Claims
- 1. A method of producing a grain-oriented electrical steel strip exhibiting superior magnetic properties comprising the steps of heating a slab for a grain-oriented electrical steel strip, which slab contains 0.025 -0.100% C and 2.5 -4.5% Si and, as inhibitor-forming elements, at least one element selected from the group consisting of Al, N, Mn, S, Se, Sb, B, Cu, Bi, Nb, Cr, Sn and Ti, to a temperature not exceeding 1300.degree. C., hot rolling the heated slab to obtain a hot rolled strip, cold rolling the hot rolled strip at a final reduction �ration! ratio of not less than 80% in a single pass or two or more passes with intermediate annealing being performed between passes, subjecting the cold rolled strip to decarburization annealing to impart it with an average primary recrystallization grain diameter d of not less than 15.mu.m and not more than 50.mu.m and a coefficient of primary recrystallization diameter deviation .theta.* of not more than 0.6, nitriding or sulfiding the decarburization-annealed strip after completion of decarburization annealing but not later than the start of secondary recrystallization to increase its AlN or MnS inhibitor strength, and finish annealing the inhibitor-strengthened strip the secondary recrystallization occurring during finish annealing conducted following the decarburization annealing.
Priority Claims (1)
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1-1778 |
Jan 1989 |
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Parent Case Info
This application is a continuation of now abandoned application Ser. No. 08/341,959, filed Nov. 16, 1994 ,which is a continuation of now abandoned application Ser. No. 08/046,901, filed Apr. 15, 1993, which application is a continuation of now abandoned application Ser. No. 07/734,293, filed Jul. 17, 1991, which application is a continuation-in-part of now abandoned application Ser. No. 07/663,205, filed February 28, 1991, which application is a continuation of now abandoned application Ser. No. 07/461,123, filed Jan. 4, 1990.
US Referenced Citations (25)
Foreign Referenced Citations (4)
Number |
Date |
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851066 |
Oct 1960 |
GBX |
943448 |
Dec 1963 |
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1063046 |
Mar 1967 |
GBX |
2101631 |
Jan 1983 |
GBX |
Non-Patent Literature Citations (1)
Entry |
Ushigami, Y., et al., "Influence of Primary Recrystallized Structure on Secondary Recrystallization in Fe-3% Si Alloy", Materials Science Forum, vols 204-206, part 2 (1996), pp. 623-628. |
Continuations (4)
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341959 |
Nov 1994 |
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Parent |
46901 |
Apr 1993 |
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Parent |
734293 |
Jul 1991 |
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Parent |
461123 |
Jan 1990 |
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Continuation in Parts (1)
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663205 |
Feb 1991 |
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