2015 IEEE Magnetics Conference (INTERMAG)最新文献

{"title":"Crystal structure and magnetic transition in Fe-Mn-Ga ribbon","authors":"Dongxiang Zhang, H. Zhang, E. Liu, W. Wang, G. Wu, M. Yue","doi":"10.1109/INTMAG.2015.7157273","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157273","url":null,"abstract":"Pure bcc β-phase, fcc γ-phase and hcp phase of Fe-Mn-Ga system have been obtained by melt spinning method and subsequent anneal. It is found that there is a rapid phase transition from β and γ-phase to hcp phase. The β-phase shows a typical low temperature ferromagnetic property, while γ-phase shows a ferromagnetic to antiferromagnetic transition. The newly found hcp phase shows a good ferromagnetic behavior with a relatively high TC, which makes it a possible candidate for hard magnetic material.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128035644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of low-noise three-axis magnetometer with tunneling-magnetoresistance sensors","authors":"V. Luong, J. Jeng, B. Lai, C. Lu","doi":"10.1109/INTMAG.2015.7156761","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7156761","url":null,"abstract":"Three dimensional magnetic sensors play important roles for multiple applications, e g position sensing, automotive application, and geomagnetic navigation [1]. In recent decades, many groups developed various kinds of vector magnetometer [2-8], including Hall effect [3] [6-7], the anisotro-pic magnetoresistance (AMR) effect [8], giant magnetoresistance (GMR) sensors [5], and tunneling magnetoresistance (TMR) magnetometer [2]. For all the designs, the inaccuracy in alignment of sensors or flux-guide leads to non-orthogonality between each sensing directions Another issue on three-axis magnetometer is to achieve a low-noise without increasing the size too much. In order to deal with this issues, several extrinsic methods have been reported, e g TMR arrays [9], flux concentrator [10], and flux-chopping techniques [11]. Interestingly, the 1/f noise can be reduced by a factor of 12 with a shielding type magnetic flux chopper, which was realized successfully in the ref [12]. In this work, we design and manufacture a low-noise vector magnetometer comprising three TMR sensors orthogonally aligned and placed in the central of a shielding flux chopper The non-orthogonality issue can be solved by the calibration process using a voltage-to-field transfer matrix [13].","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"128 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128138117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of electromagnetic torque in permanent magnet synchronous machines with fractional slot concentrated winding","authors":"J. Li, J. Zou, Y. Xu","doi":"10.1109/INTMAG.2015.7157801","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157801","url":null,"abstract":"Electric Machine is an energy conversion device, which realizes the electrical energy and mechanical energy convert to each other through electromagnetic power or electromagnetic torque. Electromagnetic torque is an important medium for this conversion progress. Thus accurate estimation or model of electromagnetic torque is desired for designing and analyzing the electric machines. Furthermore electromagnetic torque estimation for servo control and torque ripple depress, where the model of torque is utilized directly or indirectly, is urgent.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128154994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electric field manipulated nonvolatile and reversible 90°-rotation of the magnetic easy-axis in LSMO/PMN-PT (011) multiferroic heterostructures","authors":"W. Zhao, S. Yang, W. Huang, L. Feng, Dongxiang Zhang, Q. Hu, Y. Yin, S. Dong, X. Li","doi":"10.1109/INTMAG.2015.7156527","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7156527","url":null,"abstract":"Using pure electric voltages instead of magnetic fields or large currents to manipulate magnetisms in multiferroic heterostructures is a goal for future low-power spintronics such as electric-writing magnetic-reading memories. Usually, the electric manipulation to magnetism shows a volatile effect which cannot be used for information storage,[1] because the magnetic variation vanishes after the electric field removal. Recently, the piezostrain-mediated non-volatile 90° and 180° magnetization rotations are realized in the Co/0.7Pb(Mg_1/3Nb_2/3)O₃-0.3PbTiO₃ multiferroic heterostructures at room temperature.[2] However, the non-volatile magnetization rotations in perovskite manganese systems, which are of significance for the design of perovskite magnetic random access memories such as perovskite magnetic tunneling junctions, are still rarely studied. Here we report an in-situ electric field manipulated nonvolatile and reversible 900-rotation of the magnetic easy-axis (MEA) in La_0.7Sr_0.3MnO₃/0.7Pb(Mg_1/3Nb_2/3)O₃-0.3PbTiO₃ (LSMO/PMN-PT) multiferroic heterostructure.