at 700 °C exhibits the highest magnetization and a Curie temperature

\sim

805 K, highlighting the role of thermal treatments in tuning the magnetic response. Zero-field cooling and field cooling measurements in the range 5–380 K further reveal irreversibilities above room temperature, attributed to the small particle size and strong interparticle interactions, which significantly affect the coercive field and overall magnetic behavior. These FeNi nanoparticles were characterized as magnetically soft materials. Mössbauer spectroscopy confirms the ferromagnetic behavior of the cubic FeNi phase as shown by XRD. Increasing the treatment temperature produces an increase in the hyperfine magnetic field, while the IS becomes more negative, which is primarily attributed to modifications in the s-electron density at the iron nuclei resulting from thermally induced electronic redistribution.

在本研究中，采用溶胶-凝胶法成功合成了~ Fe50Ni50粉末合金，然后在还原气氛（Ar-H2）中进行了高达1000°C的系统热处理。同步加速器x射线衍射图表明，面心立方（FCC） FeNi相能很好地模拟数据。研究了该相的稳定性，发现随着温度的升高，单位胞体积发生变化，表明铁原子的迁移增强。这种迁移改变了FeNi合金的化学计量，可能使其超出其标称的50/50组成。高分辨率透射电镜显示FeNi相的形成，这与XRD的结果吻合较好。此外，仅观察到晶体粒度略有增加。磁性表征表明，热退火对磁化强度有较大影响。特别是，在700°C退火的样品表现出最高的磁化强度和居里温度~ 805 K，突出了热处理在调节磁响应中的作用。在5-380 K范围内的零场冷却和场冷却测量进一步揭示了室温以上的不可逆性，这归因于小颗粒尺寸和强颗粒间相互作用，这显著影响了矫顽力场和整体磁行为。这些FeNi纳米颗粒被表征为磁性软材料。Mössbauer光谱分析证实了立方FeNi相的铁磁行为，如XRD所示。随着处理温度的升高，超细磁场增大，而IS变得更负，这主要是由于热诱导电子重分布导致铁核s电子密度的改变。

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引用次数: 0

Piezoelectric strain influenced modulation of magnetic domain wall motion in hybrid PMN-PT (011)/CoFeB heterostructures with perpendicular magnetic anisotropy 压电应变对垂直磁各向异性PMN-PT (011)/CoFeB杂化异质结构磁畴壁运动调制的影响

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-30 DOI: 10.1016/j.jmmm.2025.173796

S. Roy , A. Solignac , N. Montblanc , T. Maroutian , A. Di Pietro , D. Ravelosona , G. Durin , L. Herrera Diez , G. Agnus

This study investigates how piezoelectric strain influences magnetic domain-wall (DW) motion in perpendicularly magnetized Ta/CoFeB/MgO ultrathin films grown on PMN-PT (011) substrates. Applying a gate voltage along the out-of-plane direction of the PMN-PT (011) substrate induces a non-volatile electrical polarization, producing a stable strain state (the poled state), which was confirmed using piezoresponse force microscopy. In this configuration, polar magneto-optical Kerr effect (P-MOKE) measurements reveal that this voltage-controlled remanent strain in the PMN-PT substrate can modulate DW dynamics and magnetic properties relative to the unpoled (as-grown) state. This response can be linked not only to a strain-controlled magnetic anisotropy but also to a strain-controlled change in the homogeneity of the magnetic landscape. The multiple polarization directions of the domains in the unpoled state of the PMN-PT can result in a wider anisotropy distribution in the magnetic system compared to the poled state. This can significantly affect DW nucleation/depinning fields, highlighting the role of piezoelectric strain in controlling DW dynamics. These results are of interest for the development of DW based magnetic memory applications with a reduced energy consumption.

