scholarly journals Frequency Dependency of the Delta-E Effect and the Sensitivity of Delta-E Effect Magnetic Field Sensors

Sensors ◽  
2019 ◽  
Vol 19 (21) ◽  
pp. 4769 ◽  
Author(s):  
Spetzler ◽  
Golubeva ◽  
Müller ◽  
McCord ◽  
Faupel
Keyword(s):  
Magnetic Field ◽  
Resonance Frequency ◽  
Young’S Modulus ◽  
Ferromagnetic Resonance ◽  
Young's Modulus ◽  
Gilbert Damping ◽  
Simple Description ◽  
Frequency Dependency ◽  
Magnetic Sensitivity ◽  
Ferromagnetic Resonance Frequency

In recent years the delta-E effect has been used for detecting low frequency and low amplitude magnetic fields. Delta-E effect sensors utilize a forced mechanical resonator that is detuned by the delta-E effect upon application of a magnetic field. Typical frequencies of operation are from several kHz to the upper MHz regime. Different models have been used to describe the delta-E effect in those devices, but the frequency dependency has mainly been neglected. With this work we present a simple description of the delta-E effect as a function of the differential magnetic susceptibility χ of the magnetic material. We derive an analytical expression for χ that permits describing the frequency dependency of the delta-E effect of the Young’s modulus and the magnetic sensitivity. Calculations are compared with measurements on soft-magnetic (Fe90Co10)78Si12B10 thin films. We show that the frequency of operation can have a strong influence on the delta-E effect and the magnetic sensitivity of delta-E effect sensors. Overall, the delta-E effect reduces with increasing frequency and results in a stiffening of the Young’s modulus above the ferromagnetic resonance frequency. The details depend on the Gilbert damping. Whereas for large Gilbert damping the sensitivity continuously decreases with frequency, typical damping values result in an amplification close to the ferromagnetic resonance frequency.

SIMULATION OF NONLINEAR MAGNETORHEOLOGICAL PARTICLE-FILLED ELASTOMERS

2013 ◽  
Vol 02 (03n04) ◽  
pp. 1350018
Author(s):  
SHULEI SUN ◽  
XIONGQI PENG ◽  
ZAOYANG GUO
Keyword(s):  
Magnetic Field ◽  
Shear Modulus ◽  
Young’S Modulus ◽  
Applied Magnetic Field ◽  
Smart Materials ◽  
Young's Modulus ◽  
Particle Volume ◽  
Magnetorheological Elastomers ◽  
Maxwell Stress Tensor ◽  
Element Simulation

Polymer matrix filled with ferromagnetic particles is a class of smart materials whose mechanical properties can be changed under different magnetic field. They are usually referred to as magnetorheological elastomers (MREs). A finite element simulation was presented to describe the mechanical behavior of MREs with the nonlinearity of the particle magnetization being incorporated. By introducing the Maxwell stress tensor, a representative volume element (RVE) was proposed to calculate the Young's modulus and shear modulus of MREs due to the applied magnetic field. The influences of the applied magnetic field and the particle volume fractions in the shear modulus and Young's modulus were studied. Results show that the shear modulus increases with the magnitude of the applied magnetic field, while the Young's modulus decreases.

Large E-field tunability of magnetic anisotropy and ferromagnetic resonance frequency of co-sputtered Fe50Co50-B film

2015 ◽  
Vol 117 (17) ◽  
pp. 17D702 ◽  
Author(s):  
Shandong Li ◽  
Qian Xue ◽  
Honglei Du ◽  
Jie Xu ◽  
Qiang Li ◽  
...  
Keyword(s):  
Magnetic Anisotropy ◽  
Resonance Frequency ◽  
Ferromagnetic Resonance ◽  
Ferromagnetic Resonance Frequency

scholarly journals Magnetic Properties, Adhesion, and Nanomechanical Property of Co40Fe40W20 Films on Si (100) Substrate

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Wen-Jen Liu ◽  
Yung-Huang Chang ◽  
Sin-Liang Ou ◽  
Yuan-Tsung Chen ◽  
You-Cheng Liang ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Surface Energy ◽  
Resonance Frequency ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
High Surface ◽  
Contact Angles ◽  
Thickness Effect ◽  
High Coercivity ◽  
High Surface Energy

In this study, a Co40Fe40W20 alloy was sputtered onto Si (100) with thicknesses (tf) ranging from 18 to 90 nm, and the corresponding structure, magnetic properties, adhesive characteristics, and nanomechanical properties were investigated. X-ray diffraction (XRD) patterns of the Co40Fe40W20 films demonstrated a significant crystalline body-centered cubic (BCC) CoFe (110) structure when the thickness was 42 nm, and an amorphous status was shown when the thickness was 18 nm, 30 nm, 60 nm, and 90 nm. The saturation magnetization (Ms) showed a saturated trend as tf was increased. Moreover, the coercivity (Hc) showed a minimum 1.65 Oe with 30 nm. Hc was smaller than 4.5 Oe owing to the small grain size distribution and amorphous structure, indicating that the Co40Fe40W20 film had soft magnetism. The low-frequency alternating current magnetic susceptibility (χac) decreased as the frequency was increased. The χac revealed a thickness effect when greater thicknesses had a large χac. The maximum χac and optimal resonance frequency (fres) of Co40Fe40W20 were investigated. The maximum χac indicated the spin sensitivity and was maximized at the optimal resonance frequency. The 90 mm thickness had the highest χac 0.18 value at an fres of 50 Hz. The contact angles of the Co40Fe40W20 films are less than 90°, which indicated that the film had a good wetting effect and hydrophilicity. The surface energy was correlated with the adhesion and displayed a concave-down trend. CoFeW films can be used as a seed or buffer layer; therefore, the surface energy and adhesion are very important. The highest surface energy was 30.12 mJ/mm2 at 42 nm and demonstrated high adhesion. High surface energy has corresponding strong adhesive performance. The increased surface roughness can induce domain wall pinning effect and high surface energy, causing a high coercivity and strong adhesion. The increase of hardness and Young’s modulus could be reasonably inferred from the thinner CoFeW films. The hardness and Young’s modulus of CoFeW films are also displayed to saturated tendency when increasing thickness.

Sign in / Sign up

Export Citation Format

Share Document