Permanent magnet rotor e1655961736623.jpeg - @article{osti_1349258, title = {Brushless and Permanent Magnet Free Wound Field Synchronous Motors for EV Traction}, author = {Ludois, Daniel C. and Brown, Ian}, abstractNote = {This final report presents an advanced electric motor design for vehicles. The motor is a wound rotor synchronous machine whose rotor coils are …

 
Rotor (electric) The rotor is a moving component of an electromagnetic system in the electric motor, electric generator, or alternator. Its rotation is due to the interaction between the windings and magnetic fields which produces a torque around the rotor's axis. [1] . Handr block operating hours

Abstract: For the high-frequency permanent magnet electrical machine, a reasonable mechanical aspect design is crucial to meet its stability and reliability. This study focuses on the accurate modelling and analysis of the natural frequencies and modes of the rotor assembly for a designed and manufactured 100 kW 32,000 r/min motor.Abstract: For the high-frequency permanent magnet electrical machine, a reasonable mechanical aspect design is crucial to meet its stability and reliability. This study focuses on the accurate modelling and analysis of the natural frequencies and modes of the rotor assembly for a designed and manufactured 100 kW 32,000 r/min motor.Conventional high-speed flux-switching machines have either a high fundamental frequency or more even harmonics. This paper proposes a novel six-slot four-pole axial flux-switching permanent magnet machine for high-speed applications. The machine, consisting of two radially distributed stators and one rotor, can effectively …The development of high-speed (operating at a rotation speed above 10,000 rpm) synchronous electric machines with permanent magnets is currently a relevant design direction [1,2,3,4,5].The structure of the rotor of synchronous machines with permanent magnets is a system of permanent magnets kept from their radial movement with the …Aug 5, 2020 · To enhance the torque density of a permanent magnet (PM) motor, a rotor overhang structure (OS), which is a simple and effective way to increase the flux linkage, is used in various types of PM motors such as SPM motors [5-9], interior PM motors , and spoke-type PM motors [11, 12]. The OS means that the axial length of the rotor is designed to ... Jan 8, 2021 · The permanent magnet is axially magnetized; meaning that the north and south poles alternate and are on the same axis as the motor shaft. When current is applied to windings, poles on the stator are magnetized and align with the opposite poles from the permanent magnet rotor. For example, north poles would align directly across from south poles. The prototype machine is an axial-flux permanent-magnet machine with a two-rotor–one-stator configuration. The nominal power of the machine is 300 W and the nominal rotational speed is 500 rpm. The magnets are neodymium iron boron magnets. Twelve magnets are mounted on the rotor surface and 12 magnets buried on the rotor (Fig. 12a).Magnetic micro-rotary motors are difficult to build without using magnetic materials or induction 27 because it is difficult to provide reliable sliding electrical contacts to convey currents to the rotor. One form of rotary magnetic motor is similar to that of Figures 6.2.3 and 6.2.4, except that the motor pulls into the segmented gaps a ...Based on the complex structural characteristics of permanent magnet-assisted synchronous reluctance motors (PMA-SynRMs), this paper proposes a multi-objective optimization design method for the motor using a composite algorithm. Firstly, the power density, electromagnetic torque, cogging torque, and torque fluctuation coefficient …Brushless DC electric motor. The motor from a 3.5 in floppy disk drive. The coils, arranged radially, are made from copper wire coated with blue insulation. The rotor (upper right) has been removed and turned upside-down. The grey ring inside its cup is a permanent magnet. This particular motor is an outrunner, with the stator inside the rotor.1 Introduction. Nowadays, high-speed surface-mounted permanent magnet synchronous machines (SPMSMs) are becoming more and more common due to their simple structure, high-power density and high efficiency [1-3].The rare-earth permanent magnets (PMs) are widely applied in the high-speed SPMSMs owing to their high …2.1 Electrical Characteristics. The equivalent circuit of a PMDC motor is shown in Fig. 1. The supply voltage and the current are given. The circuit consists of an induced voltage (Vi) in series with an armature resistor (Rarm) and inductance (Larm). The rotation of the ux generates the induced voltage. Recently, PMSMs having high power density and high efficiency are widely used in premium home appliances and electric vehicles. 1 Compared to a SPMSM (surface-mounted permanent magnet synchronous motor), large torque ripple in an IPMSM is a bad influence on the system in a variable speed range. 