Magnetostriction of 〈1 1 0〉 oriented crystals in Tb _0.36Dy _0.64(Fe _1-xCo _x) ₂ (x = 0-0.30) alloys

Oriented polycrystalline rods of Tb _0.36Dy _0.64(Fe _1-xCo _x) ₂ (where x = 0.00, 0.10, 0.15, 0.20, 0.30) have been successfully prepared by zone melting unidirectional solidification with high growth velocity of 240 mm/h and 900 mm/h. The measurement results show that 〈1 1 0〉 preferred orientation can be formed in the quaternary alloys with dendritic solidified morphologies. The magnetostriction was measured as a function of applied magnetic field up to 4 kOe and compressive stresses of 5 MPa and 10 MPa over a wide temperature range from -80 to 100 °C. The magnetostriction "jump" effect was obvious in all the Tb _0.36Dy _0.64(Fe _{1- x}Co _x) ₂ 〈1 1 0〉 oriented crystals at room temperature and elevated temperature (100 °C), but not so obvious at cryogenic temperature (-80 °C). A satisfactory magnetostrictive property was obtained in the 〈1 1 0〉 oriented Tb _0.36Dy _0.64(Fe _0.85Co _0.15) ₂ crystal with the value of 1810 × 10 ^-6 under 14 MPa pre-stress and 5 kOe magnetic field at room temperature.