Magnetocrystalline anisotropy of Ho-2(Co1-xFex)(15)Al-2 compounds

The structure and magnetic properties of Ho-2(Co1-xFex)(15)Al-2 compounds w ith x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.6, 0.8, 1.0 have been investigated by x- ray diffraction (XRD) and magnetization measurements. XRD patterns demonstr ate that all samples are single phase with the hexagonal Th2Ni17-type struc ture. The substitution of Fe for Co leads to a nearly linear increase in th e unit cell volume and a monotonic decrease of Curie temperature. Saturatio n magnetization increases with x and then decreases, attaining a maximum at x = 0.2. The magnetic anisotropy phase diagram of Ho-2(Co1-xFex)(15)Al-2 c ompounds has been determined from the temperature dependence of magnetizati on and the XRD patterns of magnetically oriented powder samples. The spin-r eorientation temperature of Ho-2(Co1-xFex)(15)Al-2 compounds was found to d ecrease firstly with Fe content increasing for x < 0.1 and then increase fo r 0.1 < x < 0.4, attaining a lowest value of 381 K at x = 0.1.