US3855018A - Method for producing grain oriented silicon steel comprising copper - Google Patents

Method for producing grain oriented silicon steel comprising copper Download PDF

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Publication number
US3855018A
US3855018A US00357969A US35796973A US3855018A US 3855018 A US3855018 A US 3855018A US 00357969 A US00357969 A US 00357969A US 35796973 A US35796973 A US 35796973A US 3855018 A US3855018 A US 3855018A
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United States
Prior art keywords
steel
hot rolled
rolled band
sulfur
improvement according
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Expired - Lifetime
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US00357969A
Inventor
S Ames
J Salsgiver
G Houze
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Allegheny Ludlum Corp
Pittsburgh National Bank
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Allegheny Ludlum Industries Inc
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=26967808&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=US3855018(A) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Allegheny Ludlum Industries Inc filed Critical Allegheny Ludlum Industries Inc
Priority to US00357969A priority Critical patent/US3855018A/en
Priority to AU60064/73A priority patent/AU472237B2/en
Priority to NL7312694A priority patent/NL7312694A/xx
Priority to FR7333489A priority patent/FR2201342B1/fr
Priority to AT823373A priority patent/AT338311B/en
Priority to DE2348249A priority patent/DE2348249C2/en
Priority to IT52796/73A priority patent/IT996214B/en
Priority to GB4532273A priority patent/GB1415415A/en
Priority to JP48108590A priority patent/JPS5745818B2/ja
Priority to CA182,379A priority patent/CA1003731A/en
Priority to AR250288A priority patent/AR199921A1/en
Priority to PL1973165492A priority patent/PL91102B1/pl
Priority to ES419147A priority patent/ES419147A1/en
Priority to HUAE393A priority patent/HU167081B/hu
Priority to RO7376191A priority patent/RO68034A/en
Priority to SE7313271A priority patent/SE410198B/en
Publication of US3855018A publication Critical patent/US3855018A/en
Application granted granted Critical
Assigned to ALLEGHENY LUDLUM CORPORATION reassignment ALLEGHENY LUDLUM CORPORATION CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). 8-4-86 Assignors: ALLEGHENY LUDLUM STEEL CORPORATION
Assigned to PITTSBURGH NATIONAL BANK reassignment PITTSBURGH NATIONAL BANK SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ALLEGHENY LUDLUM CORPORATION
Assigned to PITTSBURGH NATIONAL BANK reassignment PITTSBURGH NATIONAL BANK ASSIGNMENT OF ASSIGNORS INTEREST. RECORDED ON REEL 4855 FRAME 0400 Assignors: PITTSBURGH NATIONAL BANK
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Publication of US3855018B1 publication Critical patent/US3855018B1/en
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1244—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the heat treatment(s) being of interest
    • C21D8/1261—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the heat treatment(s) being of interest following hot rolling

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Electromagnetism (AREA)
  • Manufacturing Of Steel Electrode Plates (AREA)
  • Soft Magnetic Materials (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Metal Rolling (AREA)

Abstract

Silicon steel alloy melt composition and method for forming grain oriented silicon steel sheets therefrom, characterized in that the resulting sheets have a cube-on-edge texture with permeabilities at 10 oersteds as high as or higher than 1850. The alloy from which the steel is formed preferably contains silicon, sulfur, aluminum, manganese, nitrogen and copper. Maximum permeability is obtained when the steel being processed has a ratio (by weight) of manganese equivalent to sulfur of greater than 2.0 and less than 4.75. It is essential to provide both nitride and sulfide formers which act as primary grain growth inhibitors in a duplex primary grain growth inhibition system to effect the desirable results of the invention.

