The Experts below are selected from a list of 132 Experts worldwide ranked by ideXlab platform

A Zhukov - One of the best experts on this subject based on the ideXlab platform.

  • domain walls collision in fe rich and co rich glass covered microwires
    EPJ Web of Conferences, 2013
    Co-Authors: A Chizhik, J Gonzalez, J M Blanco, M Ipatov, V Zhukova, A Zhukov
    Abstract:

    We report the results of the investigation of domain walls propagation in Fe-rich and Co-rich microwires performed using Sixtus-Tonks and magneto-optical Kerr effect techniques. It was found that under certain experimental conditions we are able to create the regime of the motion of two domain walls moving to opposite directions which terminates by the collision of the domain walls. Also the domain walls collision was visualized using magneto-optical Kerr effect microscope when the surface giant Barkhausen Jump induced by circular magnetic field has been observed.

  • magneto optical study of domain wall dynamics and giant Barkhausen Jump in magnetic microwires
    Journal of Magnetism and Magnetic Materials, 2012
    Co-Authors: A Chizhik, J M Blanco, A Zhukov, J Gonzalez
    Abstract:

    Investigation of surface domain walls motion in Co-rich magnetic microwires has been performed in circular and axial magnetic fields. The dc axial magnetic field acceleration of the domain wall motion related to the influence of the axial field on the structure of the moving domain wall has been discovered. Pulsed axial magnetic field induced unidirectional motion of surface domain wall also has been found.

  • temperature dependence of the switching field and its distribution function in fe based bistable microwires
    Applied Physics Letters, 2003
    Co-Authors: R Varga, M Vazquez, A Zhukov, K Garcia, P Vojtanik
    Abstract:

    The switching field distribution for magnetization reversal in a single Barkhausen Jump of a bistable Fe-based amorphous microwire as well as its temperature dependence have been investigated in the temperature range from 77 to 450 K. Two processes have been identified to be responsible for the temperature dependence of the switching field: magnetostrictive volume domain wall pinning on stresses and relaxation effects due to local structural rearrangements. While at low temperatures, pinning on the atomic level defects plays the dominant role, magnetostrictive pinning becomes more important at intermediate temperatures. A simple model is proposed considering both energy contributions that fits reasonably well with experimental data and allows us to interpret additionally the observed temperature dependence of the switching field fluctuations.

  • the remagnetization process in thin and ultra thin fe rich amorphous wires
    Journal of Magnetism and Magnetic Materials, 1995
    Co-Authors: A Zhukov, M Vazquez, J J Velazquez, Horia Chiriac, V Larin
    Abstract:

    A comparative study of the remagnetization process of highly-magnetostrictive as-cast Fe-rich amorphous wires having different diameters (from 165 to 10 μm) and lengths (between 10 cm and 2 mm) is here reported for the first time. Wires obtained by conventional in-rotating-water quenching (165 down to 70 μm diameter) and by a modified Taylor's technique (2.5 μm glass cover on 10 to 15 μm diameter magnetic core) are studied. Macroscopic and local hysteresis loops are measured by induction technique with the help of large and very tiny pick up coils respectively. From the latter, the magnetization profile of these magnetically bistable wires is determined. The critical length to observe a single and large Barkhausen Jump when remagnetizing decreases with the diameter of the sample. In particular, for the wires covered by glass the critical length to observe spontaneous bistability is less than 2 mm. Values of those critical lengths are interpreted taking into account the compromise between magnetostatic and magnetoelastic energy terms.

J Gonzalez - One of the best experts on this subject based on the ideXlab platform.

  • domain walls collision in fe rich and co rich glass covered microwires
    EPJ Web of Conferences, 2013
    Co-Authors: A Chizhik, J Gonzalez, J M Blanco, M Ipatov, V Zhukova, A Zhukov
    Abstract:

    We report the results of the investigation of domain walls propagation in Fe-rich and Co-rich microwires performed using Sixtus-Tonks and magneto-optical Kerr effect techniques. It was found that under certain experimental conditions we are able to create the regime of the motion of two domain walls moving to opposite directions which terminates by the collision of the domain walls. Also the domain walls collision was visualized using magneto-optical Kerr effect microscope when the surface giant Barkhausen Jump induced by circular magnetic field has been observed.

  • magneto optical study of domain wall dynamics and giant Barkhausen Jump in magnetic microwires
    Journal of Magnetism and Magnetic Materials, 2012
    Co-Authors: A Chizhik, J M Blanco, A Zhukov, J Gonzalez
    Abstract:

    Investigation of surface domain walls motion in Co-rich magnetic microwires has been performed in circular and axial magnetic fields. The dc axial magnetic field acceleration of the domain wall motion related to the influence of the axial field on the structure of the moving domain wall has been discovered. Pulsed axial magnetic field induced unidirectional motion of surface domain wall also has been found.