本文研究了压电应变如何影响在PMN-PT（011）衬底上生长的垂直磁化Ta/CoFeB/MgO超薄膜的磁畴壁运动。在PMN-PT（011）衬底的面外方向施加栅极电压可诱导非易失性电极化，产生稳定的应变状态（极化状态），并通过压电响应力显微镜证实了这一点。在这种结构下，极性磁光克尔效应（P-MOKE）测量表明，PMN-PT衬底中的电压控制残余应变可以调制相对于未极化（生长）状态的DW动力学和磁性能。这种响应不仅与应变控制的磁各向异性有关，而且与应变控制的磁景观均匀性变化有关。PMN-PT在非极性状态下畴的多个极化方向导致磁系统的各向异性分布比极性状态更宽。这可以显著影响DW成核/脱屑场，突出了压电应变在控制DW动力学中的作用。这些结果对于开发基于DW的低能耗磁存储应用具有重要意义。

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引用次数: 0

Investigation of loss and noise in toroidal core current sensors 环形铁芯电流传感器损耗与噪声的研究

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-30 DOI: 10.1016/j.jmmm.2025.173788

Tingting Fan , Lizi Pan , Chenbo Zhao, Qingfang Liu, Jianbo Wang

Cobalt-based amorphous toroidal core are used to fabricate a giant magneto impedance current sensor in this work. By adjusting the bias current, a high sensitivity of 31.6 V/A is obtained, which can realize weak current detection. The core losses are then measured and calculated to analyze the noise level. The results shows that the core loss characteristics dominate the sensor's noise, besides that, the excitation current and DC bias current also affect the noise performance. Based on optimized parameters, a current threshold alarm is realized, achieving current threshold detection and alarm functionality. This study provides theoretical and experimental guidance for low-noise design optimization in current sensing.

本文采用钴基非晶环形磁芯制作巨磁阻电流传感器。通过调节偏置电流，获得31.6 V/ a的高灵敏度，可实现微弱电流检测。然后测量和计算磁芯损耗以分析噪声水平。结果表明，铁芯损耗特性是传感器噪声的主要影响因素，此外，励磁电流和直流偏置电流也影响传感器的噪声性能。根据优化后的参数，实现电流阈值告警，实现电流阈值检测和告警功能。该研究为电流传感的低噪声优化设计提供了理论和实验指导。

引用次数: 0

Inducing and/or redirecting magnetic anisotropy in Co films with collapsed hard-magnetization axes 硬磁化轴塌陷的Co薄膜中磁各向异性的诱导和/或重定向

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-30 DOI: 10.1016/j.jmmm.2025.173805

L.F.S. Azeredo , H.S. Acosta , A.M.H. de Andrade , J. Geshev

Magnetic anisotropy is a key characteristic of magnetic materials and is a prerequisite for magnetic hysteresis. In thin magnetic films, it is usually induced by applying magnetic field either during growth or in the course of a post-deposition treatment. This study presents a comparative study of different methods — in-field sputtering deposition, annealing and ion irradiation — for inducing uniaxial magnetic anisotropy and even changing its easy-magnetization direction in polycrystalline Co films presenting collapsed hard-magnetization axes. The latter stands for the presence of prominent peaks in the angular variations of the remanent magnetization and coercivity centered ninety degrees off of the easy axis. The advantages, disadvantages and limitations of the three different techniques used to induce magnetic anisotropy are evaluated and discussed.

磁各向异性是磁性材料的一个重要特性，也是磁滞的先决条件。在磁性薄膜中，它通常是在生长过程中或在沉积后处理过程中通过施加磁场引起的。本研究对比研究了在硬磁化轴坍塌的多晶Co薄膜中，采用场内溅射沉积、退火和离子辐照等不同方法诱导单轴磁各向异性，甚至改变其易磁化方向。后者表示在剩余磁化强度和矫顽力的角变化中存在显著的峰值，其中心距易轴90度。对三种不同磁各向异性诱导技术的优缺点和局限性进行了评价和讨论。

引用次数: 0

Alloying effect on the magnetic and magnonic properties of a thin-film superlattice based on the magnetic semiconductor Ge1−xFex/Ge 合金化对基于磁性半导体Ge1−xFex/Ge的薄膜超晶格磁性和磁能谱的影响

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-29 DOI: 10.1016/j.jmmm.2025.173787

