Major and minor stress-magnetization loops in textured polycrystalline Fe81.6Ga18.4 Galfenol

Abstract

Major and minor magnetization versus stress loops under different bias magnetic fields from 0.8 kA/m to 8.0 kA/m in 0.8 kA/m steps were measured in research grade, ⟨100⟩ oriented, textured polycrystalline Fe81.6Ga18.4. Both compressive and tensile stresses were applied from −63 MPa to 63 MPa for major loop analysis. Minor loops were generated by superimposing a 4.0 Hz, 2.8 MPa amplitude sinusoidal stress on different dc compressive stresses ranging from −40.7 MPa to −5.6 MPa in 7.0 MPa increments. Bias magnetic fields were applied in two ways, constant field in the sample obtained using a controller and constant current to the excitation coils. An energy-averaged model and related optimization method are presented to compare the experiments with simulations. The slope of magnetic flux density versus stress, i.e., the material's sensitivity to stress, is quantified from major and minor loop measurements. The peak sensitivity at constant field is about 75 T/GPa for constant-field major loops, whereas it is 41 T/GPa for constant-current major loops. The sensitivity for minor loops is consistently lower than for major loops, whether at constant field or constant current.

Efficient and robust nonlinear model for smart materials with application to composite magnetostrictive plates

“…In order to determine the geometry that maximizes the stiffness tunability of the composite, the Galfenol volume fraction and its offset from the horizontal midplane of the composite's cross section were varied. Surface plots of the normalized natural frequency were generated for each case; these plots are presented as a top view of the surface in figures 10, 11, 13, and 14. Results are presented for the model parameters given in table 2; the material properties for Galfenol were obtained through a [20].…”

“…To describe the full-scale Galfenol behavior, the 1D anhysteretic formulation of the efficient, fully coupled Evans-Dapino (ED) model [14,16] is used. This model has been successfully used to quantify the 3D nonlinear dynamic actuation of a Galfenol unimorph [17,18] and the major and minor stress-magnetization loops of a Galfenol rod [19,20].…”

Magnetostrictive vibration damper and energy harvester for rotating machinery

“…According to Table 1, µ G has a large variation with respect to applied stress, thus the magnetic field H G changes significantly during operation. Previous research 18,19 showed that the maximum magnetomechanical coupling is achieved when the magnetic field through the magnetostrictive materials is constant.…”

High Sensitivity Impact Force Sensor Based on Galfenol Alloy

“…Galfenol 合金的整体磁致伸缩是所有磁畴的磁 致伸缩的累积的结果，而磁畴的磁致伸缩取决于的 磁场强度与应力 [32] 。磁场作用下可使得磁畴向平行 于磁场方向旋转，应力作用下可使得磁畴向垂直于 负载方向旋转。对于 Galfenol 梁，偏置磁场需要使 [33] 拟合 Galfenol 梁冲击力传感器的试验 数据，得到输入冲击力与输出磁感应强度之间的函 数关系表达式为…”