scholarly journals Investigation on the La Replacement and Little Additive Modification of High-Performance Permanent Magnetic Strontium-Ferrite

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 1034
Author(s):  
Ching-Chien Huang ◽  
Chin-Chieh Mo ◽  
Guan-Ming Chen ◽  
Hsiao-Hsuan Hsu ◽  
Guo-Jiun Shu
Keyword(s):  
High Performance ◽  
Single Phase ◽  
Permanent Magnets ◽  
High Efficiency ◽  
Cobalt Content ◽  
Preparation Condition ◽  
Milling Process ◽  
Experimental Parameters ◽  
La Substitution ◽  
Hard Magnets

In this work, an experiment was carried out to investigate the preparation condition of anisotropic, Fe-deficient, M-type Sr ferrite with optimum magnetic and physical properties by changing experimental parameters, such as the La substitution amount and little additive modification during fine milling process. The compositions of the calcined ferrites were chosen according to the stoichiometry LaxSr1-xFe12-2xO19, where M-type single-phase calcined powder was synthesized with a composition of x = 0.30. The effect of CaCO3, SiO2, and Co3O4 inter-additives on the Sr ferrite was also discussed in order to obtain low-temperature sintered magnets. The magnetic properties of Br = 4608 Gauss, bHc = 3650 Oe, iHc = 3765 Oe, and (BH)max = 5.23 MGOe were obtained for Sr ferrite hard magnets with low cobalt content at 1.7 wt%, which will eventually be used as high-end permanent magnets for the high-efficiency motor application in automobiles with Br > 4600 ± 50 G and iHc > 3600 ± 50 Oe.

scholarly journals Development of optimum preparation conditions of Fe-deficient M-type Ca-Sr System hexagonal ferrites

2020 ◽  
Author(s):  
Ching-Chien Huang ◽  
Mo Chin-Chieh ◽  
Hsiao Tsung-Han ◽  
Lu Sheng-Han ◽  
Tai Yen-Hua ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Low Temperature ◽  
Permanent Magnets ◽  
High Efficiency ◽  
Cobalt Content ◽  
Preparation Condition ◽  
Raw Material ◽  
Preparation Conditions ◽  
Typical Specimen ◽  
Specific Manifestation

Abstract In this work, an experiment was carried out to investigate the preparation condition of anosotropic Fe-deficient M-type Ca-Sr system ferrite with optimum magnetic and physical properties using the raw material Fe2O3 from steel industrial iron oxide waste. The compositions of the calcined ferrites were chosen according to the stoichiometry Ca1 − x−yLaxSryFe10.9CozO19, where x was varied between 0.05 and 0.85, y between 0 and 0.18, and z = 0. The effect of CaO, SiO2 and Co3O4 inter-additives on the Ca-Sr system ferrite was also discussed in order to obtain low-temperature sintered magnets. The optimum condition of making magnets and some properties of a typical specimen are as follows. The preparation condition: condition: composition Ca0.37La0.45Sr0.18Fe10.9Co0O19, calcination condition 1240 °C × 1hr in atmosphere, low-temperature sintering condition 1210 °C × 1hr in atmosphere, inter-additives Co3O4 = 1.85 wt%, CaCO3 = 1.7 wt%, SiO2 = 0.6 wt%, CaO/SiO2 = 1.59. The magnetic properties of Br=5425 Gauss, bHc=4320 Oe, iHc=4602 Oe and (BH)max=5.26 MGOe were obtained for Ca-Sr system hard magnets with relatively low cobalt content. The unremarkable steel industrial iron oxide waste is recycled produce high-end permanent magnets under output power < 1 kW, which will eventually be used in high-efficiency motors. This is a specific manifestation of "garbage turning into gold" and is one of the best models of circular economy.

scholarly journals Permanent Magnet Machines for High-Speed Applications

2022 ◽  
Vol 13 (1) ◽  
pp. 18
Author(s):  
Tianran He ◽  
Ziqiang Zhu ◽  
Fred Eastham ◽  
Yu Wang ◽  
Hong Bin ◽  
...  
Keyword(s):  
Permanent Magnet ◽  
High Speed ◽  
High Performance ◽  
Single Phase ◽  
High Efficiency ◽  
Permanent Magnet Machines ◽  
Advantages And Disadvantages ◽  
Three Phase ◽  
Parasitic Effects ◽  
Rotor Dynamic

This paper overviews high-speed permanent magnet (HSPM) machines, accounting for stator structures, winding configurations, rotor constructions, and parasitic effects. Firstly, single-phase and three-phase PM machines are introduced for high-speed applications. Secondly, for three-phase HSPM machines, applications, advantages, and disadvantages of slotted/slotless stator structures, non-overlapping/overlapping winding configurations, different rotor constructions, i.e., interior PM (IPM), surface-mounted PM (SPM), and solid PM, are summarised in detail. Thirdly, parasitic effects due to high-speed operation are presented, including various loss components, rotor dynamic and vibration, and thermal aspects. Overall, three-phase PM machines have no self-starting issues, and exhibit high power density, high efficiency, high critical speed, together with low vibration and noise, which make them a preferred choice for high-performance, high-speed applications.

