US3925115A - Process employing cooling in a static atmosphere for high permeability silicon steel comprising copper - Google Patents

Process employing cooling in a static atmosphere for high permeability silicon steel comprising copper Download PDF

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Publication number
US3925115A
US3925115A US524831A US52483174A US3925115A US 3925115 A US3925115 A US 3925115A US 524831 A US524831 A US 524831A US 52483174 A US52483174 A US 52483174A US 3925115 A US3925115 A US 3925115A
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US
United States
Prior art keywords
steel
temperature
cooled
improvement according
temperature below
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US524831A
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English (en)
Inventor
James A Salsgiver
Frank A Malagari
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Allegheny Ludlum Corp
Pittsburgh National Bank
Original Assignee
Allegheny Ludlum Industries Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Allegheny Ludlum Industries Inc filed Critical Allegheny Ludlum Industries Inc
Priority to US524831A priority Critical patent/US3925115A/en
Priority to AR261249A priority patent/AR207795A1/es
Priority to MX10011975U priority patent/MX3187E/es
Priority to CA235,669A priority patent/CA1045955A/fr
Priority to AU84946/75A priority patent/AU489122B2/en
Priority to GB38766/75A priority patent/GB1478740A/en
Priority to IT51714/75A priority patent/IT1047746B/it
Priority to ES441709A priority patent/ES441709A1/es
Priority to DE2547313A priority patent/DE2547313C2/de
Priority to FR7532698A priority patent/FR2291275B1/fr
Priority to BE2054633A priority patent/BE834875A/fr
Priority to IN2079/CAL/1975A priority patent/IN143213B/en
Priority to JP50136783A priority patent/JPS5843443B2/ja
Priority to BR7507584*A priority patent/BR7507584A/pt
Priority to YU02912/75A priority patent/YU291275A/xx
Priority to SE7512967A priority patent/SE414948B/xx
Priority to PL1975184806A priority patent/PL106204B1/pl
Application granted granted Critical
Publication of US3925115A publication Critical patent/US3925115A/en
Priority to ZA757206A priority patent/ZA757206B/xx
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
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • C21D8/1266—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 between cold rolling steps
    • 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
    • C21D8/1216—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the working step(s) being of interest
    • C21D8/1233—Cold rolling
    • 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

