TENSOR MAGNETIC HYSTERESIS LOOP MEASUREMENTS OF A STEEL CUBE

The change in magnetic moment of a 25.4 mm steel cube sample was measu red in three orthogonal directions with fields up to magnetic saturati on applied in each of the three cube directions. An analysis of the di agonal components of the resulting 3x3 tensor indicated the relative m agnetic easy axis amongst the three directions measured. Additional in formation on the magnetization processes was obtained from an analysis of the off-diagonal changes in the magnetic moment tenser. Hysteresis was also observed in these off-diagonal loops, A net magnetization ve ctor of magnitude M was considered. Deviations of magnetization compon ents from linearity along the diagonal directions, Delta M(iI), were r elated to the off-diagonal components, M(iJ) and M(iK), by the simple relation Delta M(iI) approximate to +/-(M(iJ)(2) +M(iK)(2))/wM, where i is the field direction x, y, or z and I, J, and K cyclic coordinates X, Y, and Z indicating the magnetization components measured by coils X, Y, and Z, respectively. Changes in the off-diagonal components wer e associated with various field dependent magnetization processes such as domain wall motion and domain vector rotation. The asymmetry of th e magnetic hysteresis loop tensor is associated with either a texture of the material or the existence of internal stresses.