フェライト系PMステンレス鋼の交流磁気特性に及ぼす残留気孔の影響 Effect of Residual Pores on AC Magnetic Properties of PM Ferritic Stainless Steels
A fundamental study was made on the AC magnetic properties and core loss of the two PM stainless steels with some residual pores. In this case, powder particle size and sintering conditions (1373-1573K×20-240min) were employed as parameters to the residual pore morphologies of sintered materials, as seen in the previous report.<BR>The results were summarized as follows:<BR>(1) The maximum flux density (Bm) and specific permeability (μa) wholly depend on the frequency (∝f<SUP>-1/2</SUP>), owing to the penetration depth of field.<BR>(2) As for a given frequency, μa complicatedly varies with sintered density under the reciprocal influence of DC magnetic properties and electrical resistance.<BR>(3) The DC relationship between the maximum permeability (μm) and sintered density is fairly held on the AC one in the low frequency region, as a function of powder particle size and sintering conditions.<BR>(4) At higher frequency, μa and Bm (almost directly proportional to μa) show the maximum value in. the critical sintered density, as the case may be.<BR>(5) The core loss behaves apparently as well as μa in the relation to sintered density and, consequently, is enhanced with the increase of Bm and reduced with the increase of electrical resistivity (ρ).
粉体および粉末冶金 45(10), 937-943, 1998-10-15
Japan Society of Powder and Powder Metallurgy