  • Barkhausen Jump distributions in a micromagnetic model
    Journal of Magnetism and Magnetic Materials, 1998
    Co-Authors: O A Chubykalo, J M Gonzalez, J Gonzalez
    Abstract:

    Abstract We examine and qualify the collective behavior of a micromagnetic model, which allowed us to distinguish between local events (avalanches) and global ones (Barkhausen Jumps). We show that it is possible to scale, in limited system size ranges, the Barkhausen Jump distribution functions and discuss the applicability to the description of the collective behavior of the self-organized criticality ideas.

Juan Chen - One of the best experts on this subject based on the ideXlab platform.

  • the effect of temperature on the average volume of Barkhausen Jump on q235 carbon steel
    Journal of Magnetism and Magnetic Materials, 2016
    Co-Authors: Lei Guo, Di Shu, Liang Yin, Juan Chen
    Abstract:

    Abstract On the basis of the average volume of Barkhausen Jump (AVBJ) v ¯ generated by irreversible displacement of magnetic domain wall under the effect of the incentive magnetic field on ferromagnetic materials, the functional relationship between saturation magnetization M s and temperature T is employed in this paper to deduce the explicit mathematical expression among AVBJ v ¯ , stress σ , incentive magnetic field H and temperature T . Then the change law between AVBJ v ¯ and temperature T is researched according to the mathematical expression. Moreover, the tensile and compressive stress experiments are carried out on Q235 carbon steel specimens at different temperature to verify our theories. This paper offers a series of theoretical bases to solve the temperature compensation problem of Barkhausen testing method.

  • the effect of stress and incentive magnetic field on the average volume of magnetic Barkhausen Jump in iron
    Journal of Magnetism and Magnetic Materials, 2015
    Co-Authors: Di Shu, Lei Guo, Liang Yin, Zhaoyang Chen, Juan Chen
    Abstract:

    Abstract The average volume of magnetic Barkhausen Jump (AVMBJ) v ¯ generated by magnetic domain wall irreversible displacement under the effect of the incentive magnetic field H for ferromagnetic materials and the relationship between irreversible magnetic susceptibility χirr and stress σ are adopted in this paper to study the theoretical relationship among AVMBJ v ¯ (magneto-elasticity noise) and the incentive magnetic field H. Then the numerical relationship among AVMBJ v ¯ , stress σ and the incentive magnetic field H is deduced. Utilizing this numerical relationship, the displacement process of magnetic domain wall for single crystal is analyzed and the effect of the incentive magnetic field H and the stress σ on the AVMBJ v ¯ (magneto-elasticity noise) is explained from experimental and theoretical perspectives. The saturation velocity of Barkhausen Jump characteristic value curve is different when tensile or compressive stress is applied on ferromagnetic materials, because the resistance of magnetic domain wall displacement is different. The idea of critical magnetic field in the process of magnetic domain wall displacement is introduced in this paper, which solves the supersaturated calibration problem of A V M B J - σ calibration curve.

M Vazquez - One of the best experts on this subject based on the ideXlab platform.

  • double large Barkhausen Jump in soft soft composite microwires
    Journal of Physics D, 2010
    Co-Authors: G Infante, G A Badiniconfalonieri, R P Del Real, M Vazquez
    Abstract:

    The magnetic properties of double layer microwires consisting of a soft FeSiBP amorphous core, an intermediate non-magnetic glass spacer and a softer FeNi outer shell have been investigated. As in the case of other magnetostatically coupled two-phase systems, the hysteresis loops are characterized by two well-defined Barkhausen Jumps corresponding each to the magnetization reversal of the individual phases, separated by a plateau. The strong dipolar interaction that leads to the appearance of the plateau is investigated in terms of the microwire geometry. It is shown that this source of coupling is capable of increasing up to one order of magnitude the switching field of the Fe-rich core. Thus, magnetic bistability can be effectively controlled in these kinds of composite wires.

  • temperature dependence of the switching field and its distribution function in fe based bistable microwires
    Applied Physics Letters, 2003
    Co-Authors: R Varga, M Vazquez, A Zhukov, K Garcia, P Vojtanik
    Abstract:

    The switching field distribution for magnetization reversal in a single Barkhausen Jump of a bistable Fe-based amorphous microwire as well as its temperature dependence have been investigated in the temperature range from 77 to 450 K. Two processes have been identified to be responsible for the temperature dependence of the switching field: magnetostrictive volume domain wall pinning on stresses and relaxation effects due to local structural rearrangements. While at low temperatures, pinning on the atomic level defects plays the dominant role, magnetostrictive pinning becomes more important at intermediate temperatures. A simple model is proposed considering both energy contributions that fits reasonably well with experimental data and allows us to interpret additionally the observed temperature dependence of the switching field fluctuations.