Claims (5)

1. IN A PROCESS FOR PRODUCING ORIENTED SILICON STEEL INCLUDING THE STEP OF PREPARING A MELT OF STEEL AND CASTING SAME INTO INGOTS, HOT ROLLING SAID INGOTS TO HOT ROLLED BAND GUAGE AN D SUBSEQENTLY COLD ROLLING AND ANNEALING, AS DESIRED TO PRODUCE SILICON STEEL WITH CUBE-ON-EDGE ORIENTATION, THE IMPROVEMENT WHICH COMPRISES PREPARING A MELT OF STEEL HAVING A COMPOSITION CONSISTING ESSENTIALLY OF: CARBON .02 - .07% MANGANESE EQUIVALENT .05 - .24% (%MN + (0.1 TO 0.25) + %CU) SULFUR .01 - .50% SILICON 2.5 - 3.5% ALUMINUM 0.15 - .04% NITROGEN +-90 PARTS PER MILLION COPPER 0.1 TO 0.3% IRON BALANCE AND WHEREIN THE RATIO OF MANGANESE EQUIVALENT TO SULFUR, BY WEIGHT, IS IN THE RANGE OF 2.0 TO 4.75, AND THEREAFTER PROCESSING SAID STEEL TO PRODUCE GRAIN ORIENTED STEEL WITH CUBE-ON-EDGE TEXTURE WHEREBY SAID ORIENTED STEEL HAS A PERMEABILITY OF AT LEAST 1850 AT 10 OERSTEDS DUE TO A DUPLEX SULFIDE AND NITRIDE PRIMARY GRAIN GROWTH INHIBITION SYSTEM, SAID SYSTEM RESULTING FROM THE AFOREMENTIONED CHEMISTRY OF THE STEEL PROCESSED; SAID PROCESSING INCLUDING THE STEP OF SUBJECTING SAID HOT ROLLED BAND TO A TEMPERATURE ABOVE 1400*F FOR 10 SECONDS TO 30 MINUTES, SAID HOT ROLLED BAND HEAT TREATMENT CONTRIBUTING TO THE ATTAINMENT OF SAID HIGH PERMEABILITY FOR SAID ORIENTED SILICON STEEEL
2. An improvement according to claim 1, wherein the ratio of manganese equivalent to sulfur is 2.5 to 4.
3. An improvement according to claim 1 wherein said hot rolled band is heated to 1400*F to 2100*F.
4. An improvement according to claim 1 wherein said hot rolled band is heated to 1650*F to 1850*F.
5. An improvement according to claim 4 wherein said hot rolled band is heated to 1650*F to 1850*F for 10 seconds to 5 minutes.
US00357969A 1972-09-28 1973-05-07 Method for producing grain oriented silicon steel comprising copper Expired - Lifetime US3855018A (en)

Priority Applications (16)

Application Number Priority Date Filing Date Title
US00357969A US3855018A (en) 1972-09-28 1973-05-07 Method for producing grain oriented silicon steel comprising copper
AU60064/73A AU472237B2 (en) 1972-09-28 1973-09-06 Grain oriented silicon steel and method for its production
NL7312694A NL7312694A (en) 1972-09-28 1973-09-14
FR7333489A FR2201342B1 (en) 1972-09-28 1973-09-18
AT823373A AT338311B (en) 1972-09-28 1973-09-25 PROCESS FOR PRODUCING GRAIN ORIENTED SILICONE STEELS
DE2348249A DE2348249C2 (en) 1972-09-28 1973-09-25 Method of manufacturing silicon steel sheet with Goss texture
IT52796/73A IT996214B (en) 1972-09-28 1973-09-27 IMPROVEMENT IN THE PROCESS FOR THE PRODUCTION OF ORIENTED SILICON STEEL
GB4532273A GB1415415A (en) 1972-09-28 1973-09-27 Silicon steel and method for its production
AR250288A AR199921A1 (en) 1972-09-28 1973-09-28 IMPROVED SILICON STEEL AND A PROCEDURE FOR PRODUCING ORIENTED SILICON STEEL THROUGH SUCH IMPROVED SILICON STEEL
SE7313271A SE410198B (en) 1972-09-28 1973-09-28 PROCEDURE FOR PRODUCTION OF ORIENTATED SILK STEEL WITH CUB-PA-EDGE TEXTURE ORIENTATION
JP48108590A JPS5745818B2 (en) 1972-09-28 1973-09-28
PL1973165492A PL91102B1 (en) 1972-09-28 1973-09-28
ES419147A ES419147A1 (en) 1972-09-28 1973-09-28 Method for producing grain oriented silicon steel comprising copper
HUAE393A HU167081B (en) 1972-09-28 1973-09-28
RO7376191A RO68034A (en) 1972-09-28 1973-09-28 SILICON STEEL FOR ELECTROTECHNIC AND METHOD FOR PRODUCING THE SAME
CA182,379A CA1003731A (en) 1972-09-28 1973-09-28 Grain oriented silicon steel and method for its production

