Rotational hysteresis loss in grain-oriented silicon-iron

An improved torque magnetometer has been used to measure accurately the rotational hysteresis loss in grain-oriented silicon-iron for various percentage orientations and thicknesses. The experimental results are discussed in terms of multi-domain concepts and of the Stoner-Wohlfarth single-domain particle, of which the rotational-hysteresis behaviour has been evaluated. The possible relevance of this theory and its extensions to the experimental results are considered.