| 摘要 |
PURPOSE:To obtain an iron-base amorphous alloy foil capable of stably revealing superior magnetic properties by limiting the thickness of an alpha-Fe surface crystalline layer formed on a surface to the prescribed value or below in the annealing stage to be applied after rapid solidification. CONSTITUTION:A molten Fe-B-Si alloy which has a composition containing, preferably, 7-16at% B and 4-14at% Si, further containing, if necessary, <=3at% Cu, and having the balance essentially Fe is subjected to rapid solidification. Subsequently, the above alloy foil prepared by means of rapid solidification is annealed in a temp. range of about 350-400 deg.C in which dew point is controlled to <=30 deg.C, by which, in the above annealing stage, an alpha-Fe surface crystalline layer of <=300Angstrom thickness is formed on the surface of the above alloy foil. The resulting iron-base amorphous alloy foil shows superior magnetic properties inherent in the material without causing dispersion of magnetism. |
