A graphical method to determine high-order anisotropy constants of uniaxial anisotropic material from single-crystal magnetization curves

In a uniaxial magnetic anisotropy system, the magnetization vector is proved to rotate on the plane made by easy axis and the applied field direction during the initial magnetization process. Under this restricted condition, a method to analyze high-order anisotropy constants from magnetization curves of single crystal measured in basal plane is suggested. Especially, the special curves on hard and easy directions within basal plane are proved to give the most reliable results in this method. Using the method, the anisotropy constants of Pr2Fe14B at 290 K were determined as K-1 = 5.7 x 10(7) erg/cm(3), K-2 = -0.26 x 10(7) erg/cm(3), K-3 = 0.12 x 10(7) erg/cm(3), K-4 = 0.21 X 10(7) erg/cm(3) and K-5 = -0.12 x 10(7) erg/cm(3). Simulated magnetization curves using these anisotropy constants coincide well with experimental data. (C) 1998 Elsevier Science B.V. All rights reserved.