| 摘要 |
PURPOSE:To manufacture iron powder having high saturation magnetization, low coercive force and excellent magnetic shield characteristic by executing heat treatment to the specific particle size of scaly iron powder incorporating the specific quantities of B, Si, Cr and Nb, at the specific temp. CONSTITUTION:To the particle diameters obtd. with particle size distribution meter in the scaly alloy iron powder having 18 - 33 atm% total of B and Si, 2 - 12 atm% total of Cr and Nb and 0.02 - 0.6mum average thickness (d), at the time of using D50 and D90 for the particle diameters of 50% and 90% accumlating the wts. from small particle diameter, respectively, the heat treatment is executed to the powder having D50: 10 - 40 mum and D90: 20 - 80mum and shape of aspect ratio (D50/d): 20 - 500, at 300 - 550 deg.C. Peak in the range of 20 - 80 deg. angle 20theta of diffraction in X-ray diffraction pattern obtd. by executing the X-ray diffraction with Cu-Ka ray to this powder, shows single peak and at the time of defining strength Ir of the single peak with the equation I, this is Ir > 6 and the scaly iron powder for magnetic shield composed of soft isomagnetic body is obtd. |
