| 摘要 |
PURPOSE:To manufacture a material having superior D.C. magnetic properties and reduced in high frequency loss by cold-rolling an Fe-Ni alloy to a specific thickness, applying magnetic annealing to the resulting cold-rolled sheet, and then subjecting the above to cold working and annealing treatment under respectively specified conditions to form a sheet metal of a specific thickness. CONSTITUTION:An Fe-Ni alloy is refined and cast into an ingot, which is cold- rolled to <=100mu thickness and then subjected to magnetic annealing consisting of holding in a nonoxidizing atmosphere of dry oxygen, etc., at >=about 1,000 deg.C for >=about 10min and cooling down to room temp. Subsequently, the above sheet is subjected to slight-degree cold working at <=10% draft and then to annealing treatment consisting of holding in a nonoxidizing atmosphere of dry oxygen, etc., at >=700 deg.C for >=5min and cooling down to room temp. The above slight-degree working and annealing treatment are alternately applied once or plural times, respectively, to form a sheet metal of <50mu thickness. By this method, an extra thin magnetic sheet metal (foil) material increased in average crystalline grain size and remarkably improved in D.C. and A.C. magnetic properties can be obtained. |
