Iron-silicon-aluminum alloy is an alloy powder of 85% iron, 9% silicon and 6% aluminum. It is processed into a ring or E-type magnetic powder core by special process. It is commonly called Kool Mμ magnetic powder core or Sendust magnetic powder core. .
Due to its high hardness and high electrical resistivity, iron-silicon-aluminum alloy is suitable for use as a video head material. The high hardness guarantees a long service life and good image recording and playback quality. The high resistivity makes it have higher magnetic permeability than other magnetic alloys when operating at high frequencies.
Since the iron silicon aluminum alloy sample sheet is very brittle, it is not possible to directly wind the measuring coil around the sample. The sample protection box must be made of insulating material such as plexiglass. The coil is wound around the protective case containing the sample and a void flux is introduced into the measurement.
Generally, in the test of a high magnetic permeability alloy, since the magnetic permeability of the sample is much larger than the magnetic permeability of the air, the contribution of the void magnetic flux is relatively small and negligible. However, the ferrosilicon aluminum alloy has a low magnetic permeability at high frequencies, and the void flux must be corrected.