CA1041879A - Processing for high permeability silicon steel - Google Patents
Processing for high permeability silicon steelInfo
- Publication number
- CA1041879A CA1041879A CA235,675A CA235675A CA1041879A CA 1041879 A CA1041879 A CA 1041879A CA 235675 A CA235675 A CA 235675A CA 1041879 A CA1041879 A CA 1041879A
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- CA
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- Prior art keywords
- steel
- temperature
- process according
- cooled
- final
- 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.)
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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
- 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
- C21D8/1216—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
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Manufacturing & Machinery (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Manufacturing Of Steel Electrode Plates (AREA)
- Soft Magnetic Materials (AREA)
- Heat Treatment Of Sheet Steel (AREA)
- Metal Rolling (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A process for producing silicon steel having a cube-on-edge orientation and a permeability of at least 1850 (G/Oe) at 10 oersteds, which includes the steps of: preparing a melt of 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, from 0.01 to 0.09% of material from the group consist-ing of sulfur and selenium, from 0.015 to 0. 04% aluminum, up to 0.02% nitrogen, from 0.1 to 0.5% copper, from 0.00045 to 0.0035%
boron, 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 2150°F; cooling the steel from a temperature below 1700°F and above 750°F to a temperature at least as low as 500°F with a liquid quenching medium or gaseous stream and from its maximum annealing temperature to the temperature below 1700°F and above 750°F 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 deliber-ate motion is that imparted to the steel; and cold rolling the steel at a reduction of at least 80%.
A process for producing silicon steel having a cube-on-edge orientation and a permeability of at least 1850 (G/Oe) at 10 oersteds, which includes the steps of: preparing a melt of 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, from 0.01 to 0.09% of material from the group consist-ing of sulfur and selenium, from 0.015 to 0. 04% aluminum, up to 0.02% nitrogen, from 0.1 to 0.5% copper, from 0.00045 to 0.0035%
boron, 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 2150°F; cooling the steel from a temperature below 1700°F and above 750°F to a temperature at least as low as 500°F with a liquid quenching medium or gaseous stream and from its maximum annealing temperature to the temperature below 1700°F and above 750°F 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 deliber-ate motion is that imparted to the steel; and cold rolling the steel at a reduction of at least 80%.
Description
~04~9 1 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 (G/Oe) at 10 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 (G/Oe).
- In recent years a number of patents have disclosed methods for producing silicon steels with permeabilities in ~ -excess of 1850 (G/Oe) at 10 oersteds. Of these United States Patent Nos. 3,287,183, 3,632,456 and 3,636,579 appear to be the most interesting. A still more interesting method is, however, 1 described in a United States patent. The patent is U.S. Patent j No. 3,855,020 which issued December 17, 1974 in the names of James A. Salsgiver and Frank A. Malagari. Patent 3,855,020 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 -~
!t a final cold roll at a temperature of from 1400 to 2150F; -.,j , cooling the steel from a temperature below 1700F and above -,~
i 750P to a temperature at least as low as 500F with a liquid f quenching medium or gaseous stream and from its maximum annealing temperature to the temperature below 1700F and above 750F at a rate which i8 no faster than one wherein the stee1 is cooled ,-~, . .
B
,~ .
, .-- , " " ., ,- ~ .. ..
10418~79 1 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 deliberate motion is that imparted to the steel; and cold rolling the steel at a reduction of at least 80%.
Described herein is another, and improved method for producing silicon steel having a cube-on-edge orientation and a i permeability of at least 1850 (G/Oe) at 10 oersteds. It is 3 primarily based upon the discovery that the melts of above mentioned U.S. patent 3,855,020 with another D.S. Patent No.
3,925,115 which issued to the applicant on December 9, 1975 can be prepared with boron added thereto. Boron has been successfully used to help develop high permeability in grain oriented silicon steels. It is primarily based upon the dis-covery that the melt of U.S. Patent 3,855,020 can be prepared with selenium replacing part or all of the sulfur contained therein.
It is accordingly an object of the present invention to provide a process for producing electromagnetic silicon steel having a cube-on-edge orientation and a permeability of at ~. ~ , . .. . .
j least 1850 (G/Oe) at 10 oersteds.
-The present invention provides a method for producing ? silicon steel having a cube-on-edge orientation and a permeability ,...
of at least 1850 (G/Oe) at 10 oersteds. Involved therein are ~ the steps of: preparing a melt of silicon steel consisting j essentially of, by weight, up to 0.07~ carbon, from 2.60 to --~ 4.0~ silicon, from 0.03% to 0.24% manganese, from 0.01 to 0.09 of material from the group consisting of sulfur and selenium, rom 0.015 to 0.04% aluminum, up to 0.02~ nitrogen, from 0.1 - -to 0.5% copper, from 0~00045 to 0.0035% boron, balance iron;
' ' :
~ -2-" ~ ' ,:
: " , . . . .
, ,~, ,: ,,,, ., .,,, . , , . ,., ., ., .; , " :, , . : . :, , 10418~79- 1 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 a final annealing prior to the final cold rolling;
decarburizing the steel; and final texture annealing the steel.
Also included, and significantly so, are the specific steps of:
carrying out the final anneal prior to the final cold rolling at a temperature of from 1400 to 2150F for a period of from 15 seconds to 2 hours; cooling the steel from a temperature below .
1700F and above 750F to a temperatuxe 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 - .
., .
....
- , l ` .
.~ , '.. -'.. ,' ~, `,/~ 20 .~ .. , , . .
.~ . :, . . .
,~ .'.: ' .'.
~' ' ' '''.'', ' --,'.
''' .~ . . ' :',' " ' ~O ~
~ .
~ B
"~ , 1041~79 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 deliberate motion is that imparted to the steel; and cold rolling the cooled steel at a reduction of at least 80%. Preferred conditions include annealing at a temperature of from 1800 to 2125F~ cooling with a liquid quenching medium or gaseous stream from a temperature below 1600F and above 1000F, and cold rolling at a reduction of at least 85%.
Melting, casting, hot rolling, cold rolling, decarburi ing and final texture annealing do not involve any novel procedure, as far as techniques!are 0 concerned, and with regard to them, the invention encompasses all applicable -` steelmaking procedures. As to the cold rolling, it should however, be pointed , out that several roll passes can constitute a single cold rolling operation, and 1 that plural cold rolling operations exist only when cold rolling passes are separated by an anneal.
I5 Jn addition to boron, the steel melt must include silicon, aluminum, - manganese, and sulfur and/or selenium, Silicon is n~ecessary as it increases ~ -the steels' resistivity, decreases itq magnetostriction, decreases its magnetocrystalline anisotropy and hence decreases its aD re loss. Aluminum, - -manganese, and sulfur and/or selenium are necessary as they form inhibitors ~0 wh*h are essential for controlling the steels' orientation and its properties wh~ch ire depende~t thereon. More specifically, aluminum cornbines with n~trogen in the steel or from the atmosphