| 摘要 |
PURPOSE:To increase the residual magnetic flux density and to decrease the coercive force by having an Fe-B-C based alloy sheet undergo a heat treatment at a temperature close to the beginning temperature of thermogram heat absorption in the alloy's thermogram curve. CONSTITUTION:Molten metal of an Fe-B-C alloy consisting of: B; 12-16atomic%, C; 3-8atomic%, the sum of B and C; 19-21atomic%, and the remaining Fe is rapidly cooled by bringing it contact with the surface of a high-speed rotating roll, thereby producing a 10-50mum thick sheet having amorphous state at one side. The sheet is wound on a silica bobbin in troidal state at the temperature range within + or -25 deg.C of thermogram heat absorption beginning temperature Ta of the alloy's thermogram curve, then is maintained at 270-390 deg.C for one hour, and cooled to room temperature at a rate 15 deg.C/min. This process increases the residual magnetic flux of the sheet and decreases the coercive force. |