2 The optimization of a motor is …rotor. For the rotor, the back iron δ BI and the magnet thicknesses δ PM have to be determined, which will also determine the inner rotor radius. In order to achieve high torque, the rotor should be chosen narrow (leading to a large radius of the magnetic gap, which is the lever arm of the motor). However, the permanent magnets have to provide aRecently, PMSMs having high power density and high efficiency are widely used in premium home appliances and electric vehicles. 1 Compared to a SPMSM (surface-mounted permanent magnet synchronous motor), large torque ripple in an IPMSM is a bad influence on the system in a variable speed range. 2 The optimization of a motor is …The fundamental operation of a permanent magnet motor is like most electric motors; the outer stator holds windings of coils fed by a power source, and the rotor freely rotates based on the forces imparted by the stator coils. Many of the same basic principles for induction motors hold true for permanent magnet motors, and more information can ... high efficiency motors with power-dense permanent magnet rotor materials Arnold manufactures Recoma® 35E, the world’s most power-dense samarium cobalt material available on the market today. This innovative magnetic material is critical to boosting performance in the aerospace, automotive and motorsport industries, providing superior …Jan 8, 2021 · The permanent magnet is axially magnetized; meaning that the north and south poles alternate and are on the same axis as the motor shaft. When current is applied to windings, poles on the stator are magnetized and align with the opposite poles from the permanent magnet rotor. For example, north poles would align directly across from south poles. Since the pole arc coefficient of the rotor permanent magnet is 0.5, according to Ref. 28, the magnetomotive force generated by the permanent magnet is equal to that generated by the adjacent FMP.Jan 24, 2021 · A permanent magnet rotor would be what you want in an application like this. Car alternators don’t use PM rotors bc they need to control rotor current in order to get relatively constant voltage ... Based on the complex structural characteristics of permanent magnet-assisted synchronous reluctance motors (PMA-SynRMs), this paper proposes a multi-objective optimization design method for the motor using a composite algorithm. Firstly, the power density, electromagnetic torque, cogging torque, and torque fluctuation coefficient …In many high-speed electrical machines, centrifugal forces within the rotor can be first-order constraints on electromagnetic optimization. This can be particularly acute in interior permanent magnet (IPM) machines in which magnets are usually retained entirely by the rotor core with no additional mechanical containment. This study …This paper compares two flux-switching machines, namely, one stator permanent magnet flux-switching machine and one rotor permanent magnet flux …A new technique for high performance and robust speed control of permanent magnet synchronous motor (PMSM) using a mixed non-linear H∞ and Sliding Mode Control (SMC) is applied.effects of magnet polarities [18,19], PM number [20], winding configurations[21,22], asymmetrical stator pole [23], stator/rotor combinations [24] etc., and their effects on electromagnetic characteristics have been presented. Further more, investigations of the working mechanism have demonstrated that only fundamental rotor permeance andAxial-flux permanent magnet (AFPM) motors have been attracting great interest due to their key advantages of high-torque density and compact structure. Concentrated windings are commonly used for AFPM motors since they significantly reduce the radial length of the end windings. This paper proposes a novel double-sided stator …In this work we proposed to study the use of permanent magnet synchronous motors (PMSM) for railway traction in the high-speed trains (HST) of Renfe Operadora (the Spanish national railway operator). Currently, induction motors (IM) are used in AVE classes 102–112 trains, so, the IM used as a traction motor in these trains has …High-speed or ultra-high-speed permanent magnet synchronous motors (PMSMs) have a strong trend of application in modern industry due to those simple structures and high power density. 