KwangSoo;YOON JungHee;RYU DaeWon;KOO

作者:LEE JinWuk;LIM KwangSoo;YOON JungHee;RYU DaeWon;KOO

BongHo;KOH EuiKwan;HONG ChangSeop;
关键词:tungsten, manganese, cyanide, crystal structure, single-

chain magnet
单位:Department of Chemistry, Research neodymium magnet Institute for Natural

Sciences, Korea University, Seoul 136-713, Korea;Nano-Bio System

Research Team, Korea Basic Science Institute, Seoul 136-713,

Korea;
摘要:Reaction of unique [W(CN)6(phen)]- http://www.everbeenmagnet.com with a magnetically

anisotropic Mn Schiff base yielded a WⅤ(5d)-MnⅢ(3d) bimetallic

compound with a linear chain structure. The magnetic properties

of the chain complex feature a ferrimagnetic behavior as well as

slow magnetic relaxation typical for a single-chain magnet.

calixarene, lanthanides, single molecule magnet,

关键词:calixarene, lanthanides, single molecule magnet,

photoluminescence
摘要:The syntheses, crystal structures, magnetic and luminescent

properties of three isomorphous compounds [Ln III 6 (μ 4-O) 2

(C4A) 2-(NO 3 ) 2 (HCOO) 2 (CH 3 O) 2 (DMF) Neodymium mIknatIslar 4 (CH 3 OH) 4 ] (Ln =

Gd (1), Tb (2) and Dy (3); H 4 C4A = p-tert-butylcalix[4]arene)

are reported. These three compounds http://turkey.chinamagnets.biz are featured with the

sandwich-like units constructed by two tail-to-tail calixarene

molecules and an in-between Ln III 6 octahedron. The Dy III

compound exhibits both single molecule magnet behavior and

photoluminescence.

作者:刘武;陈文元;张卫平;黄晓刚;张忠榕;
关键词:diamagnetic levitation; permanent magnet; micro-electro-mechanical systems (MEMS)
单位:Research Inst.of Micro-Nano Science and Technology Shanghai Jiaotong Univ.,Research Inst.of Micro-Nano Science and Technology,Shanghai Jiaotong Univ.,Research Inst.of Micro-Nano Science and Technology,Shanghai Jiaotong Univ.,Research Inst.of Micro-Nano Science and Technology,Shanghai Jiaotong Univ.,Research Inst.of Micro-Nano Science and Technology,Shanghai Jiaotong Univ.,,Shanghai 200030,China,Shanghai 200030,China,Shanghai 200030,China,Shanghai 200030,China,Shanghai 200030,China
摘要:A novel micro-machined diamagnetic stable levitation system (MDSLS) which is composed of a free permanent magnetic rotor, a ring lifting permanent magnet and two diamagnetic stabilizers was presented. The static and dynamic stable characters of MDSLS were analyzed. The coupled non-linear differential equations were used to describe six-degree-of-freedom motion of the levitated rotor, and the equivalent surface current and combined diamagnetic image current method were utilized to model the interaction forces and torques between the lifting permanent magnet and rotor permanent magnet and also between the rotor permanent magnet and diamagnetic substrates. Because of difficulty to get analytical solution, the numerical calculation based on Runge-Kutta method was used to solve the dynamic model. The vibration frequencies were identified by fast Fourier transform (FFT) analysis. According to their resonance characteristics and parameters, the translational and angular dynamic stiffness were also calculated. The results show that the levitation of the rotor in MDSLS is stable, and the MDSLS is potential for the application in levitation inertial sensor.

Fe-Cr-Co-V-Ti permanent magnets

作者:齐凤春
单位:Department of Physics, Dalian Institute of Technology
摘要:<正> Fe-Cr-Co-V-Ti permanent magnets magnetic materials
http://www.999magnet.com are characteristically

free of harmful phase as V contributes to enlarging the α phase

region. At an earlier date, the V content was fixed at 3～5％(wt

％)(Kaneko, H. et al., 1976 and 1978), its B_r and (BH)_(max)

values approach the level of semi-columnar crystal AlNiCO5

magnets, but its H_c value was less than 48.0 kA/m (600 Oe).