Definitions

  • the present invention relates to a process for producing electromagnetic silicon steel having a cube-on-edge orientation and a permeability of at least 1850 (6/0 at oersteds.
  • Oriented silicon steels containing 2.60 to 4.0% silicon are generally produced by processes which involve hot rolling, a double cold reduction, an anneal before each cold roll and a high temperature texture anneal. Characterizing these steels are permeabilities at 10 oersteds of from about 1790 to 1840 (6/0,).
  • 357,974 describes a process which includes the steps of: preparing a melt of steel consisting essentially of, by weight, up to 0.07% carbon, from 2.6 to 4.0% silicon, from 0.03 to 0.24% manganese, from 0.01 to 0.07% sulfur, from 0.015 to 0.04% aluminum, up to 0.02% nitrogen, from 0.1 to 0.5% copper, balance iron; casting the steel; hot rolling the steel; annealing the steel prior to a final cold roll at a temperature of from 1400" to 2150F; cooling the steel from a temperature below 1700F and about 750F to a temperature at least as low as 500F with a liquid quenching medium or gaseous stream and from its maximum annealing temperature to the temperature below 1700F and above 750F at a rate which is no faster than one wherein the steel is cooled in a static atmosphere or in a continuous processing line where there is some relative motion between the atmosphere and the steel, although the only deliverate motion is that imparted to the steel; and cold rolling the steel at
  • Described herein is another, and improved method for producing silicon steel having a cube-on-edge orientation and a permeability of at least 1850 (6/0 at 10 oersteds. It is primarily based upon the discovery that the melt of application Ser. No. 357,974 can be prepared with selenium replacing part or all of the sulfur contained therein.
  • the present invention provides a method for producing silicon steel having a cube-on-edge orientation and a permeability of at least 1850 (G/O,,) at 10 oersteds. lnvolved therein are the steps of: preparing a melt of silicon steel consisting essentially of, by weight, up to 0.07% carbon, from 2.60 to 4.0% silicon, from 0.03 to 0.24% manganese, at least 0.01% selenium, from 0.01 to 0.09% of material from the group consisting of sulfur and selenium, from 0.015 to 0.04% aluminum, up to 0.02% nitrogen, from 0.1 to 0.5% copper, balance iron; casting the steel; hot rolling the steel into a hot rolled band; subjecting the steel to at least one cold rolling; subjecting the steel to final annealing prior to the final cold rolling; decarburizing the steel; and final texture annealing the steel. Aslo included, and significantly so,
  • the steel melt must include silicon, aluminum, manganese and selenium. Silicon is necessary as it increases the steels resistivity, decreases its magnetostriction, decreases its magnetocrystalline anisotropy and hence decreases its core loss. Aluminum, manganese and selenium are necessary as they form inhibitors which are essential for controlling the steels orientation and its properties which are dependent thereon. More specifically, aluminum combines with nitrogen in the steel or from the atmosphere, to form aluminum nitride; and manganese combines with selenium, and possibly copper, to form manganese selenide and/or manganese copper selenide, and with sulfur if it is present, to form manganese sulfide and/or manganese copper sulfide.
  • Copper noted above for its presence in manganese inhibitors, can also be beneficial during processing. It is hypothesized that copper can lower the annealing temperature, lower the temperature from which the rapid cool can occur, improve rollability, simplify melting, and relax annealing atmosphere requirements. Moreover, copper increases the steels resistivity and decreases its core loss.
  • a steel in which the process of the present invention is particularly adaptable to consists essentially of, by weight, from 0.02 to 0.0 7% carbon, from 2.65 to 3.25% silicon, from 0.05 to 0.20% manganese, at least 0.02% selenium, from 0.02 to 0.07% of material from the group consisting of sulfur and selenium, from 0.015 to 0.04% aluminum, from 0.0030 to 0.0090% nitrogen, from 0.1 to 0.4% copper, balance iron.
  • This steel has its chemistry balanced so as to produce a highly beneficial structure when processed according to the present invention.
  • inhibitors are aluminum nitride
  • compounds of said steel is cooled from a temperature below 1600F manganese selenide and possibly manganese sulfide. and above 1000F to a temperature at least as low as No criticality is placed upon the particular annealing 500F with a liquid quenching medium or gaseous atmosphere.
  • Illustrative atmosphere therefore include stream and from its maximum annealing temperature nitrogen; reducing gases such as hydrogen; inert gases to said temperature below 1600F and above l000F at such as argon; air; and mixtures thereof.
  • Processing for the heat involved soaking at an elevated temperature for several hours, hot rolling to a gage of said final anneal prior to the final cold rolling is at a approximately 93 mils, heat treating for 1 minute at temperature of from l800 to 2l25F. 2050F, slow cooling to l740F (approximately 50 sec- 4.
  • cess includes the steps of: preparing a melt of silicon said steel is air cooled to said temperature below steel; casting said steel; hot rolling said steel into a hot l700F and above 750F. rolled band; subjecting said steel to at least one cold 8.
  • 500F with a liquid quenching medium or gaseous said steel is air cooled to said temperature below stream and from its maximum annealing temperature l700F and above 750F.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Thermal Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Electromagnetism (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing Of Steel Electrode Plates (AREA)
  • Soft Magnetic Materials (AREA)
  • Metal Rolling (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Heat Treatment Of Steel (AREA)
US524831A 1974-11-18 1974-11-18 Process employing cooling in a static atmosphere for high permeability silicon steel comprising copper Expired - Lifetime US3925115A (en)

Priority Applications (18)

