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US 4,257,830 AGranted
Method of manufacturing a thin ribbon of magnetic material
AssigneeNoboru Tsuya
InventorsNoboru Tsuya, Kenichi Arai
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AssigneeNoboru Tsuya
InventorsNoboru Tsuya, Kenichi Arai
Estimating the term…
A method of manufacturing a thin ribbon of magnetic material having a high permeability and excellent flexibility and workability comprising the combination of steps of melting a magnetic material consisting of essentially of by weight 4-7% of aluminum, 8-11% of silicon and the remainder substantially iron and inevitable impurities at a temperature of between a melting point and a temperature not exceeding 300.degree. C. from the melting point, and necessary subingredient of less than 7%, ejecting thus obtained melt under a pressure of 0.01-1.5 atm. through a nozzle onto a moving or rotating cooling substrate, cooling super-rapidly the melt on the rotating surface of said cooling substrate at a cooling rate of 10.sup.3 -10.sup.6 .degree. C./sec so as to have a high initial permeability of more than 10.sup.4, a low coercive force of less than 0.10 Oe and an excellent flexibility, forming a thin ribbon having a compact and fine grain size structure substantially without existing of the ordered lattice, and annealing thus obtained thin ribbon at a temperature of between 600.degree. to 1,000.degree. C. for 1 minute to 5 hours, more preferably 1 to 100 minutes so as to obtain a columnar crystal structure by promoting the growth of crystal grain size.
A method of manufacturing a thin ribbon of magnetic material having a high permeability and excellent flexibility and workability comprising the steps of:
A method as defined in claim 9, wherein the nozzle is lined with boron nitride in at least the edge and inner edge portion of nozzle.
A method of manufacturing a thin ribbon of magnetic material having high permeability and excellent flexibility and workability comprising the steps of:
A thin ribbon of magnetic material having a high permeability, excellent flexibility and workability consisting essentially of by weight 4-7% of aluminum, 8-11% of silicon and the remainder being iron and inevitable impurities and having a compact fine grain structure with a mean grain diameter from about 1 to 100 .mu.m, wherein the fine crystal grains are essentially of columnar grain structure aligned perpendicular to the surface of the thin ribbon.
A thin ribbon of magnetic material having a compact fine grain crystal structure, a high permeability, excellent flexibility and workability, consisting essentially of by weight 4-7% of aluminum, 8-11% of silicon, at least one element selected from the group consisting of 0.01-2% of maganese, 0.01-10% of cobalt and 0.01-3% of nickel and the remainder being iron and inevitable impurities, wherein the compact fine grain crystal structure is composed essentially of columnar grains aligned perpendicular to the surface of the thin ribbon and has a mean grain diameter of from about 1 to 100 .mu.m.
A magnetic recording and reproducing head comprising at least one thin ribbon of a magnetic material consisting essentially of by weight 4-7% of aluminum, 8-11% of silicon and the remainder being iron and inevitable impurities of less than 0.5% having a compact fine grain crystal structure, wherein the compact fine grain crystal structure is composed essentially of columnar grains aligned perpendicular to the surface of the thin ribbon and having a mean grain diameter of from about 1 to 100 .mu.m.
A magnetic recording and reproducing head as defined in claim 23, wherein said thin ribbon is annealed at a temperature of 600.degree.-1,000.degree. C. from about 1 minute to 5 hours after forming a magnetic recording and reproducing head whereby said thin ribbon has an ordered lattice, more than 500 of Vickers hardness and a mean grain diameter of from about 1 to 100 .mu.m.
A thin ribbon of magnetic material having a high permeability, excellent flexibility and workability consisting essentially of by weight 4-7% of aluminum, 8-11% of silicon and the remainder being iron and inevitable impurities and having a crystal grain structure with ordered lattice having a mean grain size of 0.01-10 mm, wherein the crystal grains are promoted to a columnar grain structure aligned perpendicular to the surface of the thin ribbon and having a grain size of from about 0.01-10 mm.
Dependencies are inferred from the claim text.