# IEEE Transactions on Magnetics

## Filter Results

Displaying Results 1 - 25 of 31
• ### [Front cover]

Publication Year: 2009, Page(s): C1
| |PDF (245 KB)
• ### IEEE Transactions on Magnetics publication information

Publication Year: 2009, Page(s): C2
| |PDF (39 KB)

Publication Year: 2009, Page(s):5257 - 5258
| |PDF (62 KB)
• ### The Physics of Geomagnetic-Field Transduction in Animals

Publication Year: 2009, Page(s):5259 - 5265
Cited by:  Papers (11)
| |PDF (126 KB) | HTML

Birds, fish, sea turtles, and various other animals have been reported to sense the geomagnetic field and to use it for orientation, navigation, and homing. In recent years, exciting progress has been made towards elucidating the physical and structural basis of this remarkable phenomenon. This paper focuses on the two hypotheses that drive current research into magnetoreception. One proposal reli... View full abstract»

• ### Saturation Curve for a Synthetic Antiferromagnetic System

Publication Year: 2009, Page(s):5266 - 5270
Cited by:  Papers (1)
| |PDF (376 KB) | HTML

For toggle magnetic random access memory, the saturation field represents the exterior limit of the work region. Exterior magnetic fields higher than the saturation field lead to an irremediable loss of the stored information because the antiferromagnetic state of the synthetic antiferromagnetic (SAF) structure becomes a ferromagnetic state and data stored in the magnetic memory cell are altered. ... View full abstract»

• ### Correlation Between the Degradation of Perpendicular Anisotropy and the Double Hysteresis Behavior in [Pd/Co]$_{rm n}$/FeMn Exchange Biased Thin Films

Publication Year: 2009, Page(s):5271 - 5276
Cited by:  Papers (2)
| |PDF (809 KB) | HTML

We clearly detected double hysteresis by increasing Co layer thickness and decreasing the number of bilayers in perpendicular exchange biased [Pd(0.6)/Co(t)] n/FeMn(11.6 nm) thin films. In-plane tensile stress calculations confirmed that the appearance of double hysteresis is closely related to the degradation of stress-induced perpendicular anisotropy in the [Pd/Co] multilayers.... View full abstract»

• ### Temperature Stability and Flux Losses Over Time in Sintered Nd–Fe–B Permanent Magnets

Publication Year: 2009, Page(s):5277 - 5280
Cited by:  Papers (13)
| |PDF (231 KB) | HTML

Demagnetization occurring with time in a constant temperature is often assumed to be negligible, provided that the operating point of the magnet is above the knee of the B-H curve. However, because it is important to ensure that no permanent flux losses occur in permanent magnets during their use in industrial applications, there is a clear need to quantify these time-dependent losses. We m... View full abstract»

• ### Effect of Factors on Coercivity in Sr–La–Co Sintered Ferrite Magnets

Publication Year: 2009, Page(s):5281 - 5288
Cited by:  Papers (12)
| |PDF (1662 KB) | HTML

We varied the composition and sintering temperature of Sr-La-Co ferrite magnets to analyze the effects of various important factors on coercivity (H cJ). We examined the effects of crystal grain size and distribution, the mechanism of magnetization reversal, the degree of crystal grain orientation (OD), and the anisotropy field (H A) on H cJ. W... View full abstract»

• ### Magnetometric Demagnetizing Factors for Various Shapes of Rotational Symmetry

Publication Year: 2009, Page(s):5289 - 5295
Cited by:  Papers (2)
| |PDF (399 KB) | HTML

We have investigated the magnetometric demagnetizing factors of rotation-symmetrical magnetic bodies of relative permeability mu placed in a uniform magnetic field parallel to the axis of rotation. The bodies we considered include a cylinder, a sphere, a bicone, and a rotating astroid. We numerically calculated the magnetometric demagnetizing factors from the surface magnetic charge densities sigm... View full abstract»

• ### Direct Current Effects on High-Frequency Properties of Patterned Permalloy Thin Films

Publication Year: 2009, Page(s):5296 - 5300
Cited by:  Papers (14)
| |PDF (506 KB) | HTML

We have investigated experimentally direct current (dc) effects on high-frequency properties of two different permalloy (Py) submicrometer patterns of 0.24 mum and 0.55 mum width, 10 mum length, and 100 nm thickness. The natural ferromagnetic resonance (FMR) frequencies for the two samples are about 8.5 and 11.5 GHz. A 50 mA dc produces a FMR frequency reduction of about 1 GHz in both samples. We ... View full abstract»

