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金属学报  2018, Vol. 54 Issue (3): 457-462    DOI: 10.11900/0412.1961.2017.00211
  本期目录 | 过刊浏览 |
各向异性稀土永磁薄膜的磁黏滞性
孙亚超, 朱明刚(), 韩瑞, 石晓宁, 俞能君, 宋利伟, 李卫
钢铁研究总院功能材料研究所 北京 100081
Magnetic Viscosity of Anisotropic Rare Earth Permanent Films
Yachao SUN, Minggang ZHU(), Rui HAN, Xiaoning SHI, Nengjun YU, Liwei SONG, Wei LI
Division of Functional Material, Central Iron & Steel Research Institute, Beijing 100081, China;
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摘要: 

利用直流磁控溅射技术在Si基底上制备了NdFeB、CeFeB和NdFeB/CeFeB薄膜。XRD和磁滞回线结果表明,所制备的薄膜样品均具有良好的c轴取向,其中NdFeB单层薄膜垂直于薄膜表面方向的室温矫顽力Hc达到1377.4 kA/m。研究了3种不同薄膜样品的磁黏滞系数S随温度(5~300 K) 的变化趋势,发现在低温(5 K)条件下,3种薄膜的S值非常接近,且都小于1,这是由于低温时薄膜晶格内的热起伏已经不足以使畴壁跃过位垒达到能量更小的位置。通过研究温度和外场对3种薄膜磁黏滞性的影响,发现NdFeB/CeFeB薄膜的磁黏滞系数更接近于CeFeB单层薄膜,且远小于NdFeB薄膜,说明通过双硬磁复合能够有效降低薄膜磁化强度对时间的依赖性,提高其时间稳定性。

关键词 永磁薄膜磁性能磁黏滞    
Abstract

Rare earth permanent thin films are useful for magnetic microdevices such as micromotors, since its excellent magnetic properties are able to raise the performance of the devices. In order to judge the reliability of permanent magnet materials, it is quite theoretical and practical to study the time dependence behavior of magnetization, that is, magnetic viscosity or magnetic after-effect. In this work, NdFeB, CeFeB and NdFeB/CeFeB films were fabricated on the Si substrates by direct current (DC) magnetron sputtering. A Ta underlayer of 50 nm and a coverlayer of 40 nm were sputtered at room temperature to align the easy axis of the RE2Fe14B grains perpendicular to the film plane and to prevent oxidation of the magnetic films, respectively. NdFeB and CeFeB magnetic films were deposited at 903 and 883 K, respectively, and submitted to an in-situ rapid thermal annealing at 948 K for 30 min. The microstructure and magnetic properties of the films were characterized by XRD and physical property measurement system (PPMS). The results indicate that the films show excellent perpendicular anisotropy. A coercivity Hc of 1377.4 kA/m is obtained for NdFeB monolayer film at room temperature. The magnetic viscosity coefficient (S) of the films was studied over a range of temperatures (5~300 K). It is found that the values of S for all films are less than 1, and are quite similar at low temperature (5 K). Both weakened thermal agitation and strengthened anisotropy energy barriers are supposed to decrease transition frequency (f) and prolong relaxation time (τ) at low temperature, which lead to S decreasing. The magnetic viscosity of NdFeB/CeFeB thin film is as similar as that of the CeFeB monolayer thin film, and both are much smaller than that of the NdFeB film. It is shown that the dual-hard magnetic layer structure can effectively reduce the viscosity coefficient and improve the time stability of the NdFeB/CeFeB thin film. Furthermore, the temperature dependence of the initial decay rates (dM/dt) from 0 s to 10 s was discussed. The initial magnetic decay of the film demonstrates a similar temperature behavior as the magnetic viscosity coefficient S.