However, we later found that the efficient content of V might be

reduced

Sm-Co permanent magnet

作者:顾菡珍,叶于浦
关键词:北京大学:4824,新金属材料:4424,钢铁研究:4407,化学系:3824,伪

口:3617,科学通报:3164
单位:Department of Chemistry, Peking neodymium price
http://www.999magnet.com/products/142-neodymium-price University





,Department

of Chemistry, Peking University
摘要:<正> The fact that the reduction-diffusion procedure can be

used to prepare Sm-Co permanent magnet of high quality is well

known. In order to simplify the technology, as well as to provide

sufficient data for exploring new-type permanent magnets and

other metallic materials (e. g. hydrogen-storage material, etc.)

on basis of rareearth metals, a further investigation on the

process of reduction-diffusion was carried out in the present

work.

Nd2Fe14B/α-Fe, nanocomposite magnets

关键词:3DAP, Nd2Fe14B/α-Fe, nanocomposite magnets, cluster.
摘要:With the fast development in nano ma- terials, to obtain the detailed microstructure informa- tion, microscopes with much higher resolution than the conventional ones are required. A neodymium price
http://www.999magnet.com/products/142-neodymium-price three-dimen- sional atom probe (3DAP), an instrument with near- atomic resolutions of about 0.06 and 0.2 nm in depth and transverse direction, respectively, has been em- ployed to map out the elemental distribution of some conductive materials within a nano-scale volume. This instrument is fit to analyze the elemental distri- bution in nano materials and nano precipitation in common materials. 3DAP is applied to investigate the microstructure of Nd2Fe14B/α?Fe nanocomposite magnets. B, Fe-enriched, Zr-enriched and Nd, Fe-enriched clusters have been found, which cannot be identified by any other instrument.

Pr-Co magnets; Phase transformation; Magnetic properties

关键词:Pr-Co magnets; Phase transformation; Magnetic properties; Mechanical alloying
摘要:<正>PrCo5-based nanograin PrxCo100-x (x=14~22) alloys with high coercivity were synthesized by mechanical alloying Neodymium Magnets
http://www.999magnet.com/products/110-sintered-neodymium-magnets and subsequent annealing. The crystallization, phase components and magnetic properties of the alloys were investigated systematically. The main phase of the alloy for x=14 is Pr2Co17 with rhombohedral Th2Zn17-type. The amount of the Pr2Co17 phase decreases with increasing Pr content, and a nearly single phase PrCo5 with hexagonal CaCu5-type is formed in Pr19Co81 alloy. Further increase in the Pr content leads to the formation of another magnetically hard Pr2Co7 phase with its Curie temperature about 350℃. Remanences decrease monotonously with increasing Pr content, whereas the coercivities increase, reaching a maximum of 2040 kA/m (25.6 kOe) in Pr19Co81 powders milled for 5 h and annealed at 973 K for 2 min, and then decrease for higher Pr content. The high coercivity is attributed to the high anisotropy field of the PrCo5 phase and its nanoscale grain size.

finite element method; rare earths

作者:张宏伟,荣传兵,杜晓波,张绍英,沈保根
关键词:micromagnetic; finite element method; rare earths
单位:State Key Laboratory of Magnetism,State Key Laboratory of Magnetism,State Key Laboratory of Magnetism,State Key magnetic materials
http://www.999magnet.com Laboratory of Magnetism,State Key Laboratory of Magnetism  Institute of Physics and Centre for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, China








, Institute of Physics and Centre for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, China








, Institute of Physics and Centre for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, China








, Institute of Physics and Centre for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, China








, Institute of Physics and Centre for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, China
摘要:The demagnetization curves were calculated using micromagnetic finite-element method for nanocomposite Pr  2Fe    14B/α-Fe permanent magnets with precipitate-typed microstructure. Due to intergrain exchange coupling, both remanence enhancement and a single magnetic phase behavior in demagnetization curve were found. For the samples with the hard phase as the precipitate and the soft one as the matrix, a coercivity μ  0H  c of 0.78 T, a remanence J  r of 1.18 T and a large energy product (BH)    max of 200 kJ·m  -3 are obtained for the sample with hard grain size being 23 nm. While, for the sample with the soft phase as the precipitate, μ  0H  c of 0.95 T, J  r of 1.24 T and (BH)    max of 240 kJ·m  -3 are obtained for the sample with soft grain size being 10 nm. The calculating results were compared with the experimental Pr  8Fe    87B  5 ribbons. The dependence of remanence and coercivity on the microstructure was discussed extensively.

