High frequency characterization of Galfenol minor flux density loops

Ling Weng,Wenmei Huang,Ying Sun,Bowen Wang,Weina Li

doi:10.1063/1.4976579

Ling Weng, Wenmei Huang + Show 3 more

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https://doi.org/10.1063/1.4976579

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Abstract

This paper presents the first measurement of ring-shaped Galfenol’s high frequency-dependent minor flux density loops. The frequencies of applied AC magnetic field are 1k, 5k, 10k, 50k, 100k, 200k, 300k, 500 kHz. The measurements show that the cycle area between the flux density and magnetic field curves increase with increasing frequency. High frequency-dependent characterization, including coercivity, specific power loss, residual induction, and maximum relative permeability are discussed. Minor loops for different max induction are also measured and discussed at the same frequency 100 kHz. Minor loops with the same max induction 0.05 T for different frequencies 50, 100, 200, 300, 400 kHz are measured and specific power loss are discussed.

Highlights

Magnetostrictive materials show dimensional change in response to an external magnetic field, and they exhibit magnetization changes in response to an applied stress
Measurements of frequency-dependent minor flux density loops are shown in FIG.[2] for frequencies of 1k, 5k, 10k, 50k, 100k, 200k, 300k, 500 kHz
The cycle area is the area of hysteresis cycle, calculated as the integral

Summary

Introduction

Magnetostrictive materials show dimensional change in response to an external magnetic field, and they exhibit magnetization changes in response to an applied stress. Minor magnetization versus stress loops which are essential for Galfenol sensor design were measured in textured polycrystalline Fe81.6Ga18.4.5 Experimental data on Galfenol’s frequency-dependent response to dynamic stress with frequencies below 1 kHz were conducted by Scheidler.[6] Frequencydependence of dynamic piezomagnetic coefficient, Young’s modulus, and energy dissipation of solid and laminated Galfenol rods were measured for 2.88 MPa compressive stresses up to 1 kHz.[7] Hysteresis loops of strain versus magnetic field which were essential for Galfenol actuators at different frequencies from 1 Hz to 300 Hz were measured in a Fe83Ga17 Galfenol rod sample.[8] The hysteresis loops of different heat treated Fe81Ga19 ring-shaped samples were measured as a function of the frequencies from 0.25 Hz to 200 Hz and the coercivity was analyzed using different eddy-current-based models.[9] A key technical challenge is the limited experimental data on Galfenol’s minor flux density loops response to dynamic magnetic field of high frequency, which is critically important for the design of Galfenol patch transducer used for ultrasonic guided Lamb wave (GLW) inspection techniques.[10] In order to develop high frequency transducer based on magnetostrictive effect of Galfenol, it is necessary to determine the high frequency characterization of Galfenol flux density loops

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Conclusion