Application Number Priority Date Filing Date Title
US524831A US3925115A (en) 1974-11-18 1974-11-18 Process employing cooling in a static atmosphere for high permeability silicon steel comprising copper
AR261249A AR207795A1 (es) 1974-11-18 1975-01-01 Procedimiento para producir acero de silicio electromagnetico
MX10011975U MX3187E (es) 1974-11-18 1975-09-08 Mejoras en procedimiento para producir acero al siquemador de combustible mejorado para quemar un colicio electromagnetico mbustible liquido gasificable
CA235,669A CA1045955A (fr) 1974-11-18 1975-09-17 Traitement de l'acier haute permeabilite au silice
AU84946/75A AU489122B2 (en) 1974-11-18 1975-09-18 T. processing for high permeability silicon steel
GB38766/75A GB1478740A (en) 1974-11-18 1975-09-22 Processing for high permeability silicon steel
IT51714/75A IT1047746B (it) 1974-11-18 1975-10-09 Perfezionamento nei procedimenti di produzione di acciaio al silicio di elevata permeabilita
ES441709A ES441709A1 (es) 1974-11-18 1975-10-10 Procedimiento mejorado de produccion de acero silicico elec-tromagnetico de elevada permeabilidad.
DE2547313A DE2547313C2 (de) 1974-11-18 1975-10-22 Verfahren zur Herstellung von Elektroblechen mit Goss-Textur
FR7532698A FR2291275B1 (fr) 1974-11-18 1975-10-24 Traitement pour l'obtention d'aciers au silicium a grande permeabilite
BE2054633A BE834875A (fr) 1974-11-18 1975-10-27 Traitement pour l'obtention d'aciers au silicium a grande permeabilite
IN2079/CAL/1975A IN143213B (fr) 1974-11-18 1975-10-29
JP50136783A JPS5843443B2 (ja) 1974-11-18 1975-11-13 デンジケイソコウノセイゾウホウホウ
YU02912/75A YU291275A (en) 1974-11-18 1975-11-17 Process for producing electromagnetic silicon steel
BR7507584*A BR7507584A (pt) 1974-11-18 1975-11-17 Processo para a producao de acosilicio eletromagnetico
PL1975184806A PL106204B1 (pl) 1974-11-18 1975-11-18 Sposob wytwarzania stali krzemowej o teksturze gossa
SE7512967A SE414948B (sv) 1974-11-18 1975-11-18 Forfarande for framstellning av elektromagnetkiselstal med kub-pa-kantorientering
ZA757206A ZA757206B (en) 1974-11-18 1976-09-28 Producing electromagnetic silicon steel

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US524831A US3925115A (en) 1974-11-18 1974-11-18 Process employing cooling in a static atmosphere for high permeability silicon steel comprising copper

Publications (1)

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US3925115A true US3925115A (en) 1975-12-09

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US524831A Expired - Lifetime US3925115A (en) 1974-11-18 1974-11-18 Process employing cooling in a static atmosphere for high permeability silicon steel comprising copper

Country Status (16)

Country Link
US (1) US3925115A (fr)
JP (1) JPS5843443B2 (fr)
AR (1) AR207795A1 (fr)
BE (1) BE834875A (fr)
BR (1) BR7507584A (fr)
CA (1) CA1045955A (fr)
DE (1) DE2547313C2 (fr)
ES (1) ES441709A1 (fr)
FR (1) FR2291275B1 (fr)
GB (1) GB1478740A (fr)
IN (1) IN143213B (fr)
IT (1) IT1047746B (fr)
PL (1) PL106204B1 (fr)
SE (1) SE414948B (fr)
YU (1) YU291275A (fr)
ZA (1) ZA757206B (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0089195A1 (fr) * 1982-03-15 1983-09-21 Kawasaki Steel Corporation Procédé de fabrication de tôles d'acier au silicium à grains orientés et présentant des propriétés magnétiques excellentes
EP0101321A2 (fr) * 1982-08-18 1984-02-22 Kawasaki Steel Corporation Procédé pour la production de tôle ou de bande en acier au silicium à grain orienté présentant une haute induction magnétique et faible perte dans le fer