• ### B-Scalar Measurements by CMR-Based Sensors of Highly Inhomogeneous Transient Magnetic Fields

Publication Year: 2009, Page(s):5301 - 5306
Cited by:  Papers (15)
| |PDF (958 KB) | HTML

We present local measurements of absolute values of pulsed magnetic fields in a typical electromagnetic launching system-a small coilgun. For this purpose, we designed magnetic field sensors based on thin polycrystalline La0.83Sr0.17MnO3 films exhibiting a colossal magnetoresistance (CMR) effect. We measured the magnetic field distribution inside the bore of a coil... View full abstract»

• ### Demagnetization of Layered Ferromagnetic Structures for Magnetically Shielding: Frequency Considerations

Publication Year: 2009, Page(s):5307 - 5314
Cited by:  Papers (2)
| |PDF (453 KB) | HTML

This paper provides the background for evaluating the appropriate frequency from measured or manufacturer provided magnetic permeability data. The proper frequency is, among other parameters, a necessary prerequisite for the low residual field demagnetization required for several applications including biomagnetism and particle physics. The paper also presents an interpretation of the material-dep... View full abstract»

• ### Field-Circuit Hybrid Method for Magnetic Actuator Using a Laminate Composite

Publication Year: 2009, Page(s):5315 - 5318
| |PDF (295 KB) | HTML

The magnetic actuator using a laminate composite of piezoelectric (PZT) and magnetostrictive materials (MM) achieves active control of magnetic force without Joule heat loss. To study its characteristics, the field-circuit hybrid method is proposed based on the equivalent magnetic circuit and the finite element analysis (FEA) of piezoelectric and magnetic fields. The strain of laminate composite u... View full abstract»

• ### A New Structure for Permanent-Magnet-Biased Axial Hybrid Magnetic Bearings

Publication Year: 2009, Page(s):5319 - 5325
Cited by:  Papers (41)
| |PDF (509 KB) | HTML

We propose a new structure for a permanent-magnet-biased axial hybrid magnetic bearing. Starting with the inner air gap and the outer air gap of conventional axial magnetic bearings, we first construct a novel air gap between the permanent magnet and the outer housing, which we call the second air gap, separating the bias flux paths from the control flux paths. As a result, the control flux paths ... View full abstract»

• ### Optical Characterization of All-Magnetic NOT Gate Operation in Vortex Rings

Publication Year: 2009, Page(s):5326 - 5332
Cited by:  Papers (11)
| |PDF (1566 KB) | HTML

We have demonstrated deterministic operation of inverters (NOT gates) using vortex magnetization states in pairs of linked 5 mum diameter permalloy rings with a small region of overlap. The input ring is clipped so that the state can be controlled by global fields, and is designed to switch at lower fields than the unclipped output ring, which then inverts the logical state of the input. Optical c... View full abstract»

• ### Embedded Ring-Type Inductors Modeling With Application to Induction Heating Systems

Publication Year: 2009, Page(s):5333 - 5343
Cited by:  Papers (15)
| |PDF (1077 KB) | HTML

We derive integral expressions of the equivalent impedance of ring-type coils for induction heating systems. These expressions are obtained by integrating the analytical solution of the field generated by a circular filamentary current placed between two linear and homogeneous semi-infinite media. Constant current density is assumed for the coils, since they are wound with an appropriate Litz wire... View full abstract»

• ### Investigation of Fluid Structure Interaction of a Head Stack Assembly in a Hard Disk Drive

Publication Year: 2009, Page(s):5344 - 5351
Cited by:  Papers (7)
| |PDF (1871 KB) | HTML

An analysis of three-dimensional, unsteady flow field is conducted in a 3.5-in, 7200 rpm hard disk drive (HDD) using FLUENT software. The analysis is carried out for the head stack assembly (HSA) positioned at the outer diameter (OD). A finite element model (FEM) of the HSA, built in ANSYS, is used for the forced vibration analysis. The flow field analysis yields the aerodynamic forces and moments... View full abstract»

• ### Evaluating Track-Following Servo Performance of High-Density Hard Disk Drives Using Patterned Media

Publication Year: 2009, Page(s):5352 - 5359
Cited by:  Papers (6)  |  Patents (1)
| |PDF (1022 KB) | HTML

In recent years, track densities of magnetic hard disks have continued to grow. A promising approach to continuing the trend to ultrahigh density is using bit-patterned media (BPM). However, the implementation of BPM in hard disk drives (HDDs) to achieve high recording density is challenging and requires various new techniques, such as new servo pattern designs and position error signal (PES) deco... View full abstract»

