Composition anisotropy compensation and magnetoelastic properties of Mn-doped TbxHo1−xFe2 Laves compounds (0.08 ≤ x ≤ 0.16)

Abstract The structural, magnetic and magnetoelastic properties of Tb x Ho 1−x Fe 1.9 Mn 0.1 (0.08 ≤ x ≤ 0.16) alloys have been investigated by means of X-ray diffraction (XRD), Mossbauer spectra, a vibrating sample magnetometer and a standard strain technique. The easy magnetization direction (EMD) at room temperature rotates continuously from the 〈100〉 axis for x = 0.10 to 〈111〉 for x = 0.14 through an intermediate direction around x = 0.12, subjected to the anisotropy compensation between Tb 3+ and Ho 3+ ions. The magnetocrystalline-anisotropy compensation can be obtained by performing XRD on magnetic-field aligned powders and by evaluating the EMD, magnetization process and magnetostriction. The compensation point achieved is around x = 0.12, shifting to the Ho-rich side at room temperature compared with the Mn-free system. Mn causes opposite contributions to the resultant anisotropy of the alloys as compared to Ho. A minimum in anisotropy is obtained for the Tb 0.12 Ho 0.88 Fe 1.9 Mn 0.1 compound, which has a high low-field magnetostriction (λ a  ∼ 340 ppm @ 2 kOe).