Magnetism， magetostriction， and M?ssbauer effect studies of Tb0.3Dy0.6Pr0.1(Fe1-xAlx)1.95 alloys

Abstract

The effects of Al substitution for Fe on the structure， the magnetism， the magnetostriction， the anisotropy and the spin reorientation of a series of Tb0.3Dy0.6Pr0.1（Fe1-xAlx）1.95 alloys （x=0.05，0.1，0.15，0.2，0.25，0.3） at room temperature are investigated. It is found that the compositions of Tb0.3Dy0.6Pr0.1（Fe1-xAlx）1.95 substantially retain MgCu2-type C-15 cubic Laves phase structure when xx=0.2 and the mixture phase increases with x increasing. The lattice constants increase linearly， Curie temperature decreases gradually and the coercive force decreases sharply with x increasing. The vibrating sample magnetormeter measurements show that the relationship between magnetization and substitution x is rather ambiguous. The magnetostriction of the Tb0.3Dy0.6Pr0.1（Fe1-xAlx）1.95 alloys decreases drastically with x increasing and the magnetostrictive effect disappears when x>0.15. However， a small amount of Al substitution is beneficial to a decrease in magnetocrystalline anisotropy. The analysis of the Mssbauer spectra indicates that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the increase of Al concentration x，namely spin reorientation takes place, thereby leading to the change of macroscopical magnetism and magetostriction.