1,2 For high-speed motors or generators, the rotor speed is normally above 30,000 r/min even may exceed 100,000 r/min. Designs of such high …The main objective of this paper is to design and analyze the performance of in-wheel outer rotor permanent magnet synchronous motor (PMSM) used in electric vehicles based on a previously designed ...It should be understood that the “rotor inside” vs. “rotor outside” distinction is in fact trivial, with very few exceptions, which we will note. 2.1 Surface Magnet Machines Figure 1 shows the basic magnetic morphology of the motor with magnets mounted on the surface of the rotor and an otherwise conventional stator winding. Mar 16, 2015 · A post-assembly magnetizing fixture has been designed and successfully used to magnetize the rotor of a 100 kW high speed permanent magnet synchronous motor. The rotor is a solid cylinder with outer diameter of 80 mm and total length of 515 mm. The permanent magnet material is samarium-cobalt (Sm 2 Co 17) with saturation magnetizing field of 6 ... The demagnetization of rotor permanent magnet is described in terms of rotor offset caused by demagnetization, demagnetization angle, decrease of air-gap MMF at the demagnetization …This paper investigates mechanical vibrations of an interior permanent magnet (IPM) synchronous electrical motor designed for a wide range of speeds by virtue of the modal and rotordynamic theory. Mechanical vibrations of the case study IPM motor components were detected and analyzed via numerical, analytical and experimental …Mar 20, 2021 · Reluctance is a function of rotor position in a variable reluctance motor. Sequential switching (Figure below) of the stator phases moves the rotor from one position to the next. The mangetic flux seeks the path of least reluctance, the magnetic analog of electric resistance. This is an over simplified rotor and waveforms to illustrate operation. An internal permanent magnet synchronous machine (IPMSM) was designed for heavy-load traction vehicles applied in port transportation. Based on finite element analysis (FEA), the rotor iron core topology was optimized with the most attention paid to cogging torque and torque ripple. The influences of the iron core on the air-gap …Purpose This paper comprehensively analyses the radial electromagnetic (EM) force by unit area and vibration characteristics in a permanent magnet synchronous motor (PMSM). This provides the possibility to verify the action law, causes, and influencing factors of vibration deformation and provides new ideas for vibration management. …A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, steel, nickel, cobalt, etc. and attracts or repels other magnets. A permanent magnet is an object made from a material ... 2.1 Selection of Solution Variants for Analysis. In this study, an analysis of the selection of the number of stator slots to the number of magnetic poles was carried out for the structure of the Permanent Magnet Synchronous Motor (PMSM) with an external rotor, with surface mounted magnets (SPM) with a double-layer, concentrated winding …When permanent magnet synchronous motor is running at ultra-high speed, the tensile strength of permanent magnet is far lower than the compressive strength, and it is unbearable to withstand the large centrifugal tension caused by rotation. Generally, adding the non-magnetic alloy sleeve outside the permanent magnet is the protective …A stationary magnetic field is produced across the rotor by poles on the stator. These poles may be encircled by field coils carrying direct current, or they may contain permanent magnets. The rotor or armature consists …Choosing the proper engine that fits the desired application is a crucial design factor in robotics. Accordingly, this paper compares different types of engines for other Industrial robots (IR) and proposes to put practical criteria based on the mechanical design and its application. It starts from describing the IR choice to explaining the …1. Introduction. At present, the low-speed high-torque transmission system has vast application prospects in the application fields of ship propulsion, lifting, mining and oil field exploitation [1].Permanent magnet motors can maintain good performance in a wide range of load changes, so they have received extensive attention in low-speed and large …External rotors of “outrunner” type. Rotors with additional bandage (Polyglas, Kevlar, carbon) Rotors with protecting sleeve. Contact us. Jan Kratochvil ml. +420 607 570 823 [email protected]. We will be happy to cooperate on development and manufacturing of rotors with permanent magnets, please contact our specialist. Leave …The development of high-speed (operating at a rotation speed above 10,000 rpm) synchronous electric machines with permanent magnets is currently a relevant design direction [1,2,3,4,5].The structure of the rotor of synchronous machines with permanent magnets is a system of permanent magnets kept from their radial movement with the …@article{osti_1349258, title = {Brushless and Permanent Magnet Free Wound Field Synchronous Motors for EV Traction}, author = {Ludois, Daniel C. and Brown, Ian}, abstractNote = {This final report presents an advanced electric motor design for vehicles. The motor is a wound rotor synchronous machine whose rotor coils are …Permanent Magnet Motors - External Rotor. The W series external-rotor permanent magnet motor combines the high strength alloy material with the patented one-piece fan …1,417 permanent magnets stock photos, 3D objects, vectors, and illustrations