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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
US4054470A (en) * 1976-06-17 1977-10-18 Allegheny Ludlum Industries, Inc. Boron and copper bearing silicon steel and processing therefore
JPS5948935B2 (ja) * 1981-08-05 1984-11-29 新日本製鐵株式会社 低鉄損一方向性電磁鋼板の製造方法

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3287184A (en) * 1963-10-22 1966-11-22 Bethlehem Steel Corp Method of producing low carbon electrical sheet steel
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
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
US3855020A (en) * 1973-05-07 1974-12-17 Allegheny Ludlum Ind Inc Processing for high permeability silicon steel comprising copper
US3855019A (en) * 1973-05-07 1974-12-17 Allegheny Ludlum Ind Inc Processing for high permeability silicon steel comprising copper
US3855018A (en) * 1972-09-28 1974-12-17 Allegheny Ludlum Ind Inc Method for producing grain oriented silicon steel comprising copper
US3855021A (en) * 1973-05-07 1974-12-17 Allegheny Ludlum Ind Inc Processing for high permeability silicon steel comprising copper

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3873381A (en) * 1973-03-01 1975-03-25 Armco Steel Corp High permeability cube-on-edge oriented silicon steel and method of making it

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3287184A (en) * 1963-10-22 1966-11-22 Bethlehem Steel Corp Method of producing low carbon electrical sheet steel
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
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
US3855018A (en) * 1972-09-28 1974-12-17 Allegheny Ludlum Ind Inc Method for producing grain oriented silicon steel comprising copper
US3855018B1 (fr) * 1972-09-28 1994-02-18 Allegheny Ludlum Corp.
US3855020A (en) * 1973-05-07 1974-12-17 Allegheny Ludlum Ind Inc Processing for high permeability silicon steel comprising copper
US3855019A (en) * 1973-05-07 1974-12-17 Allegheny Ludlum Ind Inc Processing for high permeability silicon steel comprising copper
US3855021A (en) * 1973-05-07 1974-12-17 Allegheny Ludlum Ind Inc Processing for high permeability silicon steel comprising copper

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0089195A1 (fr) * 1982-03-15 1983-09-21 Kawasaki Steel Corporation Procédé de fabrication de tôles d'acier au silicium à grains orientés et présentant des propriétés magnétiques excellentes
EP0101321A2 (fr) * 1982-08-18 1984-02-22 Kawasaki Steel Corporation Procédé pour la production de tôle ou de bande en acier au silicium à grain orienté présentant une haute induction magnétique et faible perte dans le fer
EP0101321A3 (en) * 1982-08-18 1985-11-06 Kawasaki Steel Corporation Method of producing grain oriented silicon steel sheets or strips having high magnetic induction and low iron loss

Also Published As

Publication number Publication date
IT1047746B (it) 1980-10-20
SE7512967L (sv) 1976-05-19
ZA757206B (en) 1976-11-24
GB1478740A (en) 1977-07-06
BE834875A (fr) 1976-02-16
DE2547313A1 (de) 1976-05-20
SE414948B (sv) 1980-08-25
JPS5843443B2 (ja) 1983-09-27
YU291275A (en) 1982-02-28
CA1045955A (fr) 1979-01-09
DE2547313C2 (de) 1986-07-03
FR2291275A1 (fr) 1976-06-11
ES441709A1 (es) 1977-03-16
AR207795A1 (es) 1976-10-29
IN143213B (fr) 1977-10-15
JPS5173921A (fr) 1976-06-26
AU8494675A (en) 1977-03-24
FR2291275B1 (fr) 1985-10-31
PL106204B1 (pl) 1979-12-31
BR7507584A (pt) 1976-08-03

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