Journal Home Online First Current Issue Archive For Authors Journal Information 中文版

Engineering >> 2020, Volume 6, Issue 2 doi: 10.1016/j.eng.2018.11.034

Perspective and Prospects for Rare Earth Permanent Magnets

a School of Physics & Centre for Research on Adaptive Nanostructures and Nanodevices, Trinity College Dublin, Dublin 2, Ireland

b Department of Materials Science, Beihang University, Beijing 100191, China

Received: 2018-08-07 Revised: 2018-09-19 Accepted: 2018-11-12 Available online: 2019-06-19

Next Previous

Abstract

Rare earth permanent magnets constitute a mature technology, but the shock of the 2011 rare earth crisis led to the re-evaluation of many ideas from the 1980s and 1990s about possible new hard magnets containing little or no rare earth (or heavy rare earth). Nd–Fe–B magnets have been painstakingly and skillfully optimized for a wide range of applications in which high performance is required at reasonable cost. Sm–Co is the material of choice when high-temperature stability is required, and Sm–Fe–N magnets are making their way into some niche applications. The scope for improvement in these basic materials by substitution has been rather thoroughly explored, and the effects of processing techniques on the microstructure and hysteresis are largely understood. A big idea from a generation ago—which held real potential to raise the record energy product significantly—was the oriented exchange-spring hard/soft nanocomposite magnet; however, it has proved very difficult to realize. Nevertheless, the field has evolved, and innovation has flourished in other areas. For example, electrical personal transport has progressed from millions of electric bicycles to the point where cars and trucks with electrical drives are becoming mainstream, and looks ready to bring the dominance of the internal combustion engine to an end. As the limitations of particular permanent magnets become clearer, ingenuity and imagination are being used to design around them, and to exploit the available mix of rare earth resources most efficiently. Huge new markets in robotics beckon, and the opportunities offered by additive manufacturing are just beginning to be explored. New methods of increasing magnet stability at elevated temperature are being developed, and integrated multifunctionality of hard magnets with other useful properties is now envisaged. These themes are elaborated here, with various examples.

Figures

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9

Fig. 10

Fig. 11

References

[ 1 ] Coey JMD. Permanent magnets. In: Webster JG, editor. Wiley encyclopedia of electrical and electronic engineering. Hoboken: John Wiley & Sons, Inc.; 2014. link1

[ 2 ] Skomski R, Coey JMD. Magnetic anisotropy—how much is enough for a permanent magnet? Scr Mater 2016;112:3–8. link1

[ 3 ] Skomski R. Permanent magnets: history, current research, and outlook. In: Zhukov A, editor. Novel functional magnetic materials. Cham: Springer International Publishing AG; 2016. p. 359–95. link1

[ 4 ] Hono K, Sepehri-Amin H. Prospect for HRE-free high coercivity Nd–Fe–B permanent magnets. Scr Mater 2018;151:6–13. 154:277–283. link1

[ 5 ] Hu B, Rao X, Wang Y. Rare earth permanent magnet materials. 2 volumes. Beijing: Metallurgical Industry Press; 2017. Chinese. link1

[ 6 ] Coey JMD. Magnetism and magnetic materials. Cambridge: Cambridge University Press; 2010. link1

[ 7 ] Brown WF. Micromagnetics. New York: Interscience Publishers, Inc.; 1963. link1

[ 8 ] Coey JMD. Hard magnetic materials: a perspective. IEEE Trans Magn 2011;47 (12):4671–81. link1

[ 9 ] Skokov KP, Gutfleisch O. Heavy rare earth free, free rare earth and rare earth free magnets—vision and reality. Scr Mater 2018;154:289–94. link1

[10] Mohapatra J, Liu JP. Rare-earth-Efree permanent magnets: the past and future. In: Bruck E, editor. Handbook of Magnetic Mterials, 27. Amsterdam: Elsevier; 2018. p. 1–58. link1

[11] Jellinghaus W. New alloys with high coercive force. Z Tech Physik 1936;17:33–6. link1

[12] Klemmer T, Hoydick D, Okumura H, Zhang B, Soffa WA. Magnetic hardening and coercivity mechanisms in L10 ordered FePd ferromagnets. Scr Metall Mater 1995;33(10–11):1793–805. link1

