L10 rare-earth-free permanent magnets: The effects of twinning versus dislocations in Mn-Al magnets

2020 ◽  
Vol 4 (9) ◽  
Author(s):  
Yuxiao Jia ◽  
Yuye Wu ◽  
Shuang Zhao ◽  
Shulan Zuo ◽  
Konstantin P. Skokov ◽  
...  
Keyword(s):  
Rare Earth ◽  
Permanent Magnets

scholarly journals Special Issue: Advances in Computational Electromagnetics

2021 ◽  
Vol 7 (6) ◽  
pp. 89
Author(s):  
Valerio De Santis
Keyword(s):  
Rare Earth ◽  
Magnetic Materials ◽  
Permanent Magnets ◽  
Computational Electromagnetics ◽  
Superconducting Materials ◽  
Special Issue ◽  
Full Characterization ◽  
Recent Advances

Recent advances in computational electromagnetics (CEMs) have made the full characterization of complex magnetic materials possible, such as superconducting materials, composite or nanomaterials, rare-earth free permanent magnets, etc [...]

scholarly journals Design of External Rotor Ferrite-Assisted Synchronous Reluctance Motor for High Power Density

2021 ◽  
Vol 11 (7) ◽  
pp. 3102
Author(s):  
Md. Zakirul Islam ◽  
Seungdeog Choi ◽  
Malik E. Elbuluk ◽  
Sai Sudheer Reddy Bonthu ◽  
Akm Arafat ◽  
...  
Keyword(s):  
Rare Earth ◽  
Permanent Magnets ◽  
Design Procedure ◽  
Lumped Parameter Model ◽  
High Power Density ◽  
Analytical Design ◽  
Synchronous Reluctance Motor ◽  
Lumped Parameter ◽  
Reluctance Motor ◽  
External Rotor

The rare-earth (RE) permanent magnets (PM) have been increasingly adopted in traction motor application. However, the RE PM is expensive, less abundant, and has cost uncertainties due to limited market suppliers. This paper presents a new design of a RE-free five-phase ferrite permanent magnet-assisted synchronous reluctance motor (Fe-PMaSynRM) with the external rotor architecture with a high saliency ratio. In such architecture, the low magnetic coercivity and demagnetization risk of the ferrite PM is the challenge. This limits the number of flux barriers, saliency ratio, and reluctance torque. A precise analytical design procedure of rotor and stator configuration is presented with differential evolution numerical optimizations by utilizing a lumped parameter model. A 3.7 kW prototype is fabricated to validate the proposed idea.

Using Chlorine Gas to Recover Rare Earth Metals from End-of-Life Permanent Magnets

JOM ◽  
2021 ◽  
Author(s):  
Valery Kaplan ◽  
Ellen Wachtel ◽  
Konstantin Gartsman ◽  
Yishay Feldman ◽  
Kyoung-Tae Park ◽  
...  
Keyword(s):  
Rare Earth ◽  
End Of Life ◽  
Permanent Magnets ◽  
Rare Earth Metals ◽  
Chlorine Gas

Determination of the shear force of high-coercive permanent magnets from an alloy of neodymium—iron—boron rare-earth elements of 5 mm thickness

2020 ◽  
pp. 7-10
Author(s):  
A.Ya. Krasil'nikov ◽  
A.A. Krasilnikov ◽  
D.V. Taranov
Keyword(s):  
Rare Earth ◽  
Shear Force ◽  
Permanent Magnets ◽  
Magnetic System ◽  
Magnetic Coupling ◽  
Magnetic Systems ◽  
Neodymium Iron Boron ◽  
Magnetic Couplings ◽  
Standard Calculation

The possibility of applying the standard calculation of the shear force of thin high-coercive neodymium— iron—boron permanent magnets in magnetic systems and magnetic couplings is considered. A correction factor is proposed for calculating the shear force in systems with thin magnets, which allows at the stage of developing sealed equipment to calculate the shear force of permanent magnets in these systems. Keywords: magnetic system, magnetic coupling, permanent magnet, shear force. [email protected]

The potential environmental risks associated with the development of rare earth element production in Canada

2021 ◽  
Author(s):  
XIANGBO YIN ◽  
Christine Martineau ◽  
Isabelle Demers ◽  
Nathan Basiliko ◽  
Nicole J. Fenton
Keyword(s):  
Rare Earth ◽  
Rare Earth Element ◽  
Earth Element ◽  
Permanent Magnets ◽  
Indigenous Communities ◽  
Economic Benefits ◽  
Environmental Risks ◽  
Future Research ◽  
Ecological Health ◽  
Climate Conditions

