scholarly journals FeCo Nanowire–Strontium Ferrite Powder Composites for Permanent Magnets with High-Energy Products

2020 ◽  
Vol 3 (10) ◽  
pp. 9842-9851
Author(s):  
J. C. Guzmán-Mínguez ◽  
S. Ruiz-Gómez ◽  
L. M. Vicente-Arche ◽  
C. Granados-Miralles ◽  
C. Fernández-González ◽  
...  
Keyword(s):  
Permanent Magnets ◽  
High Energy ◽  
Strontium Ferrite ◽  
Ferrite Powder ◽  
Powder Composites ◽  
Energy Products

scholarly journals Magnetic Properties of SmCo5 + 10 wt% Fe Exchange-Coupled Nanocomposites Produced from Recycled SmCo5

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1308 ◽  
Author(s):  
Arnab Chakraborty ◽  
Răzvan Hirian ◽  
Gregor Kapun ◽  
Viorel Pop
Keyword(s):  
Heat Treatment ◽  
Exchange Coupling ◽  
Permanent Magnets ◽  
High Energy ◽  
Raw Material ◽  
Energy Ball ◽  
Hydrogen Decrepitation ◽  
Energy Products ◽  
First Time ◽  
Recycled Material

Nanostructured alloy powders of SmCo5 + 10 wt% Fe obtained using recycled material were studied for the first time. The SmCo5 precursor was obtained from commercial magnets recycled by hydrogen decrepitation. The results were compared with identically processed samples obtained using virgin SmCo5 raw material. The samples were synthesized by dry high-energy ball-milling and subsequent heat treatment. Robust soft/hard exchange coupling was observed—with large coercivity, which is essential for commercial permanent magnets. The obtained energy products for the recycled material fall between 80% and 95% of those obtained when using virgin SmCo5, depending on milling and annealing times. These results further offer viability of recycling and sustainability in production. These powders and processes are therefore candidates for the next generation of specialized and nanostructured exchange-coupled bulk industrial magnets.

High Coercivity Mechanism Of The Die-Upset Hard Magnets Re13.75Fe80.25B6 (Re = Nd, Pr): Possible Correlation To Specific DefectMicrostructure

1999 ◽  
Vol 5 (S2) ◽  
pp. 42-43
Author(s):  
V.V. Volkov ◽  
Y. Zhu
Keyword(s):  
Magnetic Structure ◽  
Permanent Magnets ◽  
Materials Science ◽  
High Energy ◽  
High Coercivity ◽  
Energy Product ◽  
Hard Magnets ◽  
Energy Products ◽  
Processing Techniques

The magnetic properties of permanent magnets are sensitive to their microstructure. In particular, for the family of Nd(Pr)-Fe-B magnets a very different coercivity and energy products may be obtained by several processing techniques. It was experimentally found that a small excess of Nd over the exact phase composition of Nd2Fe14B plays an important role in obtaining high-energy products during the die-upset processing of the anisotropic hard magnets. However the specific role of the Nd excess on both magnetic structure and microstructure of these die-upset magnets is unclear and controversial. Answers to these questions may help to correctly address some major issues in materials science, e.g. how microstructure is related to magnetic structure of hard magnets, and how to optimize the performance of hard magnets.In-situ TEM magnetizing experiments combined with Lorentz magnetic microscopy in Fresnel-Foucault modes were used to characterize the magnetic structure of die-upset, high energy-product hard magnets Nd13.75Fe80.25B6 and Pr13.75Fe80.25B6.

Permanent Magnet Chatter Absorber with Fuzzy Logic Control

2009 ◽  
Vol 147-149 ◽  
pp. 290-295 ◽  
Author(s):  
Bogdan Broel-Plater ◽  
Stefan Domek ◽  
Arkadiusz Parus
Keyword(s):  
Fuzzy Logic ◽  
Control System ◽  
Fuzzy Control ◽  
Fuzzy Logic Control ◽  
Control Algorithm ◽  
Permanent Magnets ◽  
Practical Experience ◽  
High Energy ◽  
Logic Control ◽  
Machine Operators

The paper deals with semi-active chatter absorber based on an electrodynamic transducer built around high-energy permanent magnets. Also, a fuzzy logic control system for the absorber control system has been designed. The principal advantage of fuzzy control is the possibility to implement practical experience gained by machine operators in the control algorithm. Hence, the possibility of factoring such quantities, as vibrations experienced by selected points of the machine-tool, and sound emitted by working machine into the analyzed chatter absorber fuzzy control system has been studied in the paper. The control system has been tested by way of simulation with the use of the process and cutting force models.

scholarly journals Efficiency estimation for permanent magnets of synchronous wind generators

2014 ◽  
Vol 51 (1) ◽  
pp. 21-31 ◽  
Author(s):  
A. Serebryakov ◽  
N. Levin ◽  
A. Sokolov ◽  
E. Kamolins
Keyword(s):  
Magnetic Field ◽  
Permanent Magnets ◽  
Direct Action ◽  
High Energy ◽  
Electrical Machine ◽  
Maintenance Costs ◽  
Wind Generators ◽  
Efficiency Estimation ◽  
Indirect Action ◽  
Proper Orientation