[13] Kooy C, Enz U. Experimental and theoretical study of the domain configuration in thin layers of BaFe12O19. Philips Res Repts 1960;15:7–29. link1

[14] Sagawa M, Fujimura S, Yamamoto H, Matsuura Y, Hiraga K. Permanent magnet materials based on the rare earth–iron–boron tetragonal compounds. IEEE Trans Magn 1984;20(5):1584–9. link1

[15] Sagawa M, Hirosawa S, Yamamoto H, Fujimura S, Matsuura Y. Nd–Fe–B permanent magnet materials. Jpn J Appl Phys 1987;26(6):785–800. link1

[16] Herbst JF. R2Fe14B materials: intrinsic properties and technological aspects. Rev Mod Phys 1991;63(4):819–98. link1

[17] Kumar K. RETM5 and RE2TM17 permanent magnets development. J Appl Phys 1988;63(6):R13–57. link1

[18] Coey JMD, Sun H. Improved magnetic properties by treatment of iron-based rare earth intermetallic compounds in ammonia. J Magn Magn Mater 1990;87 (3):L251–4. link1

[19] Iriyama T, Kobayashi K, Imaoka N, Fukuda T, Kato H, Nakagawa Y. Effect of nitrogen content on magnetic properties of Sm2Fe17Nx (0 < x < 6). IEEE Trans Magn 1992;28(5):2326–31. link1

[20] Kalache A, Markou A, Selle S, Höche T, Sahoo R, Fecher GH, et al. Heteroepitaxial growth of tetragonal Mn2.7–xFexGa1.3 (0  x  1.2) Heusler films with perpendicular magnetic anisotropy. APL Mater 2017;5(9):096102. link1

[21] Skomski R, Coey JMD. Giant energy product in nanostructured two-phase magnets. Phys Rev B Condens Matter 1993;48(21):15812–6. link1

[22] Kneller EF, Hawig R. The exchange-spring magnet: a new material principle for permanent magnets. IEEE Trans Magn 1991;27(4):3588–660. link1

[23] Jiang JS, Bader SD. Rational design of the exchange-spring permanent magnet. J Phys Condens Matter 2014;26(6):064214. link1

[24] Coey JMD, O’Donnell K, Qinian Q, Touchais E, Jack KH. The magnetization of a00Fe16N2. J Phys Condens Matter 1994;6(4):L23–8. link1

[25] Dobosz I, Gumowska W, Czapkiewicz M. Structure and magnetic properties of Co nanowires electrodeposited into the pores of anodic alumina membranes. J Solid State Electrochem 2014;18(11):2963–72. link1

[26] Dumestre F, Chaudret B, Amiens C, Fromen MC, Casanove MJ, Renaud P, et al. Shape control of thermodynamically stable cobalt nanorods through organometallic chemistry. Angew Chem Int Ed Engl 2002;41(22):4286–9. link1

[27] Harris VG, Chen Y, Yang A, Yoon S, Chen Z, Geiler AL, et al. High coercivity cobalt carbide nanoparticles processed via polyol reaction: a new permanent magnet material. J Phys D Appl Phys 2010;43(16):165003. link1

[28] Li X, Lou L, Song W, Huang G, Hou F, Zhang Q, et al. Novel bimorphological anisotropic bulk nanocomposite materials with high energy products. Adv Mater 2017;29(16):1606430. link1

[29] Gandha K, Elkins K, Poudyal N, Liu X, Liu JP. High energy product developed from cobalt nanowires. Sci Rep 2014;4(1):5345. link1

[30] Anagnostopoulou E, Grindi B, Lacroix LM, Ott F, Panagiotopoulos I, Viau G. Dense arrays of cobalt nanorods as rare-earth free permanent magnets. Nanoscale 2016;8(7):4020–9. link1

[31] Ener S, Anagnostopoulou E, Dirba I, Lacroix LM, Ott F, Blon T, et al. Consolidation of cobalt nanorods: a new route for rare-earth free nanostructured permanent magnets. Acta Mater 2018;145:290–7. link1

[32] Gandha K, Mohapatra J, Liu JP. Coherent magnetization reversal and high magnetic coercivity in Co nanowire assemblies. J Magn Magn Mater 2017;438:41–5. link1

[33] Katter M, Wecker J, Schultz L, Grössinger R. Magnetocrystalline anisotropy of Sm2Fe17N2. J Magn Magn Mater 1990;92(1):L14–8. link1

