Permanent Magnets

A special issue of Magnetochemistry (ISSN 2312-7481).

Deadline for manuscript submissions: closed (31 December 2019) | Viewed by 12745

Special Issue Editor


E-Mail Website
Guest Editor
Ames Laboratory, US DOE, Iowa State University, 233 Spedding Hall, Ames, IA 50011, USA
Interests: magnetism and transport phenomena of lanthanide based compounds; quantum materials; nano-magnetism; caloric materials; permanent magnet; superconductivity; 2D materials

Special Issue Information

Dear Colleagues,

Permanent magnets are one of the most critical components in many devices, including electric motors, household appliances, wind turbines, and hybrid vehicles. Rapidly-increasing demand of high-performance permanent magnets make strong scientific cases for developing competing permanent magnets that do not rely on elements having high criticality and that are expensive. Thus, many scientists and engineers from all over the world are working on this topic to find better properties for various permanent magnet materials, including rare earth based, ferrite, alnico, and iron-nitrate. In this Special Issue we would like to invite scientists who are working in this field to contribute their original research and review articles that cover theoretical and modeling studies, synthesis, characterization and optimization of both rare earth and non-rare earth-based permanent magnet materials.

Potential topics include, but are not limited to:

  • Theoretical and modeling study
  • Fundamental study of hard magnetic materials
  • Synthesis, characterization and optimization
  • Restructuring and microstructural study
  • Research on recycling of permanent magnet materials

Dr. Arjun K. Pathak
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Magnetochemistry is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Maximum energy product
  • Coercivity
  • Magnetocrystalline anisotropy
  • Alnico
  • Rare earth
  • Permanent magnet
  • Sintered magnet
  • Bonded magnet
  • Melt spun ribbons
  • Ferrite magnet

Published Papers (4 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

12 pages, 1976 KiB  
Article
Effect of Ga and Zr Substitution on the Properties of Dy2Fe17−XZrX and Dy2Fe16Ga1−xZrx (0 ≤ x ≤ 1) Intermetallic Compounds Prepared via Arc Melting Process
by Jiba Nath Dahal, K.S. Syed Ali, S.R. Mishra and Dipesh Neupane
Magnetochemistry 2020, 6(1), 9; https://doi.org/10.3390/magnetochemistry6010009 - 21 Feb 2020
Cited by 4 | Viewed by 2319
Abstract
The effects of substitution of Zr and Ga on the structural and magnetic properties of Dy2Fe17 intermetallic compound were investigated in this study. The Rietveld analysis confirmed that the crystalline system was a Th2Ni17 structure. Lattice parameters [...] Read more.
The effects of substitution of Zr and Ga on the structural and magnetic properties of Dy2Fe17 intermetallic compound were investigated in this study. The Rietveld analysis confirmed that the crystalline system was a Th2Ni17 structure. Lattice parameters a (Å) and c (Å), unit cell volume (Å3), and bonding distance (Å) were calculated using Rietveld analysis. The unit cell volume of Dy2Fe17−xZrx and Dy2Fe16Ga1−xZrx increased linearly with Zr and Ga substitution. The Curie temperature (Tc) of Dy2Fe17−xZrx and Dy2Fe16Ga1−xZrx was found to be Zr content-dependent. The maximum Curie temperatures were observed at 510 K (x = 0.75 Zr content) for Dy2Fe17−xZrx and 505.1 K (x = 0.5 Zr content) for Dy2Fe16Ga1−xZrx, which are 102 K and 97 K higher than the value found for Dy2Fe17, respectively. The room-temperature Mössbauer analysis showed a decrease in the average hyperfine field and increases in the isomer shift with Zr doping. The overall improvement in Curie temperature with the substitution strategy of Zr–Ga substitution in 2:17 intermetallic compounds could find potential use of these magnetic compounds in high-temperature applications. Full article
(This article belongs to the Special Issue Permanent Magnets)
Show Figures

Figure 1

10 pages, 2838 KiB  
Article
Effects of High Magnetic Fields on Phase Transformations in Amorphous Nd2Fe14B
by Michael S. Kesler, Brandt A. Jensen, Lin Zhou, Olena Palasyuk, Tae-Hoon Kim, Matthew J. Kramer, Ikenna C. Nlebedim, Orlando Rios and Michael A. McGuire
Magnetochemistry 2019, 5(1), 16; https://doi.org/10.3390/magnetochemistry5010016 - 02 Mar 2019
Cited by 6 | Viewed by 3156
Abstract
We briefly summarize the results from a set of experiments designed to demonstrate the effects of high magnetic fields applied during thermal annealing of amorphous Nd2Fe14B produced through melt-spinning. A custom-built differential scanning calorimeter was used to determine the [...] Read more.
We briefly summarize the results from a set of experiments designed to demonstrate the effects of high magnetic fields applied during thermal annealing of amorphous Nd2Fe14B produced through melt-spinning. A custom-built differential scanning calorimeter was used to determine the crystallization temperatures in zero-field and in applied fields of 20 kOe and 90 kOe, which guided subsequent heat treatments to evaluate phase evolution. X-ray diffraction was used for phase identification and transmission electron microscopy was employed for observation of the crystallite size and morphology. Magnetization measurements were also used to evaluate the resulting magnetic phases after thermomagnetic processing. While the applied magnetic fields do not appear to affect the crystallization temperature, significant effects on the kinetics of phase evolution are observed and correlated strongly to the magnetic behavior. Full article
(This article belongs to the Special Issue Permanent Magnets)
Show Figures

