The magnetostriction and magnetic softness of rapidly quenched (Tb0.3Dy0.7)Fe2 alloys prepared at various quenching rates were investigated. The magnetic softness of magnetostriction was estimated from both the residual magnetostriction, λR, measured in a remanent state and the phenomenological softness parameter, H'c. The value of λR increases monotonically from 100 × 10-6 to 700 × 10-6 with incresing roll velocity VRoll. The parameter H'c exhibits a maximum of 0.7 kOe at values of VRoll between 15 and 20 m/s. The magnetostriction measured at 20 kOe, λ20k, exhibits abroad minimum as a function of VRoll. Both λ20k and H'c depend mainly on the preferred orientation of the ribbons. A value of 580 × 10-6 for λ// was obtained at 0.5 kOe; this is comparable with the value for a single crystal sample.
