Tailoring magnetostriction with various directions for directional solidification Fe82Ga15Al3 alloy by magnetic field heat treatment

Abstract

The magnetostriction of the Fe82Ga15Al3 alloy, along the length and width, can be tailored by applying a magnetic field heat treatment. In this work, the Fe82Ga15Al3 sheet was cut from the directional solidified Fe82Ga15Al3 alloy with the ⟨100⟩ preferred orientation and was annealed at 720 °C for 30 min under a magnetic field of 800 Oe along the length direction with a heating and cooling rate of 100 °C/min. The magnetostrictive properties along the length and width directions were modified to λ// = 7 ppm and λ⊥ = −210 ppm from λ// = 210 ppm and λ⊥ = −10 ppm for the initial sample prior to the magnetic field heat treatment. The cellular-like magnetic domain structure was composed of parallel 180° stripe domains and vertical 90° domains observed using a magnetic-force microscope. The change in magnetostriction along parallel and perpendicular directions was mainly resulted from the rotation of the magnetic domain units.

Influence of External Static Magnetic Fields on Properties of Metallic Functional Materials

“…Therefore, SMF has extensive applications in the solid-solid phase transformations to alter the transformation temperatures, the phase constitutions and selection, the phase morphology and disorder-order transition [29,30]. Moreover, magnetic field annealing has been confirmed to enhance the performances of some magnetostrictive materials [31,32]. It is the purpose of the present work, to compare the effects of SMFs to magnetostriction of Fe-Ga alloys in solidifying and/or annealing processing.…”

Magnetic Domain Structures in Fe-Ga Alloys

“…Bai et al demonstrated a series of stripe or maze domain structures in galfenol alloys with a size of a few microns [33,34]. Many other authors [35][36][37][38][39][40][41][42][43][44] have reported similar structures. These observations account for the bulk of the literature on magnetic domains in galfenol.…”