Microstructure and properties of the heat treated DS Tb-Dy-Fe alloy

<110> oriented rods of a Tb-Dy-Fe magnetostrictive alloy have been successfully prepared by zone melting unidirectional solidification. A homogenization annealing for 4 or 48 h at 900-1100°C has been carried out in a quartz cylinder under Ar protection after pumping to 2x 10^-3 Pa. It was found that, after annealing, <110> preferred orientation is unchanged, the net shape pseudo-eutectic rare earth phase trends discontinuous and spheroidal, magnetostriction slightly decreased without pre-stress but increased obviously with pre-stress. An obvious magnetostriction jump effect was observed in the annealed samples. A satisfactory magnetostrictive property of 1950 × 10^-6 was obtained under 15 MPa pre-stress after 4 h heat treatment. The compressive stresses of the heat-treated samples decrease monotonously with increasing the soaking time. A satisfactory combination of the magnetostriction and mechanical properties was obtained at annealing for 4 h for the <110> oriented Tb-Dy-Fe alloy.