Journal of Magnetism and Magnetic Materials最新文献_第8页

A system generating an impulse magnetic field with a closed magnetic circuit and a thyristor as a switching element 用闭合磁路和可控硅作为开关元件产生脉冲磁场的系统

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-26 DOI: 10.1016/j.jmmm.2025.173003

Andrzej Skumiel , Rafał M. Wojciechowski

引用次数: 0

Analysis of the influence mechanism of CeFe2 phase on coercivity in high-performance Nd-Ce-Fe-B diffusion magnets CeFe2相对高性能Nd-Ce-Fe-B扩散磁体矫顽力的影响机理分析

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-25 DOI: 10.1016/j.jmmm.2025.173001

Yuan Qin , Xiangming Wang , Lele Zhang , Min Fan , Jie Song , Gang Wang , Weiqiang Liu , Hao Chen , Penghao Yue , Zhibo Zhao , Zhanjia Wang , Yuqing Li , Ming Yue

{"title":"Analysis of the influence mechanism of CeFe2 phase on coercivity in high-performance Nd-Ce-Fe-B diffusion magnets","authors":"Yuan Qin , Xiangming Wang , Lele Zhang , Min Fan , Jie Song , Gang Wang , Weiqiang Liu , Hao Chen , Penghao Yue , Zhibo Zhao , Zhanjia Wang , Yuqing Li , Ming Yue","doi":"10.1016/j.jmmm.2025.173001","DOIUrl":"10.1016/j.jmmm.2025.173001","url":null,"abstract":"<div><div>In this study, we have prepared high-performance (Nd, Ce)-Fe-B magnets with 16.95 wt% and 23.73 wt% Ce / total rare earth (TRE) content, as well as Dy diffusion magnets. The concern between the CeFe<sub>2</sub> phase, microstructure, and coercivity of the magnets was clarified. When the Ce / TRE content increased to 23.73 wt%, a little of the CeFe<sub>2</sub> phase appeared in the magnet, which improved the fluidity of the liquid phase, promoted the formation of grain boundary phases (GBs), and optimized the microstructure. Therefore, when the GBs thickness increased to 6.39 nm, the coercivity slightly increased. However, in the subsequent heavy rare earth grain boundary diffusion, the coercivity increment (Δ<em>H</em><sub>cj</sub>) of the magnet with the CeFe<sub>2</sub> phase was 2.96 kOe, lower than the 4.68 kOe in the magnet without the CeFe<sub>2</sub> phase. From theoretical calculations and experimental results, the diffusion channel of the Dy elements was blocked by the CeFe<sub>2</sub> phase, and the Dy atom would enter the CeFe<sub>2</sub> phase to form the (Ce, Dy)Fe<sub>2</sub> phase. Therefore, the presence of the CeFe<sub>2</sub> phase led to a smaller diffusion depth of Dy elements, less core–shell structure of the main phase, lower effective Dy utilization rate, and lower Δ<em>H</em><sub>cj</sub>.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"623 ","pages":"Article 173001"},"PeriodicalIF":2.5,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143726302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental estimation of the remanent induction for the study of functional fatigue in permanent magnets 永磁体功能疲劳研究中剩余感应的实验估计

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-25 DOI: 10.1016/j.jmmm.2025.172965

