Magnetic Properties of the Fe2B Alloy Doped with Transition Metal Elements

The intrinsic magnetic properties (magnetic moments, magneto-crystalline anisotropy, Curie temperatures) of the (Fe1-xMx)(2)B alloys have been calculated using the spin-polarized relativistic Korringa-Kohn-Rostoker (SPR-KKR) band structure method. The transition metal elements M (M = Co, Ni, Mo, Ta, W and Re) considered in the present study are reported to form stable M2B or FeMB alloys with a tetragonal Cu2Al structure type. The experimental studies show that the Fe2B alloy has a large magnetization (173 Am-2/kg), a large Curie temperature (1017 K) and a relatively large anisotropy constant K-1 (-0.80 MJ/m(3)), but the alloy is inappropriate for permanent magnet applications due to in-plane easy magnetization axis (EMD). The present investigations show the magnetocrystalline anisotropy behaviour by doping with selected d-elements aiming to find an appropriate dopant which is able to switch the EMD from planar to axial and to enhance the magnetocrystalline anisotropy energy (MAE) value without a major decrease of magnetization and Curie temperature.