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125619190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of novel skewed rotor in squirrel-cage induction motor on electromagnetic force and vibration characteristics","authors":"L. Wang, X. Bao, C. Di, J. Li","doi":"10.1109/INTMAG.2015.7157420","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157420","url":null,"abstract":"In rotating-field machines, especially in squirrel-cage induction motor, the rotor slots are often assembled in a skew position in order to reduce the influences of permeance harmonics caused by slots [1]; Moreover, induction motor suffers from the vibration and acoustic noise from radial electromagnetic force produced by harmonic field [2]. However, besides the rotary torque, torque of axial component is also generated in rotating machines. Former skewed rotor designs fail to solve those problems. In this paper, a novel skewed rotor is proposed, which can offset the axial component of electromagnetic force. Besides, the ill-effects of the electromagnetic force wave to rotor will be reduced or offset, thus the vibration of the rotor and the noise of the motor will be decreased, which in return further optimizes the air gap flux density. The effects of the novel skewed rotor on air-gap magnetic flux density, torque and radial electromagnetic force characteristics in a squirrel-cage induction motor are investigated.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"400 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115918075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical simulation of forces in an ironless planar actuator","authors":"M. J. Susin, A. F. Flores Filho, D. Dorrell","doi":"10.1109/INTMAG.2015.7157478","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157478","url":null,"abstract":"An electromagnetic planar actuator can be described as a device that produces movement on a plane and provides movement with a minimum of two degrees of freedom within an area of movement over that plane [1]. The concept of a planar actuator with an ironless armature is explored in this work. The device is based on a double mover with two pairs of two high-energy NdFeB permanent magnets. They produce a bidirectional movement over the plane formed by the armature with orthogonal windings. This is due to the interaction with the currents in the windings. Its topology is represented in Fig.1 (a). It consists of multiphase windings that are arranged to form two sets of orthogonal windings, i.e., a group of coils assembled in the x-axis forming the x-axis multiphase winding and the group of coils assembled in the y-axis forming the y-axis multiphase winding. Each layer of those multiphase windings is electrically isolated from the other, and each multiphase winding is divided into 6 independent coils or phases.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131459219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The volatile and nonvolatile magnetization switching of CoNi thin films manipulated by electric-field","authors":"T. Jin, J. Cao, L. Hao, M. Liu, Y. Wang, D. Wu, F. Wei","doi":"10.1109/INTMAG.2015.7157310","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157310","url":null,"abstract":"Multiferroic and magnetoelectric materials have attracted significant scientific interest due to their potential application in magnetic information storage devices and magnetic sensors . In those materials, magnetization state could be controlled by using electric-field (E-field), which paves a new way for novel memory devices . In this work, we observe a giant reversible magnetization and magnetic anisotropy reorientation in a magnetoelectric heterostructure, consisting of polycrystalline CoNi thin film and (011)-oriented Pb(Mg1/3Nb2/3)O3-xPbTiO3(PMN-xPT) single crystal . Taking the different piezoelectric response of PMN-PT with different PbTiO3 content, volatile and nonvolatile magnetization switching have been demonstrated in CoNi/PMN-PT heterostructures . The CoNi films were deposited on single crystal PMN-PT substrate by a magnetron sputtering system at room temperature . The composition of CoNi layer was optimized to Co23Ni77, which shows a large magnetostriction coefficient and good soft magnetic properties . In this work, two kind of PMN-PT substrate with 30% PbTiO3 (here after denoted PMN-30%PT) and 32% PbTiO3 (PMN-32%PT) were used . The magnetic properties of the sample under different E-fields were measured by using a vibrating sample magnetometer (VSM) . For CoNi/PMN-30%PT heterostructure, the as-deposited film shows almost in-plane isotropic magnetic properties, as shown in figure 1(a) . With increasing E-field, due to the E-field induced compressive strain along x[100] direction and negative magnetostriction coefficient of CoNi, the y[0-11] direction becomes more and more harder to magnetize . Under a 10kV/cm E-field, the saturation field along y[0-11] direction reaches up to 350Oe and the normalized remanence (Mr/Ms) decreases to 1 .7% . The continuous Mr/Ms vs E-fields loop (figure 1(c)) shows a typical butterfly-shape behavior, indicating that the anisotropy change is almost volatile, which is consistent with the strain vs E-field (figure 