The development of rare earth element (REE) production in Canada could generate significant economic benefits, but also poses serious potential risks to the environment. Rare earth elements have been widely used in modern life and industries, and even are indispensable in some crucial advanced technologies (e.g. permanent magnets). Increasing demand and the context of current US-China trade tensions provide a commercial economic development opportunity for Canada, which has rich resources of REEs, to develop its own sector. However, environmental and health issues caused by REE production are challenges Canada has to face, given that significant environmental impacts have been reported elsewhere (e.g. China). Little literature is available on the potential environmental risks associated with the development of REE production in Canada. It is important to know what environmental issues, particularly those generated by REEs themselves, may happen in Canada in the future. Therefore, three major aspects are evaluated and summarized from multidisciplinary perspectives in this paper: 1) a general conceptual model of the transport of REEs as a group in the environment is established; 2) toxicity levels, biochemical mechanisms, and physiological effects of REEs on different organisms are reviewed, and case-studies from existing REE mining areas are briefly highlighted; and 3) considering specific environmental condition and risk factors, environmental risks Canada may face in future REE developments are identified and discussed. This review concludes with a macro-identification of potential environmental risks associated with the development of REE production in Canada considering both human and ecological health. We note that ingestion, inhalation and dermal exposure for workers and surrounding residents (including potentially indigenous communities), and sub-arctic/arctic climate conditions could increase the risks to human and ecological health in future REE production development in Canada. Finally, future research directions are proposed that could be applied to both Canadian and other geographical contexts.

High temperature oxidation of rare earth permanent magnets. Part 1 – Microstructure evolution and general mechanism

2018 ◽  
Vol 133 ◽  
pp. 374-385 ◽  
Author(s):  
Muhamad Firdaus ◽  
M. Akbar Rhamdhani ◽  
W. John Rankin ◽  
Mark Pownceby ◽  
Nathan A.S. Webster ◽  
...  
Keyword(s):  
Rare Earth ◽  
High Temperature ◽  
Microstructure Evolution ◽  
High Temperature Oxidation ◽  
Permanent Magnets ◽  
General Mechanism ◽  
Temperature Oxidation

scholarly journals Mn-Induced Thermal Stability of L10 Phase in Fept Magnetic Nanoscale Ribbons

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1278
Author(s):  
Alina Daniela Crisan ◽  
Aurel Leca ◽  
Dan Pantelica ◽  
Ioan Dan ◽  
Ovidiu Crisan
Keyword(s):  
Rare Earth ◽  
Single Phase ◽  
Permanent Magnets ◽  
Magnetic Hysteresis ◽  
Ternary Alloys ◽  
Large Temperature ◽  
Nominal Composition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Operation Conditions

Magnetic nanoscale materials exhibiting the L10 tetragonal phase such as FePt or ternary alloys derived from FePt show most promising magnetic properties as a novel class of rare earth free permanent magnets with high operating temperature. A granular alloy derived from binary FePt with low Pt content and the addition of Mn with the nominal composition Fe57Mn8Pt35 has been synthesized in the shape of melt-spun ribbons and subsequently annealed at 600 °C and 700 °C for promoting the formation of single phase, L10 tetragonal, hard magnetic phase. Proton-induced X-ray emission spectroscopy PIXE has been utilized for checking the compositional effect of Mn addition. Structural properties were analyzed using X-ray diffraction and diffractograms were analyzed using full profile Rietveld-type analysis with MAUD (Materials Analysis Using Diffraction) software. By using temperature-dependent synchrotron X-ray diffraction, the disorder–order phase transformation and the stability of the hard magnetic L10 phase were monitored over a large temperature range (50–800 °C). A large interval of structural stability of the L10 phase was observed and this stability was interpreted in terms of higher ordering of the L10 phase promoted by the Mn addition. It was moreover found that both crystal growth and unit cell expansion are inhibited, up to the highest temperature investigated (800 °C), proving thus that the Mn addition stabilizes the formed L10 structure further. Magnetic hysteresis loops confirmed structural data, revealing a strong coercive field for a sample wherein single phase, hard, magnetic tetragonal L10 exists. These findings open good perspectives for use as nanocomposite, rare earth free magnets, working in extreme operation conditions.

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