  • the remagnetization process in thin and ultra thin fe rich amorphous wires
    Journal of Magnetism and Magnetic Materials, 1995
    Co-Authors: A Zhukov, M Vazquez, J J Velazquez, Horia Chiriac, V Larin
    Abstract:

    A comparative study of the remagnetization process of highly-magnetostrictive as-cast Fe-rich amorphous wires having different diameters (from 165 to 10 μm) and lengths (between 10 cm and 2 mm) is here reported for the first time. Wires obtained by conventional in-rotating-water quenching (165 down to 70 μm diameter) and by a modified Taylor's technique (2.5 μm glass cover on 10 to 15 μm diameter magnetic core) are studied. Macroscopic and local hysteresis loops are measured by induction technique with the help of large and very tiny pick up coils respectively. From the latter, the magnetization profile of these magnetically bistable wires is determined. The critical length to observe a single and large Barkhausen Jump when remagnetizing decreases with the diameter of the sample. In particular, for the wires covered by glass the critical length to observe spontaneous bistability is less than 2 mm. Values of those critical lengths are interpreted taking into account the compromise between magnetostatic and magnetoelastic energy terms.

  • the magnetization reversal process in amorphous wires
    IEEE Transactions on Magnetics, 1995
    Co-Authors: M Vazquez, D X Chen
    Abstract:

    The most outstanding property of amorphous wires is their capability to magnetized through a single Barkhausen Jump giving rise to squared hysteresis loop. This phenomenon is spontaneously shown in large magnetostriction wires in the as-quenched state. According to the previous model, such a Barkhausen Jump arises from the magnetization reversal inside core having axial easy magnetization axis. In this work, we review some recent results leading to a refinement of the previous model paying particular attention to the domain structure close to wires having different lengths. The existence of "closure" domains in such regions and the ends of existence of their variation when applied fields up to a critical value for magnetization reversal process. To deepen the knowledge of the dynamics of the wall responsible for the magnetization two experimental studies were performed namely, the conventional Sixtus-Tonks experiment and the magnetization reversal under homogeneous applied field along the sample. The main conclusions are: (a) the reversal process is spontaneously initiated close to the end of the wire where the wall is depinned and propagates along the entire wire, (b) the starting end alternates in each reversal or remains the same depending on an additional external applied field, and (c) the wall during the reversal approaches a planar shape. >

A Chizhik - One of the best experts on this subject based on the ideXlab platform.

  • domain walls collision in fe rich and co rich glass covered microwires
    EPJ Web of Conferences, 2013
    Co-Authors: A Chizhik, J Gonzalez, J M Blanco, M Ipatov, V Zhukova, A Zhukov
    Abstract:

    We report the results of the investigation of domain walls propagation in Fe-rich and Co-rich microwires performed using Sixtus-Tonks and magneto-optical Kerr effect techniques. It was found that under certain experimental conditions we are able to create the regime of the motion of two domain walls moving to opposite directions which terminates by the collision of the domain walls. Also the domain walls collision was visualized using magneto-optical Kerr effect microscope when the surface giant Barkhausen Jump induced by circular magnetic field has been observed.

  • magneto optical study of domain wall dynamics and giant Barkhausen Jump in magnetic microwires
    Journal of Magnetism and Magnetic Materials, 2012
    Co-Authors: A Chizhik, J M Blanco, A Zhukov, J Gonzalez
    Abstract:

    Investigation of surface domain walls motion in Co-rich magnetic microwires has been performed in circular and axial magnetic fields. The dc axial magnetic field acceleration of the domain wall motion related to the influence of the axial field on the structure of the moving domain wall has been discovered. Pulsed axial magnetic field induced unidirectional motion of surface domain wall also has been found.

  • influence of external tensile stress on the stray field of bistable fe rich wires
    Physica Status Solidi (a), 2009
    Co-Authors: P Gawronski, A Chizhik, Julian Gonzalez
    Abstract:

    We consider an influence of the external tensile stress on the magnetostatic interaction between two wires. Measured magnetization profiles serve as a basis to calculate the spatial distribution of the stray field and to evaluate the wire-wire interaction. Numerical calculations reproduce the experimentally observed asymmetry of the shift of the switching field at the first and the second Barkhausen Jump of the hysteresis loop. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)