are available royalty-free. See permanent magnets stock video clips. Experimental electric generator on white background, consists of copper coils and magnets. A generator is a device that converts mechanical energy to electrical energy for use in an external circuit.Synchronous motor. Miniature synchronous motor used in analog clocks. The rotor is made of permanent magnet. Small synchronous motor with integral stepdown gear from a microwave oven. A synchronous electric motor is an AC electric motor in which, at steady state, [1] the rotation of the shaft is synchronized with the frequency of the supply ... Since the pole arc coefficient of the rotor permanent magnet is 0.5, according to Ref. 28, the magnetomotive force generated by the permanent magnet is equal to that generated by the adjacent FMP.Range of Surface-Mounted Permanent-Magnet. ... 413. [6] M. Hippner and R. G. Harley, 1992, “Looking for. an optimal rotor for high speed permanent magnet. synchronous machine”, Conference Rec ...Aug 17, 2022 · For high-speed permanent magnet machines (HSPMMs), two different rotor structures are widely used: surface-mounted permanent magnet (SPM) and interior permanent magnet (IPM). The two different rotor structures have a large impact on the comprehensive performance in multiple physical fields of HSPMMs, including mechanical stress, electromagnetic characteristics, and temperature distribution ... Permanent Magnet Rotors. Magnetic motor rotor, which is formed by magnetic steel, metal shaft or metal shell. According to detailed application situation, the …A flux-reversal permanent-magnet motor with the magnetic-differential application is presented in this paper. The motor adopts radial-field double-rotor structure. By artfully integrating a set of windings into the motor, the motor is able to realize differential without the bulky differential gear, making the propulsion system in electric vehicles more …The windings of coreless axial flux permanent-magnet machine (CAFPM) are exposed to the rotor magnetic field, where each back electromotive force (EMF) harmonic is induced not only by several ...Axial flux permanent magnet synchronous motors (AFPMSMs) have been widely used in wind-power generation, electric vehicles, aircraft, and other renewable-energy applications owing to their high power density, operating efficiency, and integrability. To facilitate comprehensive research on AFPMSM, this article reviews the developments in …The SPMSM has the permanent magnets fixed on the surface of the rotor leading to a symmetrical radial air-gap reluctance path between the rotor and the stator core. The IPMSM has the permanent magnets inserted inside the rotor core leading to a non-symmetrical radial air-gap reluctance path between the rotor and the stator core. Permanent Magnet (PM) Brushless Direct Current (BLDC) actuators/motors have many advantages over conventional machines, including high efficiency, easy controllability over a wide range of operating speeds, etc. There are many prototypes for such motors; some of them have a very complicated construction, and this ensures their …Yu S B, Tang R. Electromagnetic and mechanical characterizations of noise and vibration in permanent magnet synchronous machines. IEEE Trans Magn, 2006, 42: 1335–1338. Article Google Scholar Zuo S, Lin F, Wu X. Noise analysis, calculation, and reduction of external rotor permanent-magnet synchronous motor.Range of Surface-Mounted Permanent-Magnet. ... 413. [6] M. Hippner and R. G. Harley, 1992, “Looking for. an optimal rotor for high speed permanent magnet. synchronous machine”, Conference Rec ...In a permanent-magnet machine, where the magnets reside on the rotor, there is no secondary winding. However, the permanent magnet can be modeled with a fictitious secondary winding excitation [1,2] and therefore the stator leakage inductance can be defined. Care must be taken that permanent magnets do not get demagnetized due to excessive ... Permanent magnet generator (PMG) for vehicles has attracted more and more attention because of its high efficiency, high power density, and high reliability. However, the weak main air-gap magnetic field can affect the output performance and the normal use of electrical equipment. Aiming at the problem, this paper took the rotor …The equivalent magnetic circuit (EMC) is employed both to design the mechanical parameters of the rotor while considering nonlinear magnetic saturation effect and to analyze the magnetic characteristics of the air-gap of the motor. This paper considers the design and performance evaluation of interior permanent magnet …Nov 11, 2021 · According to the location of permanent magnet on the rotor, the permanent magnet synchronous motor rotor mainly has two different structures: surface-mounted and buried. Due to the strength limitation of silicon steel sheets, the application of buried rotor in the high-speed field is relatively smaller than surface-mounted