Magnetic properties of Fe-Si alloys by powder metallurgy

Fe-Si alloys with 1 to 5 wt%Si sintered at the temperature range from 1150 to 1450°C were investigated to improve the magnetic properties of the Fe-Si sintered materials for making them applicable to cores, pole-pieces, armatures and inductors. The magnetic properties of the Fe-Si alloys with 2 to 3 wt%Si sintered at the temperature range from 1400 to 1450°C are superior to the other Fe-Si sintered alloys and almost comparable to the Fe-Si wrought alloy except for the maximum permeability. By microscopy and electron microprobe analysis, it is clarified that the difference of permeability between the sintered alloy and the wrought alloy is attributed to the presence of pores and SiO2particles in grains as well as at grain boundaries in the sintered alloy.