[34] Skomski R. Interstitial modification. In: Coey JMD, editor. Rare-earth iron permanent magnets. Oxford: Clarendon Press; 1996. p. 178–217. link1

[35] Miraglia S, Soubeyroux JL, Kolbeck C, Isnard O, Fruchart D, Guillot M. Structural and magnetic properties of ternary nitrides R2Fe17Nx (R  Nd, Sm). J Less Common Met 1991;171(1):51–61. link1

[36] Chiba A, Hokamoto K, Sugimoto S, Kozuka T, Mori A, Kakimoto E. Explosive consolidation of Sm–Fe–N and Sm–Fe–N/(Ni, Co) magnetic powders. J Magn Magn Mater 2007;310(2):e881–3. link1

[37] Hu BP, Rao XL, Xu JM, Liu GC, Wang YZ, Dong XL, et al. Magnetic properties of sintered Sm2Fe17Ny magnets. J Appl Phys 1993;74(1):489–94. link1

[38] Chiba A, Ooyabu K, Morizono Y, Maeda T, Sugimoto S, Kozuka T, et al. Shock consolidation of Sm–Fe–N magnetic powders and magnetic properties. Mater Sci Forum 2004;449–452:1037–40. link1

[39] Zhang DT, Yue M, Zhang JX. Study on bulk Sm2Fe17Nx sintered magnets prepared by spark plasma sintering. Powder Metall 2007;50(3):215–8. link1

[40] Saito T. Consolidation of Sm5Fe17 powder by spark plasma sintering method. Mater Sci Eng B 2008;150(1):38–42. link1

[41] Saito T. Magnetic properties of Sm–Fe–N anisotropic magnets produced by magnetic-field-assisted spark plasma sintering. Mater Sci Eng B 2010;167 (2):75–9. link1

[42] Saito T, Deguchi T, Yamamoto H. Magnetic properties of Sm–Fe–N bulk magnets produced from Cu-plated Sm–Fe–N powder. AIP Adv 2017;7 (5):056204. link1

[43] Otani Y, Moukarika A, Sun H, Coey JMD, Devlin E, Harris IR. Metal bonded Sm2Fe17N3–d magnets. J Appl Phys 1991;69(9):6735–7. link1

[44] Matsuura M, Shiraiwa T, Tezuka N, Sugimoto S, Shoji T, Sakuma N, et al. High coercive Zn-bonded Sm–Fe–N magnets prepared using fine Zn particles with low oxygen content. J Magn Magn Mater 2018;452:243–8. link1

[45] Noguchi K, Machida K, Yamamoto K, Nishimura M, Adachi G. Highperformance resin-bonded magnets produced from zinc metal-coated Sm2(Fe0.9Co0.1)17Nx fine powders. Appl Phys Lett 1999;75(11):1601–3. link1

[46] Otogawa K, Takagi K, Asahi T. Consolidation of Sm2Fe17N3 magnets with Smbased eutectic alloy binder. J Alloys Compd 2018;746:19–26. link1

[47] Kobayashi K, Skomski R, Coey JMD. Dependence of coercivity on particle size in Sm2Fe17N3 powders. J Alloys Compd 1995;222(1–2):1–7. link1

[48] Ishikawa T, Yokosawa K, Watanabe K, Ohmori K. Modified process for highperformance anisotropic Sm2Fe17N3 magnet powder. J Phys Conf Ser 2011;266 (1):012033. link1

[49] Katter M, Wecker J, Schultz L. Structural and hard magnetic properties of rapidly solidified Sm–Fe–N. J Appl Phys 1991;70(6):3188–96. link1

[50] Coey JMD, Stamenov P, Porter SB, Venkatesan M, Zhang R, Iriyama T. Sm–Fe–N revisited; remanence enhancement in melt-spun Nitroquench material. J Magn Magn Mater 2019;480:186–92. link1

[51] Brown WF. Virtues and weaknesses of the domain concept. Rev Mod Phys 1945;17(1):15–9. link1

[52] Hono K. Rare earth permanent magnets with ultimate hard magnetic properties [abstract]. In: Proceedings of 2018 IEEE International Magnetics Conference (INTERMAG); 2018 Apr 23–27; Singapore. Piscataway: IEEE; 2018. p. 829. link1