Graphical abstract

10 pages, 4176 KiB  
Article
Microstructure and Magnetic Properties of Grain Refined Pr2Co14B Melt-Spun Ribbons
by I. C. Nlebedim, M. Huang, K. Sun, L. Zhou, R. W. McCallum and M. J. Kramer
Magnetochemistry 2019, 5(1), 6; https://doi.org/10.3390/magnetochemistry5010006 - 22 Jan 2019
Cited by 5 | Viewed by 2922
Abstract
The correlation between the grain refining effect of TiC on the microstructure of Pr2Co14B melt-spun ribbons and the magnetic properties is presented in this study. TiC enabled greater control of microstructure both in the as-spun and heat treated Pr [...] Read more.
The correlation between the grain refining effect of TiC on the microstructure of Pr2Co14B melt-spun ribbons and the magnetic properties is presented in this study. TiC enabled greater control of microstructure both in the as-spun and heat treated Pr2Co14B, compared with the material without TiC. As a result, coercivity of the sample with TiC was nearly twice that of the sample without TiC. In addition to Pr2Co14B, two other phases were found in the sample with TiC: one rich in Co and the other having a composition near PrCo2. TiC was found near the grain boundaries and at triple junctions. Also no Ti or C was found in the matrix phase indicating extreme low solubility of the elements when both are present with Pr2Co14B. As expected, both the samples with and without TiC have similar anisotropy field but the presence of room temperature non-ferromagnetic phases (TiC and PrCo2), caused a small decrease in magnetization of the sample with TiC although the romance of the isotropic materials were comparable. Full article
(This article belongs to the Special Issue Permanent Magnets)
Show Figures

Graphical abstract

17 pages, 3405 KiB  
Article
Structural, Magnetic, and Mössbauer Studies of Transition Metal-Doped Gd2Fe16Ga0.5TM0.5 Intermetallic Compounds (TM = Cr, Mn, Co, Ni, Cu, and Zn)
by J. N. Dahal, K. S. Syed Ali, S. R. Mishra and J. Alam
Magnetochemistry 2018, 4(4), 54; https://doi.org/10.3390/magnetochemistry4040054 - 27 Nov 2018
Cited by 10 | Viewed by 3889
Abstract
The effect of transition metal substitution for Fe and the structural and magnetic properties of Gd2Fe16Ga0.5TM0.5 (TM = Cr, Mn, Co, Ni, Cu, and Zn) compounds were investigated in this study. Rietveld analysis of X-ray data [...] Read more.
The effect of transition metal substitution for Fe and the structural and magnetic properties of Gd2Fe16Ga0.5TM0.5 (TM = Cr, Mn, Co, Ni, Cu, and Zn) compounds were investigated in this study. Rietveld analysis of X-ray data indicates that all the samples crystallize in the hexagonal Th2Ni17 structure. The lattice parameters a, c, and the unit cell volume show TM ionic radii dependence. Both Ga and TM atoms show preferred site occupancy for 12j and 12k sites. The saturation magnetization at room temperature was observed for Co, Ni, and Cu of 69, 73, and 77 emu/g, respectively, while a minimum value was observed for Zn (62 emu/g) doping in Gd2Fe16Ga0.5TM0.5. The highest Curie temperature of 590 K was observed for Cu doping which is 15 and 5% higher than Gd2Fe17 and Gd2Fe16Ga compounds, respectively. The hyperfine parameters viz. hyperfine field and isomer shift show systematic dependence on the TM atomic number. The observed magnetic and Curie temperature behavior in Gd2Fe16Ga0.5TM0.5 is explained on the basis of Fe(3d)-TM(3d) hybridization. The superior Curie temperature and magnetization value of Co-, Ni-, and Cu-doped Gd2Fe16Ga0.5TM0.5 compounds as compared to pure Gd2Fe17 or Gd2Fe16Ga makes Gd2Fe16Ga0.5TM0.5 a potential candidate for high-temperature industrial magnet applications. Full article
(This article belongs to the Special Issue Permanent Magnets)
Show Figures

Figure 1

Back to TopTop