metal materials; exchange coupled

作者:倪建森,徐晖,朱明原,李强,周邦新,董远达
关键词:metal materials; exchange  coupled; two phase nanocrystalline; bonded permanent magnet; rare earths
单位:Institute of Materials,Institute neodymium standard state
http://www.999magnet.com/products/112-neodymium-standard-state of Materials,Institute of Materials,Institute of Materials,Institute of Materials,Institute of Materials Shanghai University,Shanghai 200072,China









,Shanghai University,Shanghai 200072,China









,Shanghai University,Shanghai 200072,China









,Shanghai University,Shanghai 200072,China









,Shanghai University,Shanghai 200072,China









,Shanghai University,Shanghai 200072,China
摘要:Nanocrystalline Nd    8.5  Fe    75  Co  5Cu  1Zr  3Nb  1B    6.5   ribbons were prepared by melt  spun (18 m·s    -1  ) and subsequent heat treatment (670 ℃/4 min). Excellent magnetic properties of the bonded magnet were achieved as follows:    B    r=0.68 T (6  8 kGs),       J  H    c=620.3 kA·m    -1  (7.8 kOe), (  BH  )    max  =74 kJ·m    -3   (9  3 MGOe). The results of TEM photomicrographs confirm that the appearance of α  Fe phase is earlier than that of Nd  2Fe    14  B phase during crystallization process. The addition of Cu and Zr elements shows to be advantageous to the improvement of an intrinsic coercivity and squareness of hysteresis loop, as well as energy product.

metal materials; bonded magnet

作者:孙爱芝,李智伟,韩景智,李涛,张正义,肖耀福
关键词:metal materials; bonded magnet; compression molding; lubricant; strengthener; rare earths
单位:Department of Materials, magnetic materials
http://www.999magnet.com University of Science and Technology Beijing,FEW  DAEWOO (Yantai) Automobile Engine Co. Ltd.,Department of Materials, University of Science and Technology Beijing,Department of Materials, University of Science and Technology Beijing,Department of Materials, University of Science and Technology Beijing,Department of Materials, University of Science and Technology Beijing  Beijing 100083, China









, Yantai 264006, China









, Beijing 100083, China









, Beijing 100083, China









, Beijing 100083, China









, Beijing 100083, China;
摘要:The phenomenon of uneven density distribution is inevitable in the process of preparing bonded magnets with complicated shape or with large geometric size by compression molding due to the friction among magnetic powder grains and between magnetic powder and the die wall, which reduces the pressure along the compression direction. In order to improve the density distribution homogeneity, the thin  wall rings with composition of HDDR NdFeB prepared by compression molding were selected as the investigated object in this study. It was systematically investigated on the effect of addition level of lubricants and the addition methods of lubricants and strengthener on magnet density, density distribution and on magnet strength. By means of joint addition of lubricants and strengthener, which increases the magnet density and improves the magnet density distribution under the precondition of keeping the magnet strength unreduced. Thus the moldability of the bonded magnets is improved.

Synchrotron radiation light source

关键词:Synchrotron radiation light source, Electron storage ring, Magnet lattice
摘要:<正> The Shanghai Synchrotron Neodymium Magnets
http://www.999magnet.com/products/110-sintered-neodymium-magnets Radiation Facility (SSRF) is a proposed 3rd generation light source with 3.5 GeV in energy. It is composed of 20 DBA celis resulting in a ring that is about 10 nm-rad in emittance and 396 m in circumference, and provides 10 straight sections of 7.24 m and other 10 straight sections of 5.0 m for the inclusion of insertion devices, injection components and RF cavities. The lattice has high flexibility, and the tunes and beta func-tions can be easily adjusted within a wide range to meet the requirements for different operation modes, including high beta mode and hybrid beta mode with and/or without dispersion in straight sections. In this paper, the results of linear optics design and dynamic aperture study are presented.

