Flexible Pr‐Doped Fe–Ga Composite Materials: Preparation, Microstructure, and Magnetostrictive Properties

Abstract

Herein, the manufacture process and the results of investigations into the microstructure and magnetic properties of flexible Fe83Ga17Prx (x = 0, 0.2, 1.0) composite materials are presented. The Fe83Ga17Prx (x = 0, 0.2, 1.0) alloy powders with particle size of 75 μm and epoxy binder are bonded at a weight ratio of 2:1, and then orient under a constant applied magnetic field of 10 kOe and airdry 12 h, finally processed into composite material. The microstructure and magnetic properties of as‐cast alloy, unoriented (UN), and oriented (OR) composite materials are examined by X‐ray diffractometer (XRD), scanning electron microscopy and energy dispersive spectrometry (SEM/EDS), vibrating sample magnetometer (VSM), and strain gauge method. The results show that the Pr‐doped Fe–Ga as‐cast samples consist of A2 matrix phase and rare‐earth‐rich phase. As the Pr content increases, the grain sizes of A2 matrix phase decrease. The OR composite materials show significant magnetic anisotropy. Compared with as‐cast and UN composite materials, the magnetostriction of OR composite materials increase. The highest value of magnetostriction (310 ppm) is obtained in the flexible Fe83Ga17Pr1.0 composite material.

Prospects of Using Fe-Ga Alloys for Magnetostrictive Applications at High Frequencies

“…In recent years, it has been shown that the replacement of the binary Fe-Ga by the ternary FeGaRE alloy with a low RE content (up to 3 at. %) in magnetostrictive composites allows for the achievement of a significant increase in magnetostriction [93,94]. Moreover, based on the data [36], it can be assumed that this can also improve frequency stability and reduce core loss at higher reversal frequencies.…”

“…In the example of magnetostrictive composites based on Terfenol-D, the effectiveness of this approach was shown [95]. In the case of Fe-Ga, this also leads to a significant increase in magnetostriction, in some cases more than three times compared to un-oriented samples [87,93]. This effect is highly dependent on the morphology and particle size, as well as the alloy-epoxy ratio and solidification conditions, as well as the magnitude of the applied magnetic field.…”