| 摘要 |
PURPOSE:To produce a 'Permalloy(R)' excellent in impedance relative magnetic permeability by subjecting a sheet of 'Permalloy(R)' containing specific amounts of Mo or further Cu to magnetic annealing and to rapid cooling under respective ly specified conditions. CONSTITUTION:An ingot of a 'Permalloy(R)' which has a composition consisting of, by weight, 75-85% Ni, 4-6% Mo, and the balance Fe or further containing 4-6% Cu is hot-rolled, or a molten 'Permalloy(R)' is formed into a sheet by a direct continuous casting process. After hot rolled sheet annealing is done at >=900 deg.C, metal oxides are removed from the surface. This 'Permalloy(R)' sheet is cold-rolled once or cold-rolled twice or more while process-annealed between the cold rolling stages and worked to the final sheet thickness. Then, a separation agent at annealing, such as alcohol slurry of alumina, is applied and magnetic annealing is done in a hydrogen-containing atmosphere at >=1000 deg.C. The cooling rate in the range between 600 and 300 deg.C in the latter stage of this annealing is controlled to (100 to 400) deg.C/hr, by which the 'Permalloy(R)' sheet excellent in magnetic properties, particularly in impedance relative magnetic permeability, can be produced. |