nanocomposite; Nd 2Fe 14 B; melt spun ribbons

作者:白飞明,姜忠良,陈秀云,马春来,朱静
关键词:nanocomposite; Nd  2Fe    14  B; melt  spun ribbons; interaction; rare earths
单位:School of Materials magnetic materials
http://www.999magnet.com Science & Engineering, Tsinghua University,School of Materials Science & Engineering, Tsinghua University,School of Materials Science & Engineering, Tsinghua University,School of Materials Science & Engineering, Tsinghua University,School of Materials Science & Engineering, Tsinghua University Beijing 100084,China









,Beijing 100084,China









,Beijing 100084,China









,Beijing 100084,China









,Beijing 100084,China
摘要:Effect of multiple alloying elements (Ga, Nb, Zr, Hf and Pr) on microstructure and magnetic properties of nanocomposite Nd    9-  x    Pr    x  Fe    86.5-  y-z-m-n    Ga    y  Nb    z  Zr    m  Hf    n  B    4.5   (  x  =0, 2  25;   y, z, m, n  =0.5, 1.0) ribbons was investigated by a L    16  (2    15  ) orthogonal experiment. The results show that the addition of multiple alloying elements can effectively reduce the grain size of Nd  2Fe    14  B and α  Fe phases and promote amorphous phase to occur at low wheel speed. No inhomogeneous growth of grains was found in annealed ribbons, but a large amount of additives would results in irregularity of Nd  2Fe    14  B and α  Fe grains. On the other hand, addition of multiple alloying elements has complex effects on magnetic properties due to interactions between alloying elements. When the content of Nb is 0.5%, increasing the content of Pr and Ga and decreasing the content of Zr and Hf can improve the magnetic properties effectively. The optimum magnetic properties were obtained in Nd    2.25  Pr    6.75  Fe    84.5  Ga    1.5  Nb    0.5  B    4.5   ribbons spun at 15 m·s    -1   with   J    r=1.053 T,       i  H    c=530.9   kA·m    -1    ,(  BH  )    max  =124 kJ·m    -3  .

rare earths; NdFeB sintered magnets

作者:张深根,李红卫,赵进松,于敦波,徐静,张耀
关键词:rare earths; NdFeB sintered magnets; high performance
单位:General Research Institute for Non-Ferrous Metals, Grirem Advanced Materials Corporation Limited,General Research Neodymium Magnets
http://www.999magnet.com/products/110-sintered-neodymium-magnets Institute for Non-Ferrous Metals, Grirem Advanced Materials Corporation Limited,General Research Institute for Non-Ferrous Metals, Grirem Advanced Materials Corporation Limited,General Research Institute for Non-Ferrous Metals, Grirem Advanced Materials Corporation Limited,General Research Institute for Non-Ferrous Metals, Grirem Advanced Materials Corporation Limited,General Research Institute for Non-Ferrous Metals, Grirem Advanced Materials Corporation Limited Beijing 100088, China









,Beijing 100088, China









,Beijing 100088, China









,Beijing 100088, China









,Beijing 100088, China









,Beijing 100088, China
摘要:High energy products (BH)    max of 365 and 310 kJ·m    -3 with intrinsic coercivity     iH  c of   1640 kA·m    -1 of NdFeB sintered magnets were produced. Some new techniques were applied, such as thin NdFeB ingot technique, narrow particle distribution on jet mill, low oxygen content control and high aligned magnetic field press. It is necessary to produce thin NdFeB ingot with fine flake crystal, narrow particle distribution, the average size of NdFeB powders less than 4.0 μm, uniform microstructure, high oriented Nd  2Fe    14B small grains, and finally high performance NdFeB sintered magnets were prepared.

