Abstract
Inductance spectroscopy is a particular formulation variant of the well known complex impedance formalism typically used for the electric characterization of dielectric, ferroelectric, and piezoelectric materials. It has been successfully exploited as a versatile tool for characterization of the magnetization dynamics in amorphous ribbons and wires by means of simple experiments involving coils for sample holding and impedance analyzer equipment. This technique affords the resolution of the magnetization processes in soft magnetic materials, in terms of reversible deformation of pinned domain walls, domain wall displacements and spin rotation, for which characteristic parameters such as the alloy initial permeability and the relaxation frequencies, indicating the dispersion of each process, can be defined. Additionally, these parameters can be correlated with chemical composition variation, size effects and induced anisotropies, leading to a more physical insight for the understanding of the frequency dependent magnetic response of amorphous alloys, which is of prime interest for the development of novel applications in the field of telecommunication and sensing technologies. In this work, a brief overview, together with recent progress on the magnetization dynamics of amorphous ribbons, wires, microwires and biphase wires, is presented and discussed for the intermediate frequency interval between 10 Hz and 13 MHz.
Highlights
Amorphous alloys obtained from rapid solidification techniques as thin ribbons and fine wires have been the subject of research since the 1980s due to their ultrasoft magnetic character which has allowed interesting technological applications in devices for conversion of electromagnetic energy into mechanic energy and for signal processing; power electronics, electric power conditioning, magnetic sensors, telecommunication, automotive magnetics; and electronic article surveillance [1,2]
These curves afford the resolution of the active magnetization mechanisms across the frequency range for a given hac intensity 22,23
Inductance spectroscopy has been employed as a powerful tool for characterization of the magnetization dynamics in amorphous ribbons and wires, by means of the resolution of the magnetization mechanism within the materials, in terms of reversible deformation of pinned domain walls, domain wall displacements and spin rotation, for which characteristic parameters, such as the alloy initial permeability and the relaxation frequencies, indicating the dispersion of each process, can be established
Summary
Amorphous alloys obtained from rapid solidification techniques as thin ribbons (with characteristic thickness below 30 microns and variable lengths) and fine wires (with typical diameters lower than 120 microns and variable lengths) have been the subject of research since the 1980s due to their ultrasoft magnetic character which has allowed interesting technological applications in devices for conversion of electromagnetic energy into mechanic energy and for signal processing; power electronics, electric power conditioning, magnetic sensors, telecommunication, automotive magnetics; and electronic article surveillance [1,2]. For amorphous glass covered microwires, there are two kinds of stress sources (a) axial stress due to the cooling process and (b) radial stress caused by the difference in thermal expansion coefficients between the metallic nucleus and the glass coating [17,18] These internal stress variations follow a rather complex distribution with axial, circular and radial components changing rapidly from positive (at the axial zone) to negative (at the surrounding shell) including maximum values at half the radius, as well as on the wire edges, and even zero stress value is expected at the precise microwire centre [19,20]. Recent progress on the magnetization dynamics, in terms of the resolution of magnetization processes as a function of frequency, for amorphous ribbons and wires, is presented and discussed
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