Marouan Karam, Atika Fahmi, Ahmed Qachaou, Mounir Fahoume, Ismail Benaicha, Jaouad Mhalla, Abderrahim Raidou, Mohamed Lharch

In this work, we investigate the effect of alloying on the magnetic properties of the semiconductor ferromagnetic Ge

_{1 - x}

Fe

_{x}

/Ge(001) superlattice. The system Hamiltonian is described within the localized-spin Heisenberg model. The excitation spectrum is calculated using linear spin-wave theory. A quantitative analysis of the experimental magnetization data reveals the existence of a spin reorientation transition (SRT) at the inflection temperature (

T = T_{r}

). To explain the behavior of this magnetization, we have developed a theoretical model based on the presence of a mixture of two magnon populations: quantum magnons and classical magnons. Furthermore, the agreement between the calculated and experimental magnetization curves is very satisfactory, enabling the determination of the key magnetic parameters of the system, namely,

J_{∥} (x)

,

J_{⊥} (x)

,

Δ (x)

, and

T_{r} (x)

.

在这项工作中，我们研究了合金对半导体铁磁Ge1−xFex/Ge（001）超晶格磁性能的影响。在局域自旋海森堡模型中描述了系统的哈密顿量。利用线性自旋波理论计算激发谱。对实验磁化数据的定量分析表明，在弯曲温度（T=Tr）下存在自旋重取向跃迁（SRT）。为了解释这种磁化行为，我们建立了一个基于两种磁振子种群混合物存在的理论模型：量子磁振子和经典磁振子。此外，计算和实验磁化曲线之间的一致性非常令人满意，从而可以确定系统的关键磁参数，即J∥(x), J⊥(x)， Δ(x)和Tr(x)。

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引用次数: 0

Optimizing Nd–Ce–Fe–B grain boundary structure by Pr–Nd–Cu–Ga prealloyed powder to enhance coercivity 用Pr-Nd-Cu-Ga预合金粉优化Nd-Ce-Fe-B晶界结构，提高矫顽力

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-29 DOI: 10.1016/j.jmmm.2025.173790

Zikai Wu , Hongsheng Chen , Zhongge Luo , Chen Wang , Jiayi He , Kuangxin Luo , Haojun Zhou , Fenghua Luo

Cerium (Ce) is a high-quality substitute for Pr/Nd in Nd–Fe–B magnets due to its low cost and abundant natural reserves. However, the coercivity (H_cj) of Re–Fe–B magnets with high Ce content is difficult to improve due to the aggregation of ReFe₂ phase at the triple junctions. This study investigated the grain boundary reconstruction in Nd-Ce-Fe-B sintered magnets using Pr–Nd–Cu–Ga prealloyed powder. The results indicate that as the addition amount of Pr–Nd–Cu–Ga increases, H_cj gradually increases. When the addition amount is 4 wt%, the maximum H_cj of the obtained magnet at a remanence of 11.5 kGs is 14.8 kOe. Grain boundary reconstruction promotes the continuous formation of ReFe₂ and other rare earth rich phases at grain boundaries, promoting the forming of thicker grain boundary layers and improving magnetic isolation. Furthermore, Pr–Nd–Cu–Ga leads to an increase in ReFe₂ phase; Cu and Ga can enhance the stability of ReFe₂ phase, while Nd partially replaces Ce in the grain boundary ReFe₂ phase, forming a new Nd–dominated 1:2 phase that enhances magnet wettability. The results advance the understanding of the ReFe₂ phase and provide critical insights for developing low–cost Nd–Ce–Fe–B magnets with high H_cj.