rare earths; hot deformation

作者:陈秀云









,姜忠良









,高天明









,吴严









,杨昌平









,朱静
关键词:rare earths; hot deformation; neodymium prices
http://www.999magnet.com/products/142-neodymium-prices anisotropy; sintering
摘要:The relationship between the microstructures and magnetic properties of rare earth cast permanent  Pr  Fe  B  Cu alloys by hot deformation was studied. Fine and well  aligned column grains can be obtained by using a proper solidification mould with a high cooling rate. The soft magnetic phase α  Fe  can be removed during proper annealing treatment. Hot pressing can produce the anisotropy and refine the grain size, so that the magnetic properties are greatly improved. The technique has the advantages of simple processing, low cost and high benefit, compared with the common sintering processing. Under the condition of the deformation temperature of 1073 K, 90% strain and strain rate of 40×10    -3   s    -1  , the magnetic properties obtained are:   B    r=1.05 T,   i  H    c=955 kA·m    -1  , (  BH  )    max  =207 kJ·m    -3  .

Pulsed magnetic field

关键词:Magnetic probe;;Integrator;;Pulsed magnetic field;;LabVIEW
摘要:<正>This paper describes the magnetic field measurement

system for pulsed magnets in SSRF.The system consists of magnetic

probes,analog active integrator,http://www.999magnet.com oscilloscope,stepper motor and a

controller.An application pro- gram

magnetic materials based on LabVIEW has been

developed as main control unit.After the magnetic field mapping

of a septum magnet prototype,it is verified that the test results

accord with the results of theoretical calculation and computer

simulation.

ddy current,BH magnet,injection,CSNS/RCS

作者:宋金星;康文;霍丽华;郝耀斗;王磊;
关键词:eddy current,BH magnet,injection,CSNS/RCS
单位:Institute of High Energy Physics,Chinese Academy of

Sciences;Graduate University of Chinese Academy of Sciences;
摘要:The injecton pulsed bending bump magnets of Rapid Cycling

Synchrotron (RCS) in China Spallation Neodymium Magnets
http://www.999magnet.com/products/110-sintered-neodymium-magnets Neutron Source (CSNS)

consist of four horizontal bending (BH) magnets and four vertical

bending (BV) magnets.The BH magnets are operated at a repetition

rate of 25 Hz and are excited with a trapezoid rectangle waveform

with about 1.6 milliseconds duration.The eddy current is induced

in BH magnets and in the end plates it is expected to be large,so

the heat generation is of our great concern.In this paper,the

eddy current loss of the BH magnet has been investigated and

calculated by using a coupling method of 3D electromagnetic and

thermal analysis.The accuracy of the analysis is confirmed by

testing the prototype BH magnet.The end plate temperature of the

BH magnet provided with slit cuts has been decreased obviously

and met the requirements.

magnetic properties

作者:胡志华;储林华;李军;刘颖;
关键词:Nd-Fe-B magnets; magnetic properties; the die-upset level;

deformation temperature; spark plasma sintering; rare earths
单位:Department of Materials Engineering, Hubei University of

Automotive Technology;College of Materials Science and

Engineering, Sichuan University;
摘要:The magnetic properties and http://www.999magnet.com/products/125-Magnetic-Separator microstructure of Nd-Fe-B

magnets prepared by spark plasma sintering with different die-

upsetting processes were investigated. The results showed that

the optimum magnetic properties of die-upset Nd-Fe-B magnets were

obtained at 680 ℃ when the die-upset level was 60%, and the

degree of magnetic alignment was 0.84. The microstructures showed

that the coarse grains oc-curred predominantly within certain

areas, and abnormal grain growth was not observed within the

major areas of well-aligned grains. There existed many small

spherical grains, which stacked together and were not aligned

during die upsetting when the deformation temperature was 650 ℃.

These small spherical grains grew up, and were aligned when the

deformation temperature increased from 650 to 680 ℃, which could

improve the crystallographic alignment of die-upset Nd-Fe-B

magnets.

