Measurement of Dielectric and Magnetic Properties of Ferromagnetic Materials at Microwave Frequencies

1957 ◽  
Vol 36 (2) ◽  
pp. 427-448 ◽  
Author(s):  
Wilhelm Von Aulock ◽  
John H. Rowen
Keyword(s):  
Magnetic Properties ◽  
Ferromagnetic Materials ◽  
Microwave Frequencies

scholarly journals Novel MNZ-type microwave sensor for testing magnetodielectric materials

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Abhishek Kumar Jha ◽  
Nicolò Delmonte ◽  
Adam Lamecki ◽  
Michal Mrozowski ◽  
Maurizio Bozzi
Keyword(s):  
Magnetic Properties ◽  
Relative Permittivity ◽  
Microstrip Line ◽  
Dielectric Materials ◽  
Metal Strip ◽  
Network Analyzer ◽  
Microwave Frequencies ◽  
Microwave Sensor ◽  
Iron Garnet ◽  
Good Agreement

Abstract A novel microwave sensor with the mu-near-zero (MNZ) property is proposed for testing magnetodielectric material at 4.5 GHz. The sensor has a double-layer design consisting of a microstrip line and a metal strip with vias on layers 1 and 2, respectively. The proposed sensor can detect a unit change in relative permittivity and relative permeability with a difference in the operating frequency of 45 MHz and 78 MHz, respectively. The MNZ sensor is fabricated and assembled on two layers of Taconic RF-35 substrate, with thicknesses of 0.51 mm and 1.52 mm, respectively, for the measurement of the sample under test using a vector network analyzer. The dielectric and magnetic properties of two standard dielectric materials (Taconic CER-10 and Rogers TMM13i) and of yttrium–gadolinium iron garnet are measured at microwave frequencies. The results are found to be in good agreement with the values available in the literature, which shows the applicability of the prototype for sensing of magnetodielectric materials.

scholarly journals Measuring And Computing System for Studying the Magnetic Characteristics of Soft Magnetic Materials

2021 ◽  
pp. 21-26
Author(s):  
A.V. Egorov ◽  
V.V. Polyakov ◽  
A.A. Lependin ◽  
D.D. Ruder
Keyword(s):  
Magnetic Properties ◽  
Eddy Current ◽  
Magnetic Permeability ◽  
Computing System ◽  
Ferromagnetic Materials ◽  
Soft Magnetic Materials ◽  
Magnetic Characteristics ◽  
Soft Magnetic ◽  
Non Destructive

Non-destructive eddy current diagnostics of the structure, composition, physical and mechanical properties of ferromagnetic materials, as well as eddy current monitoring of the operational parameters of products manufactured from them, requires knowledge of the magnetic characteristics of these materials. In eddy current measurements, the results obtained are influenced by a significant number of factors — magnetic and electrical properties of materials, geometric characteristics of products, measurement conditions, design features of an eddy current sensor, etc. Also, the magnetic properties themselves have high structural sensitivity. Thus, identification of the diagnosed parameters puts great importance on the tasks to separate the influencing factors and isolate the contribution of the magnetic properties. This paper describes the measuring and computing system that allows automatic determination of the magnetic permeability of soft magnetic ferromagnetic materials at various values of the strength of the external magnetizing field. The system has been tested using soft magnetic ferrites samples. An experimental dependence of the magnetic permeability on the magnitude of the magnetic field for the initial section of the main magnetization curve is presented. The obtained initial magnetic permeability is compared with the data of independent indirect measurements. The proposed system provides an increase in the reliability and accuracy of the results of the experimental determination of magnetic characteristics and can be used for non-destructive diagnostics of products made of soft magnetic ferromagnetic materials.

The magnetic properties of the ferromagnetic materials used for HTS transformers at 77 K

2003 ◽  
Vol 13 (2) ◽  
pp. 2313-2316 ◽  
Author(s):  
Min Chen ◽  
Y.J. Yu ◽  
L.Y. Xiao ◽  
Q.L. Wang ◽  
Wooho Chung ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Ferromagnetic Materials ◽  
Materials Used

scholarly journals Ferromagnetically filled carbon nano-onions: the key role of sulfur in dimensional, structural and electric control

2018 ◽  
Vol 5 (1) ◽  
pp. 170981 ◽  
Author(s):  
D. Medranda ◽  
J. Borowiec ◽  
Xiao Zhang ◽  
S. Wang ◽  
K. Yan ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Chemical Vapour Deposition ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Ferromagnetic Materials ◽  
Electric Properties ◽  
Suitable Method ◽  
Electric Control ◽  
Different Types

A key challenge in the fabrication of ferromagnetically filled carbon nano-onions (CNOs) is the control of their thickness, dimensions and electric properties. Up to now literature works have mainly focused on the encapsulation of different types of ferromagnetic materials including α-Fe, Fe 3 C, Co, FeCo, FePd 3 and others within CNOs. However, no report has yet shown a suitable method for controlling both the number of shells, diameter and electric properties of the produced CNOs. Here, we demonstrate an advanced chemical vapour deposition approach in which the use of small quantities of sulfur during the pyrolysis of ferrocene allows for the control of (i) the diameter of the CNOs, (ii) the number of shells and (iii) the electric properties. We demonstrate the morphological, structural, electric and magnetic properties of these new types of CNOs by using SEM, XRD, TEM, HRTEM, EIS and VSM techniques.

scholarly journals Homogenization of Chiral Magnetic Materials: A Mathematical Evidence of Dzyaloshinskii’s Predictions on Helical Structures

2020 ◽  
Vol 30 (3) ◽  
pp. 1229-1262 ◽  
Author(s):  
E. Davoli ◽  
G. Di Fratta
Keyword(s):  
Magnetic Properties ◽  
Magnetic Materials ◽  
Energy Functional ◽  
Ferromagnetic Materials ◽  
Helical Structures ◽  
Magnetic Composites ◽  
Spin Lattice ◽  
Spin Interactions ◽  
Moriya Interaction ◽  
Effective Description

AbstractIn this paper, we investigate the influence of the bulk Dzyaloshinskii–Moriya interaction on the magnetic properties of composite ferromagnetic materials with highly oscillating heterogeneities, in the framework of $$\Gamma $$Γ-convergence and 2-scale convergence. The homogeneous energy functional resulting from our analysis provides an effective description of most of the magnetic composites of interest nowadays. Although our study covers more general scenarios than the micromagnetic one, it builds on the phenomenological considerations of Dzyaloshinskii on the existence of helicoidal textures, as a result of possible instabilities of ferromagnetic structures under small relativistic spin–lattice or spin–spin interactions. In particular, we provide the first quantitative counterpart to Dzyaloshinskii’s predictions on helical structures.

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