rotor. In a permanent-magnet machine, where the magnets reside on the rotor, there is no secondary winding. However, the permanent magnet can be modeled with a fictitious secondary winding excitation [1,2] and therefore the stator leakage inductance can be defined. Care must be taken that permanent magnets do not get demagnetized due to excessive ... When the rotor magnets are placed inside the rotor iron in PMSM, the machine is called interior permanent magnet (IPM) . In this case, the magnetic reluctance is not uniform as it was for SM-PMSM. So, the self-inductance value of the stator will depend on the rotor position and, consequently, there will be nonzero reluctance torque in addition to the …This paper investigates mechanical vibrations of an interior permanent magnet (IPM) synchronous electrical motor designed for a wide range of speeds by virtue of the modal and rotordynamic theory. Mechanical vibrations of the case study IPM motor components were detected and analyzed via numerical, analytical and experimental …The rotor of the HSPMSM adopts a solid cylindrical permanent magnet rotor with the parallel magnetization of two poles. The excitation magnetic field of the permanent magnet is a standard sinusoidal magnetic field, which can provide a large magnetic potential, which is convenient for the design of large air gaps and is conducive to …The equivalent magnetic circuit (EMC) is employed both to design the mechanical parameters of the rotor while considering nonlinear magnetic saturation effect and to analyze the magnetic characteristics of the air-gap of the motor. This paper considers the design and performance evaluation of interior permanent magnet …Aug 25, 2020 · Permanent Magnet AC Motors. Like an induction motor, a permanent magnet motor has a Stator configured to provide a number of poles, usually for a 3-Phase supply. However, instead of containing Rotor bars, the Rotor has magnets mounted on, or embedded in, the laminations. These magnets, which are often made from rare earth elements (neodymium or ... The fundamental operation of a permanent magnet motor is like most electric motors; the outer stator holds windings of coils fed by a power source, and the rotor freely rotates based on the forces imparted by the stator coils. Many of the same basic principles for induction motors hold true for permanent magnet motors, and more information can ...An interior permanent magnet synchronous motor (IPMSM) with ‘VV—’ shape rotor topology structure is proposed. The established two-dimensional (2D) parameterized finite element analysis (FEA) models are used to analyze and compare the output average torque, torque density, air-gap flux density and back electromotive force …More specifically, the rotor itself contains permanent magnets, which are either surface-mounted to the rotor lamination stack or embedded within the rotor …The fundamental operation of a permanent magnet motor is like most electric motors; the outer stator holds windings of coils fed by a power source, and the rotor freely rotates based on the forces imparted by the stator coils. Many of the same basic principles for induction motors hold true for permanent magnet motors, and more information can ...In this paper, a novel dual mechanical port dual rotor counter-rotating permanent magnet flux switching generator (DMPDRCR-PMFSG) for wind turbine applications is proposed. Power distribution between the inner and outer rotors of the proposed DMPDRCR-PMFSG that contributes to the cumulative output power is …2.1 Electrical Characteristics. The equivalent circuit of a PMDC motor is shown in Fig. 1. The supply voltage and the current are given. The circuit consists of an induced voltage (Vi) in series with an armature resistor (Rarm) and inductance (Larm). The rotation of the ux generates the induced voltage. Jan 13, 2023 · Structure Review of Inner Permanent Magnet Synchronous machines (PMSM) Radial magnetization pattern can used applied to the permanent magnet motors, motors are in different size and shapes for the different applications. In this section different kind of PM motors will be reviewed. Field Excitation (FE) Permanent Magnet (PM) Hybrid Excitation (HE) Drive motors are the mainstay in our day-to-day life. In drive motors, the Permanent Magnet Brushless DC (PMBLDC) motors are more prominent. It has excellent torque-speed characteristics. Compared to others, it has less maintenance cost. The Cogging torque is one of the crucial obstructions in PMBLDC Motor. It has always been a …Understanding permanent magnet motors. A permanent magnet (PM) motor is an ac motor that uses magnets imbedded into or …

Consequent-pole permanent magnet (CPM) machines have considerable potential for low-cost applications because they can improve the permanent magnet (PM) utilization ratio. However, the phase back electromotive force (EMF) of CPM machines with Ns/(mt) = odd (t is the greatest common divisor of the stator slot number Ns and the …. 11691_audio_galeriia_1