1(d)) . For PMN-32%PT substrate, as shown in figure 2(a), the strain response along [0-11] direction is neglectable, while along [100] direction it shows large compressive strain under large E-field . When the E-field returns from 10kV/cm to zero, a large remnant strain (-2200ppm) is obtained, suggesting the E-filed induced strain is nonvolatile . As a result, the corresponding magnetic anisotropy change and magnetization switching in CoNi/PMN-32%PT structure, as shown in figure 2(b,c,d), is also nonvolatile . A minor loop shown in figure 2(d) suggests that when the E-field return from different polarization states (5kV/cm and -2kV/cm) back to zero, two different Mr/Ms values (0 .35 and 0 .73) are obtained . Based on the nonvolatile magnetization switching in CoNi/ PMN32%PT structure, we demonstrate two stable magnetization states manipulated by alternately E-field pulse . In summary, the giant E-field induced volatile and nonvolatile magnetization switching has been observed in CoNi/PMN-PT he","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132127393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of static and dynamic eccentricities in a permanent magnet motor by monitoring BEMF","authors":"K. Kang, S. Sung, J. Song, B. Seo, G. Jang","doi":"10.1109/INTMAG.2015.7156821","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7156821","url":null,"abstract":"One of the major faults of electric motors is a breakdown of bearing because it is the most flexible component under cyclic loading between stator and rotor. Most of bearing faults in electric motors result from localized defect of bearing and generate vibration and noise, which eventually degrades the performance of motor-driven systems. Many researches have been proposed various methods to detect bearing faults by measuring vibration and noise. In electrical point of view, bearing fault changes static and dynamic air gap, which change magnetic field and input current of electric motors. Several researchers studied the diagnostic technique of motor faults by monitoring vibration and current. However, another possible signal of electric motors due to static and dynamic eccentricities is back electromotive force (BEMF) and this research proposes a method to detect static and dynamic eccentricities of a permanent magnet (PM) motor by measuring BEMF. It derives mathematical equations of BEMF due to static and dynamic eccentricities of a PM motor, and performed experiment to validate the derived equations.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"3 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132408028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Fe on hydrogenation and dehydrogenation of Sm(CobalFexCu0.053Zr0.02)7.84(x=0.2,0.3,0.4,0.5) alloys","authors":"M. Li, Z. Liu, L. Lei, Z. Xue, S. He, R. Chen, D. Lee, X. Liu, A. Yan","doi":"10.1109/INTMAG.2015.7157027","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157027","url":null,"abstract":"Hydrogen decrepitation as a highly efficient and excellent crushing method is widely used in the preparation of NdFeB magnets. However, this method still exist many difficulties in the industrial preparation for 2:17 type SmCo alloys owing to high hydrogen pressure. Our previous work has reported 2:17 type SmCo alloys occur HD at room temperature and hydrogen pressure of 0.3 MPa and has shown that Fe atom improved hydrogenation decrepitation ability of alloys by improving hydrogen-absorbing ability of 1:7 phase. But the mechanism that Fe improve hydrogen-absorbing ability of the 1:7 phase still need further study. In addition, subsequent degassing behaviour of alloys have been studied by using DSC.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130142224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of magnet behaviors within high frequency field and high temperature using micromagnetic simulator","authors":"F. Akagi, Y. Honkura","doi":"10.1109/INTMAG.2015.7157717","DOIUrl":"https://doi.org/10.1109/INTMAG.2015.7157717","url":null,"abstract":"Bonded magnets are some of the most industrially important permanent magnets. They enables to complex shapes to be achieved and are stronger than other magnets. NdFeB anisotropic bonded magnets are used in motors of automobiles and magnetic hard disks and sensors utilized in a wide variety of products. In the future, bonded magnets will be needed for motors of hybrid vehicles (HV) and electric vehicles (EV), which are anticipated to become smaller and have higher rotational speed. However, we are concerned that a high frequency field of 10 kHz and high temperature will demagnetize the magnets. This demagnetization will also depend on a static DC-field about 3-4 kOe. We call this demagnetization phenomena `magnetic fatigue'. In this study, magnet behaviors within the high frequency field and at high temperature were simulated using a micromagnetic simulator.","PeriodicalId":381832,"journal":{"name":"2015 IEEE Magnetics Conference (INTERMAG)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134085380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}