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US29319472A 1972-09-28 1972-09-28
US00357969A US3855018A (en) 1972-09-28 1973-05-07 Method for producing grain oriented silicon steel comprising copper

Publications (2)

Publication Number Publication Date
US3855018A true US3855018A (en) 1974-12-17
US3855018B1 US3855018B1 (en) 1994-02-18

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ID=26967808

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US00357969A Expired - Lifetime US3855018A (en) 1972-09-28 1973-05-07 Method for producing grain oriented silicon steel comprising copper

Country Status (16)

Country Link
US (1) US3855018A (en)
JP (1) JPS5745818B2 (en)
AR (1) AR199921A1 (en)
AT (1) AT338311B (en)
AU (1) AU472237B2 (en)
CA (1) CA1003731A (en)
DE (1) DE2348249C2 (en)
ES (1) ES419147A1 (en)
FR (1) FR2201342B1 (en)
GB (1) GB1415415A (en)
HU (1) HU167081B (en)
IT (1) IT996214B (en)
NL (1) NL7312694A (en)
PL (1) PL91102B1 (en)
RO (1) RO68034A (en)
SE (1) SE410198B (en)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3925115A (en) * 1974-11-18 1975-12-09 Allegheny Ludlum Ind Inc Process employing cooling in a static atmosphere for high permeability silicon steel comprising copper
US3929522A (en) * 1974-11-18 1975-12-30 Allegheny Ludlum Ind Inc Process involving cooling in a static atmosphere for high permeability silicon steel comprising copper
US3940299A (en) * 1973-10-31 1976-02-24 Kawasaki Steel Corporation Method for producing single-oriented electrical steel sheets having a high magnetic induction
US4010050A (en) * 1975-09-08 1977-03-01 Allegheny Ludlum Industries, Inc. Processing for aluminum nitride inhibited oriented silicon steel
US4078952A (en) * 1976-06-17 1978-03-14 Allegheny Ludlum Industries, Inc. Controlling the manganese to sulfur ratio during the processing for high permeability silicon steel
US4171994A (en) * 1975-02-13 1979-10-23 Allegheny Ludlum Industries, Inc. Use of nitrogen-bearing base coatings in the manufacture of high permeability silicon steel
US4493739A (en) * 1981-08-05 1985-01-15 Nippon Steel Corporation Process for producing a grain-oriented electromagnetic steel sheet or strip having a low watt loss and a grain-oriented electromagnetic steel strip having uniform magnetic properties
US4753692A (en) * 1981-08-05 1988-06-28 Nippon Steel Corporation Grain-oriented electromagnetic steel sheet and process for producing the same
US5401332A (en) * 1991-07-12 1995-03-28 Pohang Iron & Steel Co., Ltd. Grain oriented electrical steel sheet having superior magnetic properties, and manufacturing process thereof
AU673720B2 (en) * 1993-04-05 1996-11-21 Thyssen Stahl Aktiengesellschaft Process for the production of grain oriented magnetic steel sheets having improved remagnetization losses

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE8107844L (en) * 1981-03-19 1982-09-20 Allegheny Ludlum Steel SET TO MAKE CORNORIENTED SILICONE
KR940003339B1 (en) * 1991-12-26 1994-04-20 포항종합제철 주식회사 Magnetic materials
EP0709470B1 (en) * 1993-11-09 2001-10-04 Pohang Iron & Steel Co., Ltd. Production method of directional electromagnetic steel sheet of low temperature slab heating system
FR2731713B1 (en) * 1995-03-14 1997-04-11 Ugine Sa PROCESS FOR THE MANUFACTURE OF A SHEET OF ELECTRIC STEEL WITH ORIENTED GRAINS FOR THE PRODUCTION OF MAGNETIC TRANSFORMER CIRCUITS IN PARTICULAR
DE19745445C1 (en) * 1997-10-15 1999-07-08 Thyssenkrupp Stahl Ag Process for the production of grain-oriented electrical sheet with low magnetic loss and high polarization
CN107794439B (en) * 2016-08-30 2019-04-23 宝山钢铁股份有限公司 Extra-low iron loss non-oriented electromagnetic steel sheet and its manufacturing method
CN109554525B (en) * 2018-12-03 2020-12-15 武汉钢铁有限公司 Manufacturing method of mirror-surface oriented silicon steel

