Microstructure and magnetostrictive properties of Tb doped Fe–Ga bulk alloys prepared by melt quenching

Abstract

The microstructure and magnetostrictive properties were investigated in the Tb doped Fe83Ga17−xTbx (x = 0.05, 0.10, 0.20, 0.30, 0.40, 0.50) bulk rods prepared by melt rapidly quenching. The partial solid solubility of Tb in the Fe–Ga matrix was preliminary detected by the lattice parameters and SEM observation. The matrix keeps A2 structure and the second phase appears surround the grain boundary as x ≥ 0.1. \( \left\langle {100} \right\rangle \) preferred orientation is also observed for x = 0.1 sample along the axis of the quenched rod. The saturation magnetostriction first increases and maximum value reaches at x = 0.1, and then decreases with Tb addition increasing. The initial increase of the magnetostriction should be associated with the partial solution of Tb in the matrix, the maximum value at x = 0.1 should be attributed to the \( \left\langle {100} \right\rangle \) preferred orientation, and the decrease of the magnetostriction is correlated with the appearance of the second phase along the grain boundary.