Abderraouf Ouazib , Mathieu Domenjoud , Laurent Daniel

{"title":"Experimental estimation of the remanent induction for the study of functional fatigue in permanent magnets","authors":"Abderraouf Ouazib , Mathieu Domenjoud , Laurent Daniel","doi":"10.1016/j.jmmm.2025.172965","DOIUrl":"10.1016/j.jmmm.2025.172965","url":null,"abstract":"<div><div>The magnetization of new generation hard ferromagnetic materials is difficult to access experimentally without the use of advanced and expensive instruments. This article proposes two novel, easily implementable techniques for measuring the remanent induction of permanent magnets: a variant of the extraction method and a residual magnetic field method. Both methods are validated on hard Ferrites by comparison with hysteresis loop measurements taken as a reference measurement. The advantages and disadvantages of each method are discussed. Subsequently, the proposed techniques are applied to measure the remanent induction of rare-earth magnets, specifically Neodymium–Iron–Boron (Nd<img>Fe<img>B) and Samarium-Cobalt (Sm-Co). The obtained results exhibit consistency with manufacturer-provided data, attesting to the accuracy of the proposed measurement methodologies. Furthermore, the research investigates the effect of cyclic mechanical loading on the remanent induction of permanent magnets. The magnets are subjected to a set of 10<sup>6</sup> sinusoidal uniaxial compression cycles at a frequency of 30 Hz and at stress amplitudes representative for practical conditions in electrical machine applications. The remanent induction of the mechanically cycled magnets is subsequently measured. The investigation reveals no significant fatigue effect on the remanent induction in the studied hard materials. Overall, this study provides insights into the magneto-mechanical coupling effects in hard ferromagnetic materials and into the performance analysis of magnet properties under time-varying mechanical loadings.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"623 ","pages":"Article 172965"},"PeriodicalIF":2.5,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Critical behavior and anisotropic magnetocaloric effect in off-stoichiometric van der Waals ferromagnet Fe3-xGaTe2 非化学计量范德华铁磁体Fe3-xGaTe2的临界行为和各向异性磁热效应

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-24 DOI: 10.1016/j.jmmm.2025.172997

Yurong You , Jun Liu , Bei Ding , Feng Xu , ZhengMing Sun

{"title":"Critical behavior and anisotropic magnetocaloric effect in off-stoichiometric van der Waals ferromagnet Fe3-xGaTe2","authors":"Yurong You , Jun Liu , Bei Ding , Feng Xu , ZhengMing Sun","doi":"10.1016/j.jmmm.2025.172997","DOIUrl":"10.1016/j.jmmm.2025.172997","url":null,"abstract":"<div><div>The evolution of magnetic interactions, critical properties and magnetocaloric effects of off-stoichiometric room-temperature van der Waals Fe<sub>3-</sub><em><sub>x</sub></em>GaTe<sub>2</sub> are systematically investigated. Density functional theory (DFT) calculations reveal that the ferromagnetic exchange interactions between different Fe atoms play an important role in magnetic couplings and the change of Curie temperature <em>T<sub>C</sub></em>. Moreover, the Fe vacancy in different sites can also significantly affect the <em>T<sub>C</sub></em>. For Fe<sub>2.72</sub>GaTe<sub>2.01</sub> single crystal, the critical exponents <em>β</em> of 0.474(3) and <em>γ</em> of 1.018(9) with <em>T<sub>C</sub></em> at 336.7 K are obtained by the modified Arrott plot, whereas the critical exponent <em>δ</em> of 2.72(1) is yielded from a critical isotherm analysis at <em>T<sub>C</sub></em>. The results of these critical exponents indicate that off-stoichiometric Fe<sub>2.72</sub>GaTe<sub>2.01</sub> shows an approximate mean-field critical behavior. Furthermore, the exchange interaction distance decays as <em>J ≈ r<sup>-4.53</sup></em> proving the long-range ferromagnetism. In addition, the single crystal exhibits an anisotropic magnetocaloric behavior. The maximal value of the magnetic entropy change <em>ΔS<sub>m</sub></em> reaches -1.7 (-1.0) J kg<sup>-1</sup>K<sup>−1</sup> for a magnetic field change of 50 kOe in H//<em>c</em> axis (H//<em>ab</em> plane). Based on the field dependent <em>ΔS<sub>m</sub></em>, the calculated critical exponent <em>n</em> is less than 2 at around <em>T<sub>C</sub></em>, confirming a second-order type of the magnetic transition and reliability of the obtained critical exponents.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"623 ","pages":"Article 172997"},"PeriodicalIF":2.5,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143726303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Role of dextran decomposition process on the magnetite nanoparticles crystallization and magnetic hyperthermia effect 葡聚糖分解过程对磁铁矿纳米颗粒结晶和磁热疗效果的影响

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-24 DOI: 10.1016/j.jmmm.2025.172999