[53] Gabay AM, Hadjipanayis GC. Recent developments in RFe12-type compounds for permanent magnets. Scr Mater 2018;154:284–8. link1

[54] Hirosawa S, Nishino M, Miyashita S. Perspectives for high performance permanent magnets: applications, coercivity, and new materials. Adv Nat Sci Nanosci Nanotechnol 2017;8(1):013002. link1

[55] Kuno T, Suzuki S, Urushibata K, Kobayashi K, Sakuma N, Yano M, et al. (Sm,Zr) (Fe,Co)11.0-11.5Ti1.0-0.5 compounds as new permanent magnet materials. AIP Adv 2016;6(2):025221. link1

[56] Coey JMD, Otani Y, Sun H, Hurley DPF. Magnetic properties of interstitial compounds Sm(Fe11Ti)X1–d (X = N, C). J Magn Soc Jpn 1991;15(4):769–72. link1

[57] Yang YC, Zhang X, Ge S, Pan Q, Kong L, Li H, et al. Magnetic and crystallographic properties of novel Fe-rich rare-earth nitrides of the type RTiFe11N1–d. J Appl Phys 1991;70(10):6001–5. link1

[58] Hirayama Y, Takahashi YK, Hirosawa S, Hono K. NdFe12Nx hard-magnetic compound with high magnetization and anisotropy field. Scr Mater 2015;95:70–2. link1

[59] Sato T, Ohsuna T, Yano M, Kato A, Kaneko Y. Permanent magnetic properties of NdFe12Nx sputtered films epitaxially grown on V buffer layer. J Appl Phys 2017;122(5):053903. link1

[60] Hirayama Y, Takahashi YK, Hirosawa S, Hono K. Intrinsic hard magnetic properties of Sm(Fe1–xCox)12 compound with the ThMn12 structure. Scr Mater 2017;138:62–5. link1

[61] Tozman P, Sepehri-Amin H, Takahashi YK, Hirosawa S. Hono K. Intrinsic magnetic properties of Sm(Fe1–xCox)11Ti and Zr-substituted Sm1–yZry(Fe0.8Co0.2)11.5Ti0.5 compounds with ThMn12 structure toward the development of permanent magnets. Acta Mater 2018;153:354–63. link1

[62] Suzuki S, Kuno T, Urushibata K, Kobayashi K, Sakuma N, Washio K, et al. A (Nd, Zr)(Fe,Co)11.5Ti0.5Nx compound as a permanent magnet material. AIP Adv 2014;4(11):117131. link1

[63] Körner W, Krugel G. Elsässer C Theoretical screening of intermetallic ThMn12- type phases for new hard-magnetic compounds with low rare earth content. Sci Rep 2016;6:24686. link1

[64] Körner W, Krugel G, Urban DF, Elsässer C. Screening of rare-earth-lean intermetallic 1-11 and 1-11-X compounds of YNi9In2-type for hard-magnetic applications. Scr Mater 2018;154:295–9. link1

[65] Goll D, Loeffler R, Hohs D, Schneider G. Reaction sintering as a highthroughput approach for magnetic materials development. Acta Met 2018;146:355–61. link1

[66] Loewe K, Benke D, Kübel C, Lienig T, Skokov KP, Gutfleisch O. Grain boundary diffusion of different rare earth elements in Nd–Fe–B sintered magnets by experiment and FEM simulation. Acta Mater 2017;124:421–9. link1

[67] Hussain M, Zhao LZ, Zhang C, Jiao DL, Zhong XC, Liu ZW. Compositiondependent magnetic properties of melt-spun La or/and Ce substituted nanocomposite NdFeB alloys. Phys B 2016;483:69–74. link1

[68] Rao X, Niu E, Du F, Hu B. Effect of cerium on magnetic properties of sintered R– Fe–B permanent magnet. [abstract]. Proceedings of 2018 IEEE International Magnetics Conference (INTERMAG); 2018 Apr 23–27; Singapore, Singapore. Piscataway: IEEE; 2018. link1

[69] Kuzmin MD, Skokov KP, Jian H, Radulov I, Gutfleisch O. Towards highperformance permanent magnets without rare earths. J Phys Condens Matter 2014;26(6):064205. link1

[70] Coey JMD. Permanent magnets: plugging the gap. Scr Mater 2012;67 (6):524–9. link1