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2867558A (en) * 1956-12-31 1959-01-06 Gen Electric Method for producing grain-oriented silicon steel
US3159511A (en) * 1956-11-08 1964-12-01 Yawata Iron & Steel Co Process of producing single-oriented silicon steel
US3266955A (en) * 1962-12-28 1966-08-16 Yawata Iron & Steel Co Process for producing silicon steel sheet having (100) plane in the rolling plane
US3287183A (en) * 1964-06-22 1966-11-22 Yawata Iron & Steel Co Process for producing single-oriented silicon steel sheets having a high magnetic induction
US3575739A (en) * 1968-11-01 1971-04-20 Gen Electric Secondary recrystallization of silicon iron with nitrogen
US3632456A (en) * 1968-04-27 1972-01-04 Nippon Steel Corp Method for producing an electromagnetic steel sheet of a thin sheet thickness having a high-magnetic induction
US3671337A (en) * 1969-02-21 1972-06-20 Nippon Steel Corp Process for producing grain oriented electromagnetic steel sheets having excellent magnetic characteristics
US3700506A (en) * 1968-12-10 1972-10-24 Nippon Steel Corp Method for reducing an iron loss of an oriented magnetic steel sheet having a high magnetic induction
US3764406A (en) * 1971-11-04 1973-10-09 Armco Steel Corp Hot working method of producing cubeon edge oriented silicon iron from cast slabs
US3770517A (en) * 1972-03-06 1973-11-06 Allegheny Ludlum Ind Inc Method of producing substantially non-oriented silicon steel strip by three-stage cold rolling

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2173312A (en) * 1937-08-14 1939-09-19 Heraeus Vacuumschmelze Ag Silicon-iron alloy
DE1117624B (en) * 1958-08-13 1961-11-23 Allegheny Ludlum Steel Process for the production of strips with a high grain orientation from an iron-silicon alloy
US3144363A (en) * 1961-12-14 1964-08-11 Westinghouse Electric Corp Process for producing oriented silicon steel and the product thereof
US3438820A (en) * 1965-04-02 1969-04-15 Dominion Foundries & Steel Silicon steel process
US3636579A (en) * 1968-04-24 1972-01-25 Nippon Steel Corp Process for heat-treating electromagnetic steel sheets having a high magnetic induction
AT362973B (en) * 1979-08-06 1981-06-25 List Hans ELEMENT FOR SEALING THE SEPARATOR BETWEEN TWO PARTS ENCLOSING A GASKET

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3159511A (en) * 1956-11-08 1964-12-01 Yawata Iron & Steel Co Process of producing single-oriented silicon steel
US2867558A (en) * 1956-12-31 1959-01-06 Gen Electric Method for producing grain-oriented silicon steel
US3266955A (en) * 1962-12-28 1966-08-16 Yawata Iron & Steel Co Process for producing silicon steel sheet having (100) plane in the rolling plane
US3287183A (en) * 1964-06-22 1966-11-22 Yawata Iron & Steel Co Process for producing single-oriented silicon steel sheets having a high magnetic induction
US3632456A (en) * 1968-04-27 1972-01-04 Nippon Steel Corp Method for producing an electromagnetic steel sheet of a thin sheet thickness having a high-magnetic induction
US3575739A (en) * 1968-11-01 1971-04-20 Gen Electric Secondary recrystallization of silicon iron with nitrogen
US3700506A (en) * 1968-12-10 1972-10-24 Nippon Steel Corp Method for reducing an iron loss of an oriented magnetic steel sheet having a high magnetic induction
US3671337A (en) * 1969-02-21 1972-06-20 Nippon Steel Corp Process for producing grain oriented electromagnetic steel sheets having excellent magnetic characteristics
US3764406A (en) * 1971-11-04 1973-10-09 Armco Steel Corp Hot working method of producing cubeon edge oriented silicon iron from cast slabs
US3770517A (en) * 1972-03-06 1973-11-06 Allegheny Ludlum Ind Inc Method of producing substantially non-oriented silicon steel strip by three-stage cold rolling

