Magnetostrictive properties of directional solidification Fe ₈₂Ga ₉Al ₉ alloy

Fe ₈₂Ga ₉Al ₉ alloy rod was prepared by the directional solidification (DS) method. The effects of uniaxial compressive stress on magnetostriction of the alloy and the temperature dependence of magnetostriction were investigated. The results show that the magnetostriction increases from 135 × 10 ^-6 at 2.3 MPa to 221 × 10 ^-6 at 53 MPa and then remains at this value between 53 MPa and 90 MPa. This enhancement results from domain rotation under the compressive stress. The temperature dependence results show that the saturated magnetostriction decreases by 11 (25°C-120°C) and 13 (25°C-100°C) for samples with 0 MPa and 15 MPa compressive stress applied, respectively. This decrease is due to reduced magnetic crystalline anisotropy as the temperature increases. Under the compressive stress conditions, the magnetostriction decreases more notably.