Mn substitution effect on the magnetic properties of PrFe1.9 alloy

Polycrystalline magnetostrictive alloys Pr(Fe1−xMnx)1.9 (0⩽x⩽0.2) were synthesized by high-pressure annealing. X-ray diffraction results show that all the samples exhibit cubic Laves phase with MgCu2-type structure. The lattice parameter increases with increasing Mn concentration while the Curie temperature decreases. The saturation magnetization decreases with increasing Mn concentration, which can be understood on the basis of the rigid band model. The magnetizations of the samples with x=0.05 and x=0.1 are easy to get saturated in comparison with that of the sample without Mn, which implies that small amount of substitution Mn for Fe can lower the magnetic anisotropy of the alloy. The saturation magnetostriction decreases monotonously with increasing Mn content, while the magnetostriction of the sample with x=0.1 shows a peak at low magnetic fields.