Giant enhancement in the magnetostrictive effect of FeGa alloys doped with low levels of terbium

Abstract

We present the effects of terbium additives upon the microstructure and magnetic properties of Fe83Ga17Tbx alloys (x = 0, 0.2, 0.4, 0.6, and 0.8), prepared by vacuum electric arc-melting and directional solidification techniques. Experiments indicate that small amounts of terbium more than double the saturation magnetostriction of a [110] textured Fe83Ga17 alloy with λ = 72 × 10−6 and lower the magnetostriction saturation field. The pronounced increase in magnetostriction stems from the appearance of [100] texture in polycrystalline alloys. It is verified that [110] and [100] textures are enhanced by the introduction of terbium atoms preferentially residing in a Tb-rich intergranular phase.

Tb solid solution and enhanced magnetostriction in Fe83Ga17 alloys

“…Focusing on Tb-doped Fe-Ga alloys, Jiang et al reported the increase of magnetostriction from 72 ppm to 160 ppm in the directionally solidified Fe 83 Ga 17 Tb x (x = 0.2) polycrystalline alloys [9]. The increase of the magnetostriction was attributed to the formation of preferential orientation enhanced by the precipitation of Tb-rich phase [9].…”

“…The increase of the magnetostriction was attributed to the formation of preferential orientation enhanced by the precipitation of Tb-rich phase [9]. Further, in the [110]-textured Fe 81 Ga 19 Tb x (x = 0.3) polycrystalline alloy, Fitchorov et al found that Tb doping resulted in an increase in magnetization, a reduction of saturation field and a decrease in magnitude of the temperature coefficient of the mangetostriction [12].…”

“…With relatively high magnetostriction, low coercivity and good ductility, Fe-Ga alloy is a promising magnetostrictive material for magnetic actuators and sensors [5][6][7][8][9][10][11][12].…”

Influences of rare earth element Ce-doping and melt-spinning on microstructure and magnetostriction of Fe83Ga17 alloy

“…Tb doping resulted in an increase in magnetization, a reduction of saturation field, as well as a decrease in magnitude of the magnetostriction temperature coefficient. Similarly, L.P. Jiang et al [15] indicated that the low-level doping of terbium can enhance the magnetostrictive coefficient of Fe-Ga alloy at room temperature. Moreover, L.P. Jiang et al [16] studied the microstructure and magnetostriction of Fe 83 Ga 17 Dy x (x=0, 0.2, 0.4, 0.6) alloys.…”

Textured, dense and giant magnetostrictive alloy from fissile polycrystal

“…Another important application of orientation is in the magnetostrictive materials, which have drawn ever-increasing attention due to their wide applications in acoustic transducers, actuators, stress sensors and so on [6][7][8][9]. Actually, enhanced magnetostriction has been found in some textured alloys, such as Fe-Ga [10][11][12][13], Terfenol-D [14,15], Ni-Mn-Ga [16,17], and Ni-Mn-In [18,19]. However, there are still some drawbacks in current magnetostrictive materials, such as high-cost (Terfenol-D), limited magnetostriction value (Fe-Ga), or irreversibility (Ni-Mn-Ga and Ni-Mn-In), which have hindered their application to a large extent.…”