Key wordspermanent thin film    magnetic property    magnetic viscosity
收稿日期: 2017-06-02     
基金资助:资助项目 国家重点基础研究发展计划项目No.2014CB643701和国家自然科学基金面上项目No.51571064
作者简介:

作者简介 孙亚超,男,1988年生,博士

引用本文:

孙亚超, 朱明刚, 韩瑞, 石晓宁, 俞能君, 宋利伟, 李卫. 各向异性稀土永磁薄膜的磁黏滞性[J]. 金属学报, 2018, 54(3): 457-462.
Yachao SUN, Minggang ZHU, Rui HAN, Xiaoning SHI, Nengjun YU, Liwei SONG, Wei LI. Magnetic Viscosity of Anisotropic Rare Earth Permanent Films. Acta Metall Sin, 2018, 54(3): 457-462.

链接本文:

https://www.ams.org.cn/CN/10.11900/0412.1961.2017.00211      或      https://www.ams.org.cn/CN/Y2018/V54/I3/457

图1  室温下样品垂直(⊥)和平行(//)于膜面方向的磁滞回线
图2  NdFeB、CeFeB和NdFB/CeFeB薄膜的XRD谱
图3  NdFeB、CeFeB和NdFeB/CeFeB薄膜矫顽力Hc随温度变化曲线
图4  NdFeB/CeFeB薄膜的磁化强度M/M0在外场H0 (H0=Hc)作用下随时间t和时间对数ln(t+t0)的变化曲线
图5  磁性薄膜的磁粘滞系数S随温度变化关系
图6  磁性薄膜起始时间段(0~10 s)磁化强度变化率dM/dt随温度的变化关系
图7  室温下NdFeB、CeFeB和NdFeB/CeFeB薄膜的S随外场的变化关系
[1] Rodewald W, Wall B, Katter M, et al.Top Nd-Fe-B magnets with greater than 56 MGOe energy density and 9.8 kOe coercivity[J]. IEEE Trans. Magn., 2002, 38: 2955
[2] Sagawa M, Fujimura S, Togawa N, et al.New material for permanent magnets on a base of Nd and Fe (invited)[J]. J. Appl. Phys., 1984, 55: 2083
[3] Gutfleisch O G, Willard M A, Brück E, et al.Magnetic materials and devices for the 21st century: Stronger, lighter, and more energy efficient[J]. Adv. Mater., 2011, 23: 821
[4] Davies B E, Mottram R S, Harris I R.Recent developments in the sintering of NdFeB[J]. Mater. Chem. Phys., 2001, 67: 272
[5] Huang S L, Feng H B, Zhu M G, et al.Optimal design of sintered Ce9Nd21FebalB1 magnets with a low-melting-point (Ce, Nd)-rich phase[J]. Int. J. Miner. Metall. Mater., 2015, 22: 417
[6] Feng W C, Gao R W, Li W.Effects of grain-size distribution on effective anisotropy and coercivity for nanocrystalline hard magnetic material[J]. Acta Metall. Sin., 2005, 41: 347(冯维存, 高汝伟, 李卫. 晶粒尺寸分布对纳米硬磁材料有效各向异性和矫顽力的影响 [J]. 金属学报, 2005, 41: 347)
[7] Preisach F.über die magnetische Nachwirkung[J]. Z. Phys., 1935, 94: 277
[8] Street R, Woolley J C.A study of magnetic viscosity[J]. Proc. Phys. Soc., 1949, 62A: 562
[9] Jin H M.Magnetic Physics [M]. Beijing: Science Press, 2013: 277(金汉民. 磁性物理 [M]. 北京: 科学出版社, 2013: 277)
[10] Zhu M G, Li W, Wang J D, et al.Influence of Ce content on the rectangularity of demagnetization curves and magnetic properties of Re-Fe-B magnets sintered by double main phase alloy method[J]. IEEE Trans. Magn., 2014, 50: 1000104
[11] Herbst J F, Meyer M S, Pinkerton F E. Magnetic hardening of Ce2Fe14B [J]. J. Appl. Phys., 2012, 111: 07A718
[12] Alam A, khan M, McCallum R W, et al. Site-preference and valency for rare-earth sites in (R-Ce)2Fe14B magnets[J]. Appl. Phys. Lett. 2013, 102: 042402
