In this study, Sendust (Fe85Si9.6Al5.4) nanostructure alloy was prepared by
mechanical alloying and was characterized by X-ray diffraction. In addition, the alloy’s
morphology and its distribution particle size were investigated by scanning electron
microscopy method. The alloyed powders were insulated with 4wt% of three different
insulating materials including polyvinyl alcohol, epoxy resin, and sodium silicate. Then,
0.5 wt% zinc stearate was added as a lubricant and the composites were formed at a
pressure of 1600 MPa in a torodial die. These cores were annealed in Ar atmosphere at
350 to 450 ºC for 1 h. Some of the magnetic parameters of the as-milled and annealed
samples were measured and compared with each other in the frequency range of 4 to
1000 kHz. The results showed that polyvinyl alcohol is not a suitable insulating agent
for insulating this alloy. In addition, the real part of the initial magnetic permeability of
the magnetic powder core insulated by sodium silicate in comparison with that insulated
by epoxy resin is a bit smaller, but more reduction of the imaginary part of former
results in an increase the Q-factor throughout measuring frequency range. The results
show that annealing is more effective on improvement of the measured magnetic
properties of the samples insulated with sodium silicate than that insulated with epoxy
resin. پرونده مقاله