| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for improving iron loss by forming an extra thin oxide layer on the surface of a foil by carrying out atmosphere control according to the temperature of the foil in the course of casting. SOLUTION: An alloy which has a composition represented by Fea Sib Bc Cd [where the symbols (a), (b), (c), and (d) satisfy, by atomic%, 70<=a<=86, 1<=b<=19, 7<=c<=20, 0.02<=d<=4, and a+b+c+d+100, respectively] is melted, and the resultant molten alloy is sprayed through a slot nozzle onto a moving cooling substrate and rapidly solidified to manufacture an amorphous foil. In this method for manufacturing an amorphous foil, foil tempratures are measured at least at two spots in the longitudinal direction of the foil in the course of casting, and a region of foil where foil temperature is within the temperature range of the whole or a part of 800 to 150 deg.C is held in an atmosphere containing 1 to 30 vol.% oxygen and a region of foil having a temperature outside the above temperature range is held in a nonoxidizing atmosphere. |
