The microstructure and magnetic properties of TbDyHo(FeMn)_(1.95) alloys

摘要

The composition dependence of crystal structure, lattice parameter, micromorphology, Curie temperatures, magnetocrystalline anisotropy constant of Tb_(0.29)Dy_(0.48)Ho_(0.23)(Fe_(1-X)Mn_X)_(1.95) (x≤0.3) alloys were investigated by the experiment. X-ray diffraction patterns demonstrate the Tb_(0.29)Dy_(0.48)Ho_(0.23)(Fe_(1-X)Mn_X)_(1.95) (x≤0.3) alloys possess MgCu_2-type cubic Laves structure. The lattice parameter of Tb_(0.29)Dy_(0.48)Ho_(0.23)(Fe_(1-X)Mn_X)_(1.95) alloy increases with increasing of x value. The Curie temperature Tc decreases from 375°C for x=0 to 316°C for x=0.05, 265°C for x=0.1. The magnetocrystalline anisotropy constant K1 of Tb_(0.29)Dy_(0.48)Ho_(0.23)(Fe_(1-X)Mn_X)_(1.95) (x≤0.3) decreases slightly with the increasing of x value. The magnetostriction was examined under applied magnetic field H in the room temperature. The Tb_(0.29)Dy_(0.48)Ho_(0.23)(Fe_(1-X)Mn_X)_(1.95) (x≤0.2) alloys have the character of giant magnetostrictive in room temperature. With the increasing of Mn concentration, the magnetostrictive of Tb_(0.29)Dy_(0.48)Ho_(0.23)(Fe_(1-x)Mn_x)1.95 (x≤0.2) alloy decreased.