Magnetostriction in twinned [112] crystals of Tb.27Dy.73Fe2

The magnetostrictive properties of cubic Laves phase Tb
0.27
Dy
0.73
Fe
2
prepared by (a) Czochralski and (b) a free standing r.f. zone method, were examined. Crystals were found to grow preferentially along [
11\bar{2}
] in twinned dendrite sheets with [111] normal. The saturation magnetostriction along [111] is very large (
\lambda_{111} = 1640 \times 10^{-6}
), in excellent agreement with that of single crystal Tb
.27
Dy
.73
Fe
2
. The magnetostriction along [
11\bar{2}
] is larger than expected. For magnetic fields less than 2000 Oe, the magnetostriction is much smaller, presumably due to internal energy stored at the twin boundaries.