铈（Ce）成本低，储量丰富，是钕铁硼磁体中Pr/Nd的优质替代品。然而，高Ce含量Re-Fe-B磁体的矫顽力（Hcj）由于ReFe2相在三结处聚集而难以提高。本文研究了用Pr-Nd-Cu-Ga预合金粉末对Nd-Ce-Fe-B烧结磁体的晶界重建。结果表明，随着Pr-Nd-Cu-Ga添加量的增加，Hcj逐渐增大。当添加量为4 wt%时，所得磁体在残余量为11.5 kg时的最大Hcj为14.8 kOe。晶界重构促进了ReFe2等富稀土相在晶界处的不断形成，促进了更厚的晶界层的形成，提高了磁隔离度。此外，Pr-Nd-Cu-Ga导致ReFe2相增加；Cu和Ga增强了ReFe2相的稳定性，而Nd部分取代了晶界ReFe2相中的Ce，形成以Nd为主的1:2相，增强了磁体的润湿性。研究结果促进了对ReFe2相的理解，并为开发低成本高Hcj的Nd-Ce-Fe-B磁体提供了重要见解。

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引用次数: 0

Investigation of magnetic phase transition and critical behavior in Cu2OSeO3 via magnetocaloric effect 利用磁热效应研究Cu2OSeO3的磁相变及临界行为

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-29 DOI: 10.1016/j.jmmm.2025.173791

Sudipta Mahana , Prasanta Kumar Behera , Keshab Chandra Prusty , Pronoy Nandi , Dinesh Topwal

Polycrystalline Cu₂OSeO₃ was synthesized via a solid-state reaction method, and its phase purity was confirmed through X-ray diffraction followed by Rietveld refinement. The compound features two distinct crystallographic copper sites: Cu(I) in a trigonal bipyramidal configuration and Cu(II) in a square pyramidal arrangement, present in a 1:3 ratio. This unique structure leads to complex magnetic interactions between the sites. Magnetic properties were investigated using DC magnetization and AC susceptibility measurements. The material exhibits a delicate balance of symmetric superexchange interactions, antisymmetric Dzyaloshinskii-Moriya (DM) interaction, magnetocrystalline anisotropy, and Zeeman energy, resulting in various intricate magnetic phases. These include fluctuation disorder (FD), helical, skyrmion mixed conical and tilted spiral, conical, field-polarized ferrimagnetism, and importantly, the skyrmion phase. Additionally, the magnetocaloric effect was studied through temperature-dependent heat capacity measurements under different magnetic fields. The findings indicate reasonable magnetic refrigeration capabilities, with maximum magnetic entropy changes of 2.23 J/kg·K and 4.25 J/kg·K at around 60 K for field changes of 4 T and 7 T, respectively. The corresponding maximum relative cooling powers are determined to be 67 J/Kg and 140 J/kg. The critical correlation was also investigated through the magnetocaloric effect, demonstrating 3D Heisenberg interaction above the paramagnetic to FD transition temperature (T_c), accompanied by short-range magnetic correlations. Furthermore, the universal behavior of the normalized magnetic entropy-change curve confirms the presence of a second-order magnetic phase transition near T_c under high magnetic fields.

采用固相反应法制备了多晶Cu2OSeO3，并通过x射线衍射和Rietveld精馏确定了其相纯度。该化合物具有两个不同的晶体铜位：Cu(I)在三角形双锥体结构中，Cu（II）在正方形锥体结构中，以1:3的比例存在。这种独特的结构导致了位点之间复杂的磁相互作用。通过直流磁化和交流磁化率测试研究了材料的磁性能。该材料表现出对称超交换相互作用、反对称Dzyaloshinskii-Moriya （DM）相互作用、磁晶各向异性和塞曼能量的微妙平衡，导致各种复杂的磁相。其中包括涨落无序态（FD）、螺旋态、斯基米子混合锥形和倾斜螺旋态、锥形态、场极化铁磁态，以及重要的斯基米子相。此外，通过测量不同磁场下的温度相关热容，研究了磁热效应。结果表明，在磁场变化为4 T和7 T时，在60 K左右，磁熵变化最大，分别为2.23 J/kg·K和4.25 J/kg·K。相应的最大相对冷却功率分别为67 J/Kg和140 J/Kg。通过磁热效应研究了临界相关性，证明了顺磁到FD转变温度（Tc）以上的三维海森堡相互作用，并伴有短程磁相关性。此外，归一化磁熵变曲线的普遍行为证实了高磁场下Tc附近存在二阶磁相变。