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Kussmann, A. et al; Gekupferter Stahl For Dynamo-Und Transformaturen Bleche, in Stahl & Eisen, 50, 1930, pp. 1194 1197. *

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3940299A (en) * 1973-10-31 1976-02-24 Kawasaki Steel Corporation Method for producing single-oriented electrical steel sheets having a high magnetic induction
US3925115A (en) * 1974-11-18 1975-12-09 Allegheny Ludlum Ind Inc Process employing cooling in a static atmosphere for high permeability silicon steel comprising copper
US3929522A (en) * 1974-11-18 1975-12-30 Allegheny Ludlum Ind Inc Process involving cooling in a static atmosphere for high permeability silicon steel comprising copper
US4171994A (en) * 1975-02-13 1979-10-23 Allegheny Ludlum Industries, Inc. Use of nitrogen-bearing base coatings in the manufacture of high permeability silicon steel
US4010050A (en) * 1975-09-08 1977-03-01 Allegheny Ludlum Industries, Inc. Processing for aluminum nitride inhibited oriented silicon steel
US4078952A (en) * 1976-06-17 1978-03-14 Allegheny Ludlum Industries, Inc. Controlling the manganese to sulfur ratio during the processing for high permeability silicon steel
US4493739A (en) * 1981-08-05 1985-01-15 Nippon Steel Corporation Process for producing a grain-oriented electromagnetic steel sheet or strip having a low watt loss and a grain-oriented electromagnetic steel strip having uniform magnetic properties
US4753692A (en) * 1981-08-05 1988-06-28 Nippon Steel Corporation Grain-oriented electromagnetic steel sheet and process for producing the same
US4863532A (en) * 1981-08-05 1989-09-05 Nippon Steel Corporation Grain-oriented electromagnetic steel sheet
US5401332A (en) * 1991-07-12 1995-03-28 Pohang Iron & Steel Co., Ltd. Grain oriented electrical steel sheet having superior magnetic properties, and manufacturing process thereof
AU673720B2 (en) * 1993-04-05 1996-11-21 Thyssen Stahl Aktiengesellschaft Process for the production of grain oriented magnetic steel sheets having improved remagnetization losses

Also Published As

Publication number Publication date
PL91102B1 (en) 1977-02-28
ES419147A1 (en) 1976-12-16
JPS5745818B2 (en) 1982-09-30
AU6006473A (en) 1975-03-06
NL7312694A (en) 1974-04-01
SE410198B (en) 1979-10-01
DE2348249A1 (en) 1974-04-04
DE2348249C2 (en) 1983-03-03
IT996214B (en) 1975-12-10
GB1415415A (en) 1975-11-26
RO68034A (en) 1982-02-26
FR2201342B1 (en) 1977-08-12
US3855018B1 (en) 1994-02-18
AR199921A1 (en) 1974-10-08
CA1003731A (en) 1977-01-18
HU167081B (en) 1975-08-28
JPS4972118A (en) 1974-07-12
FR2201342A1 (en) 1974-04-26
ATA823373A (en) 1976-12-15
AT338311B (en) 1977-08-25
AU472237B2 (en) 1976-05-20

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AS Assignment

Owner name: ALLEGHENY LUDLUM CORPORATION

Free format text: CHANGE OF NAME;ASSIGNOR:ALLEGHENY LUDLUM STEEL CORPORATION;REEL/FRAME:004779/0642

Effective date: 19860805

AS Assignment

Owner name: PITTSBURGH NATIONAL BANK

Free format text: SECURITY INTEREST;ASSIGNOR:ALLEGHENY LUDLUM CORPORATION;REEL/FRAME:004855/0400

Effective date: 19861226

AS Assignment

Owner name: PITTSBURGH NATIONAL BANK

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST. RECORDED ON REEL 4855 FRAME 0400;ASSIGNOR:PITTSBURGH NATIONAL BANK;REEL/FRAME:005018/0050

Effective date: 19881129

RR Request for reexamination filed

Effective date: 19900427

B1 Reexamination certificate first reexamination