Determination of anisotropy parameters in magnetically uniaxial specimens by torque derivatives

Formulae are given for determination, from torque curve slopes, of the first- and second-order anisotropy parameters in magnetically uniaxial specimens. The customary situation in which torque is plotted versus applied magnetic field orientation angle is examined. Corrections to measured torque slope arise from the off-set of the magnetization vector
\overrightarrow{M}_{s}
, from the applied magnetic field
\overrightarrow{H}
direction.