The Optimization of Calciothermic Reduction-Diffusion Process for Preparation of High-Performance Sm2Fe17Nx Magnetic Powder

2010 ◽  
Vol 89-91 ◽  
pp. 337-341 ◽  
Author(s):  
Jung Goo Lee ◽  
J.C. Yun ◽  
Jai Sung Lee ◽  
C.J. Choi
Keyword(s):  
Particle Size ◽  
Diffusion Process ◽  
Large Particle ◽  
High Performance ◽  
Single Phase ◽  
Milling Process ◽  
Magnetic Powder ◽  
Large Particle Size ◽  
Magnetic Performance ◽  
Calciothermic Reduction

Calciothermic reduction-diffusion (CRD) method was employed to prepare the Sm2Fe17 powder. By using CRD method, single-phase Sm2Fe17 powders were successfully made and no α-Fe phase detected. And Subsequent suitable nitrogenation treatment after CRD process enabled us to obtain Sm2Fe17Nx magnetic powders. However, the magnetic performance of the powders was below expectation due to their large particle size. Further study on effective milling process is needed.

High-Performance Hardware Interpolation Architecture for High Efficiency Video Coding Decoder

2016 ◽  
Vol 11 (9) ◽  
pp. 764
Author(s):  
Lella Aicha Ayadi ◽  
Nihel Neji ◽  
Hassen Loukil ◽  
Mouhamed Ali Ben Ayed ◽  
Nouri Masmoudi
Keyword(s):  
Video Coding ◽  
High Performance ◽  
High Efficiency ◽  
High Efficiency Video Coding

New hole transport styrene polymers bearing highly π-extended conjugated side-chain moieties for high-performance solution-processable thermally activated delayed fluorescence OLEDs

2021 ◽  
Vol 12 (11) ◽  
pp. 1692-1699
Author(s):  
Ji Hye Lee ◽  
Jinhyo Hwang ◽  
Chai Won Kim ◽  
Amit Kumar Harit ◽  
Han Young Woo ◽  
...  
Keyword(s):  
High Performance ◽  
High Efficiency ◽  
Delayed Fluorescence ◽  
Hole Transport ◽  
Side Chain ◽  
Solution Processed ◽  
Thermally Activated Delayed Fluorescence ◽  
Thermally Activated ◽  
Turn On ◽  
Solution Processable

New polystyrene-based polymers with high π-extended hole transport pendants were synthesized to obtain a low turn-on voltage and high efficiency in solution-processed green TADF-OLEDs.

scholarly journals Neighborhood Energy Modeling and Monitoring: A Case Study

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3716
Author(s):  
Francesco Causone ◽  
Rossano Scoccia ◽  
Martina Pelle ◽  
Paola Colombo ◽  
Mario Motta ◽  
...  
Keyword(s):  
High Performance ◽  
High Efficiency ◽  
Early Stage ◽  
Energy Performance ◽  
Monitoring Plan ◽  
Performance Targets ◽  
Carrier Energy ◽  
Zero Carbon ◽  
Energy Grid

Cities and nations worldwide are pledging to energy and carbon neutral objectives that imply a huge contribution from buildings. High-performance targets, either zero energy or zero carbon, are typically difficult to be reached by single buildings, but groups of properly-managed buildings might reach these ambitious goals. For this purpose we need tools and experiences to model, monitor, manage and optimize buildings and their neighborhood-level systems. The paper describes the activities pursued for the deployment of an advanced energy management system for a multi-carrier energy grid of an existing neighborhood in the area of Milan. The activities included: (i) development of a detailed monitoring plan, (ii) deployment of the monitoring plan, (iii) development of a virtual model of the neighborhood and simulation of the energy performance. Comparisons against early-stage energy monitoring data proved promising and the generation system showed high efficiency (EER equal to 5.84), to be further exploited.

scholarly journals Alloying effect on the order–disorder transformation in tetragonal FeNi

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Li-Yun Tian ◽  
Oliver Gutfleisch ◽  
Olle Eriksson ◽  
Levente Vitos
Keyword(s):  
Transition Temperature ◽  
High Performance ◽  
Density Functional ◽  
Permanent Magnets ◽  
Positive Impact ◽  
Design Strategies ◽  
Alloying Effect ◽  
Functional Theory ◽  
Disorder Transition ◽  
Disorder Transition Temperature

AbstractTetragonal ($${\hbox{L1}}_{0}$$ L1 0 ) FeNi is a promising material for high-performance rare-earth-free permanent magnets. Pure tetragonal FeNi is very difficult to synthesize due to its low chemical order–disorder transition temperature ($$\approx {593}$$ ≈ 593  K), and thus one must consider alternative non-equilibrium processing routes and alloy design strategies that make the formation of tetragonal FeNi feasible. In this paper, we investigate by density functional theory as implemented in the exact muffin-tin orbitals method whether alloying FeNi with a suitable element can have a positive impact on the phase formation and ordering properties while largely maintaining its attractive intrinsic magnetic properties. We find that small amount of non-magnetic (Al and Ti) or magnetic (Cr and Co) elements increase the order–disorder transition temperature. Adding Mo to the Co-doped system further enhances the ordering temperature while the Curie temperature is decreased only by a few degrees. Our results show that alloying is a viable route to stabilizing the ordered tetragonal phase of FeNi.

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