US4265682A — High silicon steel thin strips and a method for p…

Claim 1

Independent Claim 98 words

A method of producing a thin strip of high silicon steel having excellent magnetic properties and good workability comprising the combination of steps of: preparing a high silicon steel melt having a composition consisting essentially of 4-10% by weight of silicon, less than about 2% of aluminum and the remainder being iron and incidental impurities, cooling the melt to about 400° C. on a cooling substrate at a cooling rate of from about 10 3 to 10 6 °C./sec. to form a thin strip having micro-structure comprising very fine crystal grains without ordered lattics of Fe 3 Si.

Claim 2

Independent Claim 98 words

A method of producing a thin strip of high silicon steel having excellent magnetic properties and good workability comprising the combination of steps of: preparing a high silicon steel melt having a composition consisting essentially of 4-10% by weight of silicon, less than about 2% of aluminum and the remainder being iron and incidental impurities, cooling the melt to about 400° C. on a cooling substrate at a cooling rate of from about 10 3 to 10 6 °C./sec. to form a thin strip having micro-structure comprising very fine crystal grains without ordered lattics of Fe 3 Si.

Claim 3

Dependent Claim 59 words

A method as defined in claim 1, wherein the composition of said melt consists essentially of 4-7% by weight of silicon and in percent by weight at least one element selected from the group consisting of less than 2% of manganese, less than 10% of cobalt, and less than 3% of nickel the remainder being iron and incidental impurities.

Claim 4

Dependent Claim 23 words

A method as defined in claim 1, wherein the melt is cooled by ejecting the melt onto a moving surface of cooling substrate.

Claim 5

Dependent Claim 34 words

A method as defined in claim 3, wherein the melt is ejected through a nozzle having a plurality of nozzle holes arranged adjacent to each other in the lateral direction of a thin strip.

Claim 6

Dependent Claim 30 words

A method as defined in claim 4, wherein the melt is ejected under vacuum or protective atmosphere selected from the group consisting of argon, nitrogen, carbon dioxide or mixture thereof.

Claim 7

Independent Claim 127 words

A method of producing a thin strip of high silicon steel having excellent magnetic properties and good workability comprising the steps of: preparing a high silicon steel melt having a composition consisting essentially of 4-10% by weight of silicon less than about 2% of aluminum and the remainder being iron and incidental impurities, cooling the melt to about 400° C. on a cooling substrate at a cooling rate of from about 10 3 to 10 6 °C./sec. to form a thin strip having micro-structure consisting of very fine crystal grains without ordered lattices of Fe 3 Si, subjecting the thus obtained strip to further annealing at a temperature of 400°-1,300° C. for 1 minute to 5 hours so as to promote the grain growth to 0.05-10 mm.

Claim 8

Independent Claim 127 words

A method of producing a thin strip of high silicon steel having excellent magnetic properties and good workability comprising the steps of: preparing a high silicon steel melt having a composition consisting essentially of 4-10% by weight of silicon less than about 2% of aluminum and the remainder being iron and incidental impurities, cooling the melt to about 400° C. on a cooling substrate at a cooling rate of from about 10 3 to 10 6 °C./sec. to form a thin strip having micro-structure consisting of very fine crystal grains without ordered lattices of Fe 3 Si, subjecting the thus obtained strip to further annealing at a temperature of 400°-1,300° C. for 1 minute to 5 hours so as to promote the grain growth to 0.05-10 mm.

Claim 9

Independent Claim 127 words

A method of producing a thin strip of high silicon steel having excellent magnetic properties and good workability comprising the steps of: preparing a high silicon steel melt having a composition consisting essentially of 4-10% by weight of silicon, less than about 2% of aluminum and the remainder being iron and incidental impurities, cooling the melt to about 400° C. on a cooling substrate at a cooling rate of from about 10 3 to 10 6 °C./sec. to form a thin strip having micro-structure consisting of very fine crystal grains without ordered lattices of Fe 3 Si, wherein the thus obtained strip is further rolled at least at a reduction rate of 5%, and annealed at a temperature of 400°-1,300° C. for 10 minutes to 5 hours.

