Scheduled System Maintenance:
On May 6th, system maintenance will take place from 8:00 AM - 12:00 PM ET (12:00 - 16:00 UTC). During this time, there may be intermittent impact on performance. We apologize for the inconvenience.
By Topic

Magnetics, IEEE Transactions on

Issue 3 • Date May 1984

Filter Results

Displaying Results 1 - 10 of 10
  • [Front cover and table of contents]

    Publication Year: 1984 , Page(s): 0
    Save to Project icon | Request Permissions | PDF file iconPDF (226 KB)  
    Freely Available from IEEE
  • A theoretical and experimental comparison of the longitudinal and vertical modes of magnetic recording

    Publication Year: 1984 , Page(s): 461 - 467
    Cited by:  Papers (14)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (880 KB)  

    The similarities and differences between longitudinally and vertically oriented thin metallic film recording media are discussed theoretically and experimentally. It is argued that, even though the writing process is not perfectly understood, the two modes of recording are essentially equivalent. On the basis of published experimental data, it is shown that negligible differences in performance occur, in accord with simple theoretical expectations. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Geometric effects in the magnetic recording process

    Publication Year: 1984 , Page(s): 468 - 478
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1216 KB)  

    A simplified view of magnetic recording is presented in which the effect of head-medium geometry is clearly exhibited. The model is applied to contact recording with a ring head on thick particulate media. Demagnetization fields are neglected and identical particles with angularly invariant switching fields are considered with various orientation distributions in the recording plane. For all orientation distributions symmetric about the longitudinal direction the longitudinal magnetization component vanishes at the head surface and increases with depth into the medium. Conversely, the vertical component is maximum at the head surface and decreases with depth. The resulting recording spectra therefore have greater magnitudes for vertically well-oriented particles and isotropic distributions of particles with biaxial symmetry. At short wavelengths these distributions give approximately 5 dB more output than longitudinally well-oriented media. The depth variation of longitudinal magnetization also provides one explanation for the peak in the short wavelength input-output curve measured on longitudinal media. These conclusions are expected to be dependent on the assumed angular variation of the particle nucleation field. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Measurements and self-consistent calculations of the magnetic fields near a perpendicular medium

    Publication Year: 1984 , Page(s): 479 - 485
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (640 KB)  

    Several models used to describe magnetic fields from perpendicular media and heads have been evaluated with the high-resolution field measurement system. Perpendicular fringing fields near statically written magnetization patterns were computed using an iterative self-consistent technique utilizing a hyperbolic-tangent and a Stoner-Wohlfarth hysteresis model. The fields predicted by both theories were compared with those measured from magnetization patterns statically written in two different Co-Cr media with a ring head and a single-pole head where the media had either been presaturated or demagnetized. The field distributions predicted by both theories were in generally good agreement with the measurements; the theoretical amplitudes were within 20 percent for the hyperbolic-tangent model, but significantly larger amplitude errors were found for the Stoner-Wohlfarth model. Write fields were measured from a ring head and a single-pole head, and a theory for each of the heads was shown to be in excellent agreement with the measurements. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Patterning effect on easy axis alignment in permalloy thin film

    Publication Year: 1984 , Page(s): 485 - 488
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (448 KB)  

    An investigation has been made of the domain configuration in photofabricated Permalloy patterns. In some cases the direction of the easy axis is found to be rotated perpendicular to that initially induced. This change can be explained in terms of uniaxial tension simulated by a two-dimensional finite-element method. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comparison of sensitivity functions for ideal probe and ring-type heads

    Publication Year: 1984 , Page(s): 488 - 494
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (616 KB)  

    Analytical models of ideal infinitesimally thin probe-type heads have been presented and compared with a model of an ideal ring-type head. It is shown that with respect to readback resolution the characteristics of probe models are inferior to those of the ring model. It is also shown that resolution of the probe model is reduced further if media with a soft magnetic underlayer is used. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Crystallographic and magnetic investigation on W-type-hexaferrite single crystals in the solid solution series SrZn2-xCoxFe16O27

    Publication Year: 1984 , Page(s): 495 - 500
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (624 KB)  

    The saturation magnetization and the magnetocrystalline anisotropy were measured on single crystals in the solid solution series SrZn2-xCoxFe16O27(SrZn2-xCox-W) at 298 K and 6 K. Lattice constants and Curie-temperatures are also given as a function of the composition. The magnetocrystalline anisotropy changes from uniaxial to planar dependent on temperature and cobalt substitution at x \approx 0.5 for 6 K and x \approx 0.85 for 298 K. The six-fold anisotropy in the basal plane of the planar W-hexaferrites increases strongly with increasing cobalt content. Crystals with a low Co substitution (x = 0.33 and 0.67) have an anomalous discontinuity in their hard direction magnetization curves; indicating a first-order magnetization process. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An alternative numerical approach for computing eddy currents: Case of the double-layered plate

    Publication Year: 1984 , Page(s): 500 - 506
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (608 KB)  

    A numerical approach is presented for cases where induced eddy current densities are to be computed in axisymmetric situations. Conductors are represented as stacks of inductively coupled, concentric, metal rings in which current is excited by an external coil. Matrix techniques are used to solve the resulting set of circuit equations. Sinusoidally induced currents in a sandwich plate consisting of two layers of different metals are discussed as an application. Comparison is made with a finite element calculation and with results obtained via an analytical approach. Nonsinusoidal excitation is also briefly discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • [Back cover]

    Publication Year: 1984 , Page(s): 0
    Save to Project icon | Request Permissions | PDF file iconPDF (929 KB)  
    Freely Available from IEEE
  • Design of polyphase motors with PM excitation

    Publication Year: 1984 , Page(s): 507 - 515
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (792 KB)  

    Design guidelines are presented for synchronous motors with permanent magnet (PM) excitation. A general model is established and the dependence of the electric and magnetic loadings on the angle between the armature and field excitations is put in evidence. For this angle there exists an optimal value which yields maximum torque for maximum allowable flux density in the teeth. Another value yields the minimum volume for the permanent magnets. These values guide the selection of the operating point of the motor and its preliminary design. It is found that, when the pole pitch exceeds a certain value, the magnet requires more space than a current carrying winding. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

IEEE Transactions on Magnetics publishes research in science and technology related to the basic physics and engineering of magnetism, magnetic materials, applied magnetics, magnetic devices, and magnetic data storage.

Full Aims & Scope

Meet Our Editors

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