Abstract Application of wind generators opens wide possibilities for raising the efficiency of low- and medium-power wind generators (WGs). The mass of generators in the proposed version is smaller, their reliability higher, while maintenance costs are lower. At the same time, the use of high-energy permanent magnets in generators of enhanced power comes up against some obstacles, which can be overcome through proper orientation of magnetization at creation of a magnetic field in the airgap of electrical machine. In this regard, it might be preferable to use magnets with indirect action on the airgap instead of those with direct action. A convincing example of the former variant is a generator with tangentially oriented magnetization of permanent magnets. In the work, an attempt is done to prove the advantages of such installation in modern low- and medium-power WGs

scholarly journals A lightweight magnetic gripper for an aerial delivery vehicle: design and applications

ACTA IMEKO ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 61
Author(s):  
Giuseppe Sutera ◽  
Dario Calogero Guastella ◽  
Giovanni Muscato
Keyword(s):  
Energy Consumption ◽  
Permanent Magnets ◽  
High Energy ◽  
Vehicle Design ◽  
Delivery Vehicle ◽  
Delivery Service ◽  
Remote Areas ◽  
Different Types ◽  
Robot Systems ◽  
High Energy Consumption

<p>In recent years, drones have become widely used in many fields. Their vertical flight capability makes these systems suitable for carrying out a variety of tasks. In this paper, the delivery service they provide is analysed. The delivery of goods quickly and to remote areas is a relevant application scenario; however, the systems proposed in the literature use electromagnets, which affect the duration of the flight. In addition, these devices are heavy and suffer from high energy consumption, which reduces the maximum transportable payload. This study proposes a new lightweight magnetic plate composed of permanent magnets, capable of collecting and positioning any object as long as it has a ferromagnetic surface on the top. This plate was developed for the Mohamed Bin Zayed International Robotics Challenge 2020, an international robotics competition for multi-robot systems. Challenge two of this competition required a drone capable of picking up different types of bricks and assembling them to build a wall according to an assigned pattern. The bricks were of different colours and sizes, with weights ranging from 1 to 2 kg. In light of this, it was concluded that weight was the most relevant specification to consider in drone design.</p>

Misch-Metal and/or Aluminum Substitutions in ND-FE-B Permanent Magnets

1987 ◽  
Vol 96 ◽  
Author(s):  
B. M. Ma ◽  
C. J. Willzian
Keyword(s):  
Rare Earth ◽  
Permanent Magnets ◽  
Alloy System ◽  
Magnetic Characteristics ◽  
Al Doping ◽  
Sintered Magnet ◽  
Al Content ◽  
Misch Metal ◽  
Heavy Rare Earth Elements ◽  
Energy Products

ABSTRACTThe effects of misch-metal–and/or Al substitutions in the Nd-Fe-B alloy system have been investigated. Selected compositions were processed into magnets using the conventional powder metallurgy technique. As expected, misch-metal substitutions act to degrade the intrinsic magnetic characteristics and thus degrade the properties of the sintered magnet. It was observed that at a level of 25% of the total rare earth being comprised of misch-metal, energy products of the order of 25 MGOe were still able to be achieved. Processing of such material is difficult because higher sintering temperatures are required to fully densify the magnet, and the grain growth that occurs at these temperatures dramatically reduces the coercivity. The effects of misch-metal substitutions are quantified in this discussion.Al was found to be beneficial for improving the coercivity in both the Nd-Fe-B and misch-metal-Fe-B alloy systems. Unfortunately Al substitutions reduce both the remanence and the Curie temperature. If the Al content is kept to 1 wt.% or less, magnets exhibiting reasonable properties can be made. Al doping as opposed to doping with expensive heavy rare earth elements such as Th or Dy is a less costly method of improving Hei, in the Nd-Fe-B magnets.

scholarly journals Direct-Drive Synchronous Generators with Excitation from Strontium-Ferrite Magnets: Efficiency Improvement

2012 ◽  
Vol 49 (4) ◽  
pp. 3-13
Author(s):  
A. Serebryakov ◽  
N. Levin ◽  
A. Sokolov
Keyword(s):  
Permanent Magnets ◽  
Strontium Ferrite ◽  
Air Gap ◽  
Electric Machine ◽  
Specific Power ◽  
Hard Material ◽  
Efficiency Improvement ◽  
Direct Drive ◽  
Synchronous Generators ◽  
Starting Torque

Direct-Drive Synchronous Generators with Excitation from Strontium-Ferrite Magnets: Efficiency Improvement The authors consider the possibility to raise the specific power of synchronous generators with excitation from inexpensive permanent magnets. For this purpose, it is proposed to use tooth-wise windings and permanent magnets based on inexpensive magneto-hard material, e.g. strontium-ferrite. The magnets are to be placed between the rotor teeth, the alternate polarity of which is facing the air-gap. This provides a simpler and cheaper technology of making such a generator and improves its reliability. The proposed rational bevelling of the stator teeth not only raises the specific power of the generator but also reduces the level of noise and vibrations, extends the longevity of the magnets and bearings as well as facilitates the starting torque of the electric machine, e.g. if it is employed as wind generator.

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