Agnieszka Ciuraszkiewicz , Łukasz Hawełek , Piotr Gębara , Tymon Warski , Katarzyna Stan-Głowińska , Dariusz Łukowiec , Aleksandra Kolano-Burian , Joanna Wojewoda-Budka , Adrian Radoń

{"title":"Role of dextran decomposition process on the magnetite nanoparticles crystallization and magnetic hyperthermia effect","authors":"Agnieszka Ciuraszkiewicz , Łukasz Hawełek , Piotr Gębara , Tymon Warski , Katarzyna Stan-Głowińska , Dariusz Łukowiec , Aleksandra Kolano-Burian , Joanna Wojewoda-Budka , Adrian Radoń","doi":"10.1016/j.jmmm.2025.172999","DOIUrl":"10.1016/j.jmmm.2025.172999","url":null,"abstract":"<div><div>Magnetite nanoparticles (MNPs) are constantly studied in various biomedical applications, including magnetically-induced hyperthermia. This study tested the role of the dextran decomposition process on the MNPs crystallization and magnetic hyperthermia effect. It was confirmed that the modification of the synthesis method (medium and the procedure of the dextran introduction) results in the synthesis of magnetite nanoparticles with an average crystallite size from 3.88 ± 1.38 to 45.97 ± 0.76 nm and different magnetic properties. It was possible to synthesize nanoparticles with superparamagnetic properties (magnetization of 54.26 emu g<sup>−1</sup> and coercivity of 0.36 Oe) as well as a sample with a higher coercivity equal to 19.26 Oe and magnetization equal to 51.35 emu g<sup>−1</sup>. The changes in the structure, morphology, and magnetic properties reflect the applicability potential of the magnetite nanoparticles in magnetic hyperthermia. The highest effect was observed for the sample synthesized in benzyl ether in the presence of dextran 40000. For a concentration of 0.25 mg ml<sup>−1</sup>, the specific absorption rate (SAR) was even higher than 200 W g<sup>−1</sup>. However, as shown, the SAR parameter is insufficient to analyze the applicability potential, and the temperature increase must be consequently analyzed. For a concentration of 0.25 mg ml<sup>−1</sup>, the temperature change was equal to 8.83 ± 1.03℃, while for 2 mg ml<sup>−1</sup> to 21.20 ± 0.83 ℃.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"623 ","pages":"Article 172999"},"PeriodicalIF":2.5,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143726301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Automatic eigenvalue method in micromagnetic and atomistic simulations 微磁和原子模拟中的自动特征值方法

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-24 DOI: 10.1016/j.jmmm.2025.172989

Xintao Fan , Shichao Zhang , Weiwei Wang , Lingyao Kong , Youmin Guo , Yizhou Liu , Haifeng Du

引用次数: 0

Spin-reorientation and phase diagram for a ferrimagnet with compensation point in inclined magnetic field 倾斜磁场中带补偿点的铁氧体的自旋定向和相位图

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-22 DOI: 10.1016/j.jmmm.2025.172968

D.O. Ignatyeva , N.A. Gusev , A.K. Zvezdin , V.I. Belotelov

引用次数: 0

New effective field theory in a cluster with n-sites correlating with n-free spins: Ferrimagnetic and Antiferromagnetic 与n-自由自旋相关的n位团簇的新有效场论：铁磁和反铁磁

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-22 DOI: 10.1016/j.jmmm.2025.172967