Study on the Control Strategy of Electric Differential of MACCP with Motorized Wheels

Study on the Control Strategy of Electric Differential of MACCP with Motorized Wheels

 The two In-wheels Drive Electric Vehicle (EV) is one of the developing directions for future EVs. Its development has been synchronizing with that of the researching and industrializing of EVs in the word. Because of its perfect controlling performance and potential in engineering applications, more and more efforts have been devoted to the two In-wheels Drive EV by both academicians and engineers alike. The technology of designing and manufacturing in-wheel-motor developed rapidly, and there are many companies specializing on the in-wheel-motor .But it is unsolved for the total vehicle control technology of EV with motorized wheels. The dissertation made an in-depth research on the theory and application of motorized wheels driving for electric vehicle.Firstly, the dynamics simulation mode of MACCP is established in Adams. It includes front double-links independent suspension and rear double-links independent suspension, the rack and pinion steering Neodymium Magnets gear’s pinion and rack, the Fiala model of tire. Base on the model, the simulation desktop of the electric vehicle with motorized wheels is established using Matlab/Simulink and Adams. The desktop can simulate many kinds driving mode of vehicle. It is the foundation for the research in this paper.Secondly, the article author build a small motor dynamometer which is used to open up and design control logic and algorithm of system during period, which gets some important motor parameter algorithm in the test for true the Mini Advance Chassis Control Platform. The platform includes a motor, a photoelectrical encoder, a torque sensor, a magnetic powder brake, frame of motor dynamometer and the hardware circuit of testing system. The measure system is made up of the photoelectrical encoder and the torque sensor, which measure respectively motor speed and torque. After getting the motor speed and torque, the measure system transmits the signal to control motor system.The magnetic powder offers the labor which motor needs. The frame of motor dynamometer links the motor, the photoelectrical encoder, the torque sensor and the magnetic powder brake. The hardware circuit of testing system controls the motor and the magnetic power. On the basis of the small motor dynamometer, we measure http://www.999magnet.com/products/110-sintered-neodymium-magnets permanent magnetic direct current motor’s mechanical features parameter. It offers parameter to motor controller. Because we must know motor’s lag in response time constant. At the same time the small motor dynamometer is the foundation for the research for the later lab’s work.Thirdly, the principle of the electric differential of traditional vehicle and correlative research is introduced and the deficiency is discussed. Consequently, the self-regulation method to realized the electric differential by controlling the torque of the motor and freeing it’s speed is brought out. Using the foregoing simulation desktop, all kinds of driving mode of vehicle running with different wheel speed is simulated. It is proved that the control method is reasonable and feasible by simulation result, all wheels doesn’t skid on all driving mode and the rotation speed matches the wheel center speed by self-adjusting. For knowing whether MACCP can run along the straight line, whetherMACCP can turn around ideal path, we must find a control viable to scout the MACCP’s status. After comparing some kind of scheme, we regard yaw rate as feedback variable. Because (1) When MACCP runs alone straight line, the ideal value of yaw rate is 0. (2) When MACCP runs around , the ideal yaw rate isδ?u/L. In this way we can closed-loop control MACCP through controlling yaw rate.In the paper we regard yaw rate as feedback variable. The conclusion is correct through MACCP running along straight line and turning around ideal path. There are errors between left driving torque and right driving torque, because left motor and right motor are different and motor controller is not accurate. There are errors in process of machining ,manufacture and fit. They will effect MACCP’s manipulating stability and driving stability at the variousroad condition. When MACCP runs along straight line without steering control force, there is a sinusoidal driving moment disturbance on the right driving torque and there is error in MACCP’s kinetic model camber angle. And the camber error is 1o .In such a situation we verify whether MACCP run along straight line. It is proved that through controlling yaw rate we can make MACCP run along the straight line and turn around ideal path.In the vehicle turn course, there is definite friction between each spare of steering system. This kind of friction is reputed the steering system’s dry friction and always reverses with nodal direction of motion. It includes steering system’s dry friction and steering gear’s dry friction. Steering system dry friction is in favor of MACCP’s stability. Without moment of force disturbance, it can reduce MACCP’s eave. When there is the difference between left driving torque and right driving torque, it can cut down the driving torque disturbance. And it can keep MACCP runing along straight line. The dry friction and steering wheel’s aligning torque are main parts of steering wheel helm control moment of force. On the basis of the simulation desktop of the electric vehicle with motorized wheels, all kinds of driving mode of MACCP running is simulated. It is proved that steering system dry friction could increase MACCP’s stability. 更多还原