[71] Paranthaman MP, Shafer CS, Elliott AM, Siddel DH, McGuire MA, Springfield RM, et al. Binder jetting: a novel NdFeB bonded magnet fabrication process. JOM 2016;68(7):1978–82. link1

[72] Huber C, Abert C, Bruckner F, Groenefeld M, Muthsam O, Schuschnigg S, et al. 3D print of polymer bonded rare-earth magnets, and 3D magnetic field scanning with an end-user 3D printer. Appl Phys Lett 2016;109(16):162401. link1

[73] Li L, Tirado A, Nlebedim IC, Rios O, Post B, Vlastimil K, et al. Big area additive manufacturing of high performance bonded NdFeB magnets. Sci Rep 2016;6:36212. link1

[74] Compton BG, Kemp JW, Novikov TV, Pack RC, Nlebedim CI, Duty CE, et al. Direct-write 3D printing of NdFeB bonded magnets. Mater Manuf Process 2018;33(1):109–13. link1

[75] Li L, Tirado A, Conner BS, Chi MF, Elliott AM, Rios O, et al. A novel method combining additive manufacturing and alloy infiltration for NdFeB bonded magnet fabrication. J Magn Magn Mater 2017;438:163–7. link1

[76] Huber C, Abert C, Bruckner F, Groenefeld M, Schuschnigg S, Teliban I, et al. 3D printing of polymer-bonded rare-earth magnets with a variable magnetic compound fraction for a predefined stray field. Sci Rep 2017;7(1):9419. link1

[77] Kolb B, Huber F, Akbulut B, Donocik C, Urban N, Maurer D, et al. Laser beam melting of NdFeB for the production of rare-earth magnets. In: Proceedings of the 6th International Electric Drives Production Conference; 2016 Nov 30–Dec 1; Nuremberg, Germany. Piscataway: IEEE; 2016. p. 34–40. link1

[78] Jac´imovic´ J, Binda F, Herrmann LG, Greuter F, Genta J, Calvo M, et al. Net shape 3D printed NdFeB permanent magnet. Adv Elec Mater 2017;19(8):1700098. link1

[79] Baldissera AB, Pavez P, Wendhausen PAP, Ahrens CH. Mascheroni JM. Additive manufacturing of bonded Nd–Fe–B—effect of process parameters on magnetic properties. IEEE Trans Magn 2017;53(11):7948722. link1

[80] Li L, Jones K, Sales B, Pries JL, Nlebedim IC, Jin K, et al. Fabrication of highly dense isotropic Nd–Fe–B nylon bonded magnets via extrusion-based additive manufacturing. Addit Manuf 2018;21:495–500. link1

[81] Shen A, Bailey CP, Ma AWK, Dardona S. UV-assisted direct write of polymerbonded magnets. J Magn Magn Mater 2018;462:220–5. link1

[82] Li L, Post B, Kunc V, Elliott AM, Paranthaman MP. Additive manufacturing of near-net-shape bonded magnets: prospects and challenges. Scr Mater 2017;135:100–4. link1

[83] Popov V, Koptyug A, Radulov I, Maccari F, Muller G. Prospects of additive manufacturing of rare-earth and non-rare-earth permanent magnets. Proc Manuf 2018;21:100–8. link1

[84] Khazdozian HA, Manzano JS, Gandha K, Slowing II, Nlebedim IC. Recycled Sm–Co bonded magnet filaments for 3D printing ofmagnets. AIP Adv 2018;8(5):056722. link1

[85] Palmero EM, Rial J, de Vicente J, Camarero J, Skårman B, Vidarsson H, et al. Development of permanent magnet MnAlC/polymer composites and flexible filament for bonding and 3D-printing technologies. Sci Technol Adv Mater 2018;19(1):465–73. link1

[86] White EMH, Kassen AG, Simsek E, Tang W, Ott RT, Anderson IE. Net shape processing of alnico magnets by additive manufacturing. IEEE Trans Magn 2017;53(11):1–6. link1

[87] Cullity BD, Graham CD. Introduction to magnetic materials. Piscataway: Wiley-IEEE Press; 2008. link1

[88] Xia W, He Y, Huang H, Wang H, Shi X, Zhang T, et al. Initial irreversible losses and enhanced high-temperature performance of rare-earth permanent magnets. Adv Funct Mater 2019;24:19000690. link1

Related Research