METHOD OF MEASURING MAGNETIC VISCOSITY OF FERROMAGNETICS Russian patent published in 2009 - IPC G01N27/76 G01R33/16 

FIELD: instrument making.

SUBSTANCE: invention relates to area of measuring techniques and can be used for development of power devices exploiting magnetic viscosity of ferromagnetic. The proposed method consists in that the ferrite ring is used to form a high-frequency generator oscillating circuit. A part of the said ferrite ring, for example, one its half, is placed into a continuously induced permanent magnetic field, i.e. a magnetic bias field with intensity corresponding to the maximum relative magnetic permeability of aforesaid part of the ferrite ring. Note that the latter is subjected to the effect of additional pulsed magnetic field to cause its deep saturation at which relative magnetic permeability of the ferrite ring decreases by more, than an the order of magnitude relative to its maximum. Now the time interval between consecutive origination of two fixed frequencies at the HF-generator, two high-frequency comparators connected to HF-generator having been preliminary tuned to. The Hall pickup is used to determine the pulsed field set-up time constant, the said magnetic field acting upon aforesaid part of the ferrite ring. Finally, the ferromagnetic magnetic viscosity is calculated.

EFFECT: higher accuracy of ferromagnetic magnetic viscosity automated measurements.

2 dwg