Claim 10

Independent Claim 127 words

A method of producing a thin strip of high silicon steel having excellent magnetic properties and good workability comprising the steps of: preparing a high silicon steel melt having a composition consisting essentially of 4-10% by weight of silicon, less than about 2% of aluminum and the remainder being iron and incidental impurities, cooling the melt to about 400° C. on a cooling substrate at a cooling rate of from about 10 3 to 10 6 °C./sec. to form a thin strip having micro-structure consisting of very fine crystal grains without ordered lattices of Fe 3 Si, wherein the thus obtained strip is further rolled at least at a reduction rate of 5%, and annealed at a temperature of 400°-1,300° C. for 10 minutes to 5 hours.

Claim 11

Dependent Claim 36 words

The method of claim 1, wherein the melt of high silicon steel is maintained at a temperature of from its melting point to a temperature 300° C. higher than its melting point to control melt viscosity.

Claim 12

Dependent Claim 87 words

A thin strip of high silicon steel having excellent magnetic properties and good workability, having composition consisting essentially of by weight 4-10% of silicon, less than about 2% of aluminum and the remainder being iron and incidental impurities and having a micro-structure consisting of very fine crystal grains without ordered lattices of Fe 3 Si, wherein the fine crystal grains are essentially columnar grains aligned in a direction perpendicular to the surface of the thin strip and have a mean grain diameter of from about 1-100 μm.

Claim 13

Dependent Claim 87 words

A thin strip of high silicon steel having excellent magnetic properties and good workability, having composition consisting essentially of by weight 4-10% of silicon, less than about 2% of aluminum and the remainder being iron and incidental impurities and having a micro-structure consisting of very fine crystal grains without ordered lattices of Fe 3 Si, wherein the fine crystal grains are essentially columnar grains aligned in a direction perpendicular to the surface of the thin strip and have a mean grain diameter of from about 1-100 μm.

Claim 14

Dependent Claim 41 words

A thin strip as defined in claim 9, which also includes in percent by weight at least one element selected from the group consisting of less than 2% of manganese, less than 10% of cobalt, and less than 3% of nickel.

Claim 15

Dependent Claim 24 words

A thin strip as defined in claim 9, wherein said incidental impurities are less than 0.1% in total of carbon, nitrogen, oxygen and sulfur.

Claim 16

Dependent Claim 22 words

A thin strip as defined in claim 9, wherein the silicon is present in an amount of from about 5-7% by weight.

Claim 17

Dependent Claim 79 words

A thin strip of high silicon steel having excellent magnetic properties and good workability, having a composition consisting essentially of 4-10% by weight of silicon, less than about 2% of aluminum and the remainder being iron and incidental impurities and having a micro-structure consisting of very fine grains having a mean grain diameter of 0.05-10 mm, which is obtained by annealing a thin strip having a micro-structure consisting of very fine grains without ordered lattices of Fe 3 Si.

Claim 18

Dependent Claim 79 words

A thin strip of high silicon steel having excellent magnetic properties and good workability, having a composition consisting essentially of 4-10% by weight of silicon, less than about 2% of aluminum and the remainder being iron and incidental impurities and having a micro-structure consisting of very fine grains having a mean grain diameter of 0.05-10 mm, which is obtained by annealing a thin strip having a micro-structure consisting of very fine grains without ordered lattices of Fe 3 Si.

Claim 19

Dependent Claim 85 words

A core for electrical devices manufactured by laminating thin high silicon electrical steel sheets having a composition consisting essentially of 4-10% by weight of silicon, less than about 2% aluminum and the remainder being iron and incidental impurities and having a micro-structure comprising very fine crystal grains without lattices of Fe 3 Si, wherein the fine crystal grains are essentially columnar grains aligned in a direction perpendicular to the surface of the thin strip and have a mean grain diameter of from about 1-100 μm.

Claim 20

Dependent Claim 85 words

A core for electrical devices manufactured by laminating thin high silicon electrical steel sheets having a composition consisting essentially of 4-10% by weight of silicon, less than about 2% aluminum and the remainder being iron and incidental impurities and having a micro-structure comprising very fine crystal grains without lattices of Fe 3 Si, wherein the fine crystal grains are essentially columnar grains aligned in a direction perpendicular to the surface of the thin strip and have a mean grain diameter of from about 1-100 μm.

Claim 21

Dependent Claim 35 words

A core as defined in claim 14, wherein the core is annealed at a temperature of 400°-650° C. for 10 minutes to 5 hours so as to form an ordered lattice in the crystal grains.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1984-05-04	1984-11-03	1985-05-05	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1988-05-04	1988-11-03	1989-05-05	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1992-05-04	1992-11-03	1993-05-05	$7700.00	Window Closed / Lapsed

High silicon steel thin strips and a method for producing the same

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