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引用次数: 0

The influence of quenching temperature on the high-temperature properties and microstructure of FeNiCo alloys 淬火温度对FeNiCo合金高温性能和显微组织的影响

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-29 DOI: 10.1016/j.jmmm.2025.173794

Dongliang Guo , Xinteng Shen , Xiangtao Yu , Min Lin , Yingli Sun , Yong Ding , Aru Yan

The effects of quenching temperature (800–1000 °C) on the key properties of Fe₆₁Ni₃₂Co₇ low-expansion alloy are investigated, which reveals that quenching temperature significantly regulates the alloy's grain size and performance. The core findings indicate that the alloy achieves a synergistic optimization of high-temperature soft magnetic properties and low expansion characteristics under a quenching temperature of 950 °C. At this temperature, the alloy exhibits excellent overall soft magnetic performance at 200 °C: saturated magnetic flux density rises markedly to 973.7mT, maximum permeability increases dramatically (about 5.6 times higher than the original state), and coercivity is significantly reduced by 85%. Notably, the coefficient of thermal expansion in this optimized state remains at a low level (2.199 × 10⁻⁶/°C). The performance enhancement mechanism mainly stems from the full release of residual stress induced by quenching (recrystallized region >94%), optimization of magnetic domain structure (reduction of domain wall energy) and the effect of high Curie temperature in extending the temperature range for magnetostriction. This research provides crucial process guidance for the development of FeNiCo alloys with excellent high-temperature soft magnetic properties and stable low-expansion characteristics, which contributes to precision instruments and high-sensitivity sensors that require stringent thermal and magnetic stability.

研究了淬火温度（800 ~ 1000℃）对Fe61Ni32Co7低膨胀合金关键性能的影响，发现淬火温度对合金的晶粒尺寸和性能有显著调节作用。结果表明，该合金在950℃的淬火温度下实现了高温软磁性能和低膨胀性能的协同优化。在此温度下，合金在200℃时表现出优异的整体软磁性能：饱和磁通密度显著上升至973.7mT，最大磁导率显著提高（约为原始状态的5.6倍），矫顽力显著降低85%。值得注意的是，该优化状态下的热膨胀系数保持在较低的水平（2.199 × 10−26 /°C）。其性能增强机制主要源于淬火残余应力的充分释放（再结晶区>；94%）、磁畴结构的优化（畴壁能的降低）以及高居里温度对磁致伸缩温度范围的影响。该研究为开发具有优异高温软磁性能和稳定低膨胀特性的FeNiCo合金提供了重要的工艺指导，有助于对热稳定性和磁稳定性要求严格的精密仪器和高灵敏度传感器。

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引用次数: 0

Magnetic phase transition and magnetocaloric effect in rare-earth-free high entropy alloys MnCoNiFeCu 无稀土高熵合金MnCoNiFeCu的磁相变和磁热效应

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-29 DOI: 10.1016/j.jmmm.2025.173793

Yulin Pan, Yong Li

In this paper, the structural characteristics, magnetic properties and magnetocaloric performance of a series of high-entropy alloys (HEAs) Mn₂₀Co₂₀Ni₂₀Fe_26+xCu_14-x (x = 0, 2, 4) have been experimentally determined and theoretically analyzed. The results showed that these alloys have a disordered FCC crystal structure. The Fe concentration determines the temperature range within which the ferromagnetic behavior and Curie temperatures can be adjusted. In particular, it decreases from 274 K for Fe₂₆Cu₁₄ to 242 K for Fe₃₀Cu₁₀. In addition, the maximum magnetic entropy change values are obtained in the magnetic field change of 7 T for 1.37, 1.28 and 1.33 J/kgK were obtained for x = 0, 2 and 4, respectively. Compared to other transition metal-based high-entropy alloys reported in the literatures, the present material shows comparable or superior performance. The experimental characterization results are in good agreement with the theoretical predictions and affords an extensive series of rare-earth-free HEAs exhibiting pronounced magnetocaloric properties.