permanent magnet rotor e1655961736623.jpeg

This paper is focused on the optimal design, simulation, and experimental testing of a counter-rotating double-rotor axial flux permanent magnet synchronous generator (CRDR-AFPMSG) for wind turbine applications. For the optimal design of the CRDR-AFPMSG, the particle swarm optimization algorithm to maximize efficiency and …Non−Magnetic Rotor Core Rotor Magnets Rotor Pole Pieces Figure 2: Axial View of a Flux Concentrating Motor The geometry of one type of internal magnet motor is shown …Dec 2, 2022 · This paper presents an analytical method for calculating rotor stresses of high-speed surface-mounted permanent magnet synchronous motors (SPMSMs) with segmented permanent magnets (PMs), the pole-arc coefficient, fillings between poles, and material anisotropy are accurately considered. Afterward, the rotor stresses with different retaining sleeves and fillings are compared, the variation laws ... Choosing the proper engine that fits the desired application is a crucial design factor in robotics. Accordingly, this paper compares different types of engines for other Industrial robots (IR) and proposes to put practical criteria based on the mechanical design and its application. It starts from describing the IR choice to explaining the …1 INTRODUCTION. Due to the outstanding advantages of small size, high power density, low noise and high transmission efficiency, high-speed machine has been widely concerned [].Currently, there are mainly three types of high-speed machines: induction machine, switched reluctance machine and permanent magnet (PM) machine …A high-speed (HS) permanent magnet (PM) synchronous motor (HSPMSM) with a carbon fiber-reinforced plastic (CFRP) protective sleeve in the surface-mounted rotor was explored in this study. In view of retaining the PMs at HS operations, the high-strength CFRP sleeve was designed on the basis of a process that could be summarized as …Conventional high-speed flux-switching machines have either a high fundamental frequency or more even harmonics. This paper proposes a novel six-slot four-pole axial flux-switching permanent magnet machine for high-speed applications. The machine, consisting of two radially distributed stators and one rotor, can effectively …The traditional bearingless synchronous reluctance motor (BSynRM) with salient pole rotor has some drawbacks such as high suspension force ripple, low torque density and low power factor. To overcome the above shortcomings, the permanent-magnet-assisted bearingless synchronous reluctance motor (PMa-BSynRM) is …In this work we proposed to study the use of permanent magnet synchronous motors (PMSM) for railway traction in the high-speed trains (HST) of Renfe Operadora (the Spanish national railway operator). Currently, induction motors (IM) are used in AVE classes 102–112 trains, so, the IM used as a traction motor in these trains has …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 …Mar 29, 2018 · For the high-frequency permanent magnet electrical machine, a reasonable mechanical aspect design is crucial to meet its stability and reliability. This study focuses on the accurate modelling and analysis of the natural frequencies and modes of the rotor assembly for a designed and manufactured 100 kW 32,000 r/min motor. For permanent-magnet (PM) machines, only specific stator MMF harmonic, known as working harmonic, interacts with the PM field to produce continuous electromagnetic torque . Lower and higher order stator MMF spatial harmonics rotating at different speeds to the rotor, will bring about unwelcome effects, such as eddy current …Apr 1, 2023 · The rotor spinning at high speed generates a large tensile stress. Once the yield strength of the permanent magnet (PM) is exceeded, the permanent magnet will be broken. Therefore, a high-strength sleeve must be installed outside the permanent magnet [3, 4]. Many researchers have conducted extensive study on rotor strength analysis of HSPMSM ... Based on the complex structural characteristics of permanent magnet-assisted synchronous reluctance motors (PMA-SynRMs), this paper proposes a multi-objective optimization design method for the motor using a composite algorithm. Firstly, the power density, electromagnetic torque, cogging torque, and torque fluctuation coefficient …reluctance, thus creating a magnetic pull to rotate the rotor. PM motors are driven by the interaction of the magnetic field generated by the permanent magnets and the rotating magnetic field generated by the stator winding. The characteristics of these high-speed motors are shown in Table1[61]. As can be seen from Table1, the high-speed …A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, steel, nickel, cobalt, etc. and attracts or repels other magnets. A permanent magnet is an object made from a material ... .

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