Jander P. Santos , Wagner S. Machado , Cássio L. Nunes , Ümit Akıncı

{"title":"New effective field theory in a cluster with n-sites correlating with n-free spins: Ferrimagnetic and Antiferromagnetic","authors":"Jander P. Santos , Wagner S. Machado , Cássio L. Nunes , Ümit Akıncı","doi":"10.1016/j.jmmm.2025.172967","DOIUrl":"10.1016/j.jmmm.2025.172967","url":null,"abstract":"<div><div>The Ising model is a central tool in the study of spin systems, with various generalizations to describe complex magnetic orderings. This work proposes a new application of the effective field theory (EFT) using clusters with <span><math><mi>n</mi></math></span>-sites, extending previous approaches to ferrimagnetic and antiferromagnetic states. Two specific cases are analyzed: a three-layer system of triangular lattices for ferrimagnetism and a square lattice for antiferromagnetism. The results include magnetizations, magnetic susceptibilities, and phase diagrams, showing that increasing the number of sites in the cluster improves accuracy, bringing the values closer to those obtained from Monte Carlo simulations. The proposed approach offers an efficient tool to study magnetic systems with different couplings and structural configurations. Although the new method presents improvements in numerical results, it is important to emphasize that its main contribution lies in introducing a more efficient approach, with simplifications in mathematical expansions aimed at reducing the computational time required in studies of this nature.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"622 ","pages":"Article 172967"},"PeriodicalIF":2.5,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electromechanical control of spin-Seebeck effects in armchair graphene nanoribbons 扶手椅石墨烯纳米带自旋塞贝克效应的机电控制

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-22 DOI: 10.1016/j.jmmm.2025.172966

Rouhollah Farghadan, Elham Azadi

引用次数: 0

Investigation of Ba2SmOsO6 and Ba2InOsO6 double perovskite oxide for spintronic and linear optoelectronic applications using DFT and DFT+U methods 用DFT和DFT+U方法研究Ba2SmOsO6和Ba2InOsO6双钙钛矿氧化物在自旋电子和线性光电应用中的应用

IF 2.5 3区材料科学

Journal of Magnetism and Magnetic Materials Pub Date : 2025-03-22 DOI: 10.1016/j.jmmm.2025.172980

E. Darkaoui , S. Mouslih , J. Islah , M. Archi , A. Abbassi , S. Taj , B. Manaut , H. Ez-Zahraouy

{"title":"Investigation of Ba2SmOsO6 and Ba2InOsO6 double perovskite oxide for spintronic and linear optoelectronic applications using DFT and DFT+U methods","authors":"E. Darkaoui , S. Mouslih , J. Islah , M. Archi , A. Abbassi , S. Taj , B. Manaut , H. Ez-Zahraouy","doi":"10.1016/j.jmmm.2025.172980","DOIUrl":"10.1016/j.jmmm.2025.172980","url":null,"abstract":"<div><div>Spintronics is an emerging field that uses electronic spins for a variety of technical motivations. In this work, we used density functional theory (DFT) to investigate the ferromagnetic properties of <span><math><mrow><mi>B</mi><msub><mrow><mi>a</mi></mrow><mrow><mn>2</mn></mrow></msub><mi>M</mi><mi>O</mi><mi>s</mi><msub><mrow><mi>O</mi></mrow><mrow><mn>6</mn></mrow></msub></mrow></math></span> double-perovskite materials. We determined that the ferromagnetic indicate had the lowest level of energy in our recherche for the most ground-like configuration. We conducted stability tests and found that <span><math><mrow><mi>B</mi><msub><mrow><mi>a</mi></mrow><mrow><mn>2</mn></mrow></msub><mi>M</mi><mi>O</mi><mi>s</mi><msub><mrow><mi>O</mi></mrow><mrow><mn>6</mn></mrow></msub></mrow></math></span> exhibits thermodynamiclly, dynamically, and mechanically stability. They demonstrated the half-metallic ferromagnetic character of <span><math><mrow><mi>B</mi><msub><mrow><mi>a</mi></mrow><mrow><mn>2</mn></mrow></msub><mi>S</mi><mi>m</mi><mi>O</mi><mi>s</mi><msub><mrow><mi>O</mi></mrow><mrow><mn>6</mn></mrow></msub></mrow></math></span> through their band structure and density of states. These double-perovskites show potential for use in spintronic applications, as evidenced by their good magnetic moment values and spin polarisation factor. According to the studies, both materials have the ability to transmit at low energy, which makes them viable options for optoelectronic uses. Additionally, the discovery of discrete peaks for reflectivity and absorption signifies potential uses in flexible optical systems and sensors. Novel photonic material development is made possible by the refractive index’s dispersion properties.</div></div>","PeriodicalId":366,"journal":{"name":"Journal of Magnetism and Magnetic Materials","volume":"622 ","pages":"Article 172980"},"PeriodicalIF":2.5,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0