• ### Validation of a Time-Harmonic Numerical Model for Solving Magnetic Field in End Region of a Radial-Flux Machine

Publication Year: 2009, Page(s):5360 - 5367
Cited by:  Papers (6)
| |PDF (764 KB) | HTML

We present an analysis of the magnetic field in the end region of a radial-flux rotating machine. In numerical simulations, we used three familiar boundary conditions to replace the modeling of the end shields and frame. We made measurements for comparison, and the simulation results were quite consistent with the measurements. Our analysis shows that the eddy current in the end shields and frame ... View full abstract»

• ### An Analytical Circuit Model of Switched Reluctance Motors

Publication Year: 2009, Page(s):5368 - 5375
Cited by:  Papers (18)
| |PDF (605 KB) | HTML

We have developed a dynamic analytical circuit model to simulate the performance of switched reluctance motors (SRMs). Our model expresses flux linkages as multiple decoupled one-argument functions, either current dependent or rotor position dependent, instead of one two-argument function dependent on both current and rotor position. We propose a novel approach for the computation of the air gap p... View full abstract»

• ### Measurement and Real-Time Modeling of Inductance and Flux Linkage in Switched Reluctance Motors

Publication Year: 2009, Page(s):5376 - 5382
Cited by:  Papers (19)  |  Patents (2)
| |PDF (1114 KB) | HTML

This paper presents a real-time model to identify the inductance and the flux linkage of switched reluctance motors (SRMs). A dynamic measurement method is used for the real-time modeling. An artificial neural network (ANN), designed in accordance with the inductance and the flux linkage data obtained from the dynamic measurement method, is used to make the real-time model. Experimental studies ar... View full abstract»

• ### In-Depth Study of the Torque Constant for Permanent-Magnet Machines

Publication Year: 2009, Page(s):5383 - 5387
Cited by:  Papers (11)
| |PDF (452 KB) | HTML

The torque constant, together with the back-EMF constant, was originally used in permanent-magnet DC commutator (PMDC) motors to couple electric circuit equations with mechanical equations. It is still an open question how these two constants should be defined in brushless DC (BLDC) motors and permanent-magnet (PM) AC motors. We present an in-depth study of these two constants, and conclude that t... View full abstract»

• ### Attenuation of Harmonic Rotor Vibration in a Cage Rotor Induction Machine by a Self-Bearing Force Actuator

Publication Year: 2009, Page(s):5388 - 5398
Cited by:  Papers (23)
| |PDF (1575 KB) | HTML

In this paper, attenuation of flexural rotor vibration in electrical machines is considered. In order to generate force on the machine rotor, an electromagnetic actuator based on self-bearing machine working principle is examined. A control method for attenuating harmonic rotor vibration components is applied in a 30 kW two-pole cage induction machine. The machine is equipped with a four-pole supp... View full abstract»

• ### Modeling of the Starting Performance of Large Solid-Pole Synchronous Motors Using Equivalent Circuit Approach

Publication Year: 2009, Page(s):5399 - 5404
Cited by:  Papers (5)
| |PDF (813 KB) | HTML

We present a method of modeling the starting performance of large solid pole synchronous motors based on an equivalent circuit approach. In this approach, the solid rotor body is assumed to have two sets of separate virtual windings. Therefore, the two-axis theory can be used for the solid pole synchronous motor. We derived parameters associated with the solid-pole, together with their transformat... View full abstract»

• ### Design, Prototyping, and Analysis of a Novel Tubular Permanent-Magnet Linear Machine

Publication Year: 2009, Page(s):5405 - 5413
Cited by:  Papers (19)
| |PDF (992 KB) | HTML

In this paper, we present a new tubular permanent-magnet linear machine with square-shaped cross section and derive its corresponding analytical model by solving Maxwell equations and applying the superposition theorem. The analytical field solution is necessary for obtaining an analytic form of the machine parameters and variables such as the self- and mutual inductances of the windings, the thru... View full abstract»

## Aims & Scope

IEEE Transactions on Magnetics is a peer-reviewed, archival journal in science and technology related to the basic physics and engineering of magnetism, magnetic materials, applied magnetics, magnetic devices, and magnetic data storage. The journal publishes scholarly articles of archival value as well as tutorial expositions and critical reviews of classical subjects and topics of current interest.

Full Aims & Scope

## Meet Our Editors

Editor-in-Chief
Pavel Kabos
National Institute of Standards and Technology