In this paper, the authors described a change in the leakage flux from the torque-applied and DC-excited FeCoV magnetic alloy wires. The experiments resulted that the leakage flux decreased when torque was applied to the measurement sample. This is considered to be due to a change in permeability caused by the application of shear stress to the magnetostrictive FeCoV. It was also found that repeated measurements confirmed that the initial state (i.e., no torque applied) of the sample contributed significantly to the change in leakage flux, and furthermore, the magnetic properties of the torquer fixture may be involved in the magnetic circuit.
Kameshima et al. (Tue,) studied this question.