| 摘要 |
PROBLEM TO BE SOLVED: To provide soft magnetic powder that can achieve high packing density, when the powder is molded in a mould and to provide a dust core obtained, by using the powder and has high permeability and a high magnetic flux density. SOLUTION: The thickness of an oxide coating film formed on the surface of a Fe-Si-Al alloy powder, composed of 0.5-15 wt.% Si, 0.5-10 wt.% Al, and the balance being substantially Fe is adjusted to <=0.05 μm and the thickness, and aspect ratio of the alloy powder are respectively adjusted to 10-30 μm and 3-20. The dust core is obtained by kneading the alloy powder with a binder component, composed mainly of a phosphate and water glass and compression- molding the kneaded product. The dust core has a permeability of >=125 at a frequency of 100 kHz, a magnetic flux density of >=0.6 T under impressed magnetic field of 10,000 A/m, and electrical resistivity of >=0.03 Ω.m. |