[13] Skoug E J, Meyer M S, Pinkerton F E, et al.Crystal structure and magnetic properties of Ce2Fe14-xCoxB alloys[J]. J. Alloys Compd., 2013, 574: 552
[14] Li Z B, Shen B G, Zhang M, et al.Substitution of Ce for Nd in preparing R2Fe14B nanocrystalline magnets[J]. J. Alloys Compd., 2015, 628: 325
[15] Villas-Boas V, González J M, Cebollada F, et al.Magnetic viscosity and coercivity analysis in mechanically alloyed and melt-spun NdDyFeB magnets[J]. J. Magn. Magn. Mater., 1998, 185: 180
[16] Villas-Boas V, Missell F P, Schneider G, et al.Coercivity and magnetic viscosity in Nd80Fe15B5[J]. Solid State Commun., 1990, 74: 683
[17] Martinez J C G, Missell F P, Landgraf F J G. Magnetic viscosity and texture in sintered NdFeB and NdDyFeB magnets[J]. J. Magn. Magn. Mater., 1988, 73: 267
[18] Collocott S J, Dunlop J B.The fluctuation field and anomalous magnetic viscosity in commercial NdFeB alloys, AlNiCo and the bulk amorphous ferromagnets Nd60Fe30Al10 and Nd60Fe20Co10Al10[J]. J. Magn. Magn. Mater., 2008, 320: 2089
[19] Jahn L, Schumann R, Rodewald W.Magnetic viscosity of modified neodymium iron boron magnets with high coercivities[J]. J. Magn. Magn. Mater., 1996, 153: 302
[20] Zhang H W, Zhang W Y, Yan A R, et al.Magnetization reversal behavior and magnetic viscosity of nanocomposite Nd3.6Pr5.4Fe83Co3B5 prepared by melt spinning[J]. Acta Phys. Sin., 1999, 48(suppl.): S211(张宏伟, 张文勇, 阎阿儒等. 快淬Nd3.6Pr5.4Fe83Co3B5薄带的反磁化行为和磁黏滞性 [J]. 物理学报, 1999, 48(增刊): S211)
[21] Li W D, Tan X H, Ren K Z, et al.Magnetic viscosity behavior and exchange interaction for Nd2Fe14B/α-Fe nanocomposite permanent alloys[J]. Acta Metall. Sin., 2016, 52: 561(李维丹, 谭晓华, 任科智等. Nd2Fe14B/α-Fe系纳米晶复合永磁合金的磁黏滞行为及其交互作用 [J]. 金属学报, 2016, 52: 561)
[22] Givord D, Lienard A, Tenaud P, et al.Magnetic viscosity in Nd-Fe-B sintered magnets[J]. J. Magn. Magn. Mater., 1987, 67: L281
[23] Néel L.Théorie du tra?nage magnétique des ferromagnétiques en grains fins avec application aux terres cuites[J]. Ann. Geophys., 1949, 5: 99
[24] Phillips J H, Street R, Woolley J C.LIX. Magnetic viscosity in precipitation alloys: FeNiAl, Fe2NiAl and Alnico[J]. Philos. Mag., 1954, 45: 505
[25] Phillips J H, Woolley J C, Street R.The influence of temperature on magnetic viscosity[J]. Proc. Phys. Soc., 1955, 68B: 345
[26] Néel L.Bases d’une nouvelle théorie générale du champ coercitif[J]. Ann. Univ. Grenoble, 1946, 22: 299
[27] Yang N, Dennis K W, McCallum R W, et al. Role of the Fe sublattice on the Invar anomaly in R2Fe14B compounds[J]. J. Appl. Phys., 2003, 93: 7990
[28] Ma Q F, Fang R S, Xiang L C, et al.Handbook of Practical Thermophysical Properties [M]. Beijing: China Agricultural Machinery Press, 1986: 78)(马庆芳, 方荣生, 项立成等. 实用热物理性质手册[M]. 北京: 中国农业机械出版社, 1986: 78)
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