<001> oriented single crystal growth and magnetostriction of Fe₈₁Ga₁₉ alloys

The Fe₈₁Ga₁₉ single crystals were grown in a floating zone melting furnace at a growth rate of 4 mm/h by using a seed crystal. A single crystal was grown by using the seed crystal oriented 5° from the <001> orientation. Pole figure tests were taken at different parts of the single crystal and showed that the start and end parts' axial orientations were 5° and 4° from the <001> orientation, respectively. Another single crystal was grown by using the seed crystal oriented <001> orientation. Magnetostrictive properties along the axis of the crystals λ_// were measured for the single crystal, and the saturated magnetostriction λ_// up to 0.0324% was achieved under the pre-stress of 60 MPa. Initial magnetization curves were measured in single crystals along <100>, <110> and <111> axis, respectively. From the magnetization curves, magnetocrystalline anisotropy constants of Fe₈₁Ga₁₉ alloys were calculated, and the values of K₁ and K₂ were 1.3 × 10⁴ and -2.6 × 10⁴ J/m³, respectively.