本文对Mn20Co20Ni20Fe26+xCu14-x （x = 0,2,4）系列高熵合金（HEAs）的结构特征、磁性能和磁热性能进行了实验测定和理论分析。结果表明，这些合金具有无序的FCC晶体结构。铁浓度决定了铁磁行为和居里温度可调节的温度范围。特别是Fe26Cu14的274k， Fe30Cu10的242k。另外，在7 T磁场变化时，x = 0、2和4时的最大磁熵变化值分别为1.37、1.28和1.33 J/kgK。与文献报道的其他过渡金属基高熵合金相比，本材料表现出相当或更好的性能。实验表征结果与理论预测很好地吻合，并提供了一系列具有明显磁热特性的无稀土HEAs。

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引用次数: 0

Effect of cooling rate on the microstructure and magnetic properties of melt-spun CeFeB ribbons 冷却速率对熔体纺CeFeB带状组织和磁性能的影响

IF 3 3区材料科学 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Magnetism and Magnetic Materials

Pub Date : 2025-12-28 DOI: 10.1016/j.jmmm.2025.173785

Yasin Yılmaz , Muhammed Fatih Kılıçaslan

NdFeB permanent magnetic alloys are widely used in industrial applications, particularly in electronics, due to their excellent magnetic performance. However, their dependence on expensive rare earth and neodymium elements has led to supply risks and price instability. As a more abundant and economical alternative, CeFeB alloys have gained attention recently. In this study, CeFeB ribbons with a nominal composition of Ce₃₅Fe₆₄B₁ (wt%) were fabricated via melt spinning method at different wheel surface speeds (3–35 m/s). XRD analysis revealed that all of the ribbon samples exhibit partially crystalline structures. They contains the Ce₂Fe₁₄B hard magnetic phase, along with soft magnetic α-Fe and paramagnetic CeFe₂ phases. As the wheel surface speed increased, crystallite size of the Ce₂Fe₁₄B phase reduced, and tendency to amorphous phase formation increased. The finest crystallite size of the Ce₂Fe₁₄B phase of 26.18 nm was achieved at the wheel surface speed of 5 m/s. Accordingly, the optimum magnetic properties were obtained. These are the coercivity, remanence, maximum energy product, and remanence ratio of 4301.84 Oe, 62.12 emu/g, 10.94 MGOe, and 0.624, respectively. These results highlight the critical role of cooling rate for modifying the microstructure and improving the magnetic performance. This study shows that the CeFeB alloys posses the requisite magnetic performance to serve as competitive, low-cost alternatives to their NdFeB counterparts. Their favorable characteristics highlight a strong potential for integration into large-scale industrial systems where rare earth scarcity and economic viability are of primary concern.

钕铁硼永磁合金由于其优异的磁性而广泛应用于工业领域，特别是电子领域。然而，它们对昂贵的稀土和钕元素的依赖导致了供应风险和价格不稳定。CeFeB合金作为一种储量丰富、经济实惠的替代材料，近年来备受关注。在本研究中，标称成分为Ce₃₅Fe₆₄B₁（wt%）的CeFeB缎带通过熔体纺丝法在不同车轮表面速度（3-35 m/s）下制成。XRD分析表明，所有带状样品均呈现部分结晶结构。它们含有Ce₂Fe₁₄B硬磁相，以及软磁α-Fe和顺磁CeFe₂相。随着车轮表面速度的增加，Ce₂Fe₁₄B相的晶粒尺寸减小，形成非晶相的倾向增加。当砂轮表面速度为5 m/s时，Ce₂Fe₁₄B相的晶粒尺寸为26.18 nm。从而获得了最佳的磁性能。矫顽力为4301.84 Oe，剩余物为62.12 emu/g，最大能积为10.94 MGOe，剩余物比为0.624。这些结果强调了冷却速度对改变微观结构和提高磁性能的关键作用。这项研究表明，CeFeB合金具有必要的磁性，可以作为其NdFeB同类产品的竞争性低成本替代品。它们的有利特点突出了融入大型工业系统的强大潜力，在这些系统中，稀土稀缺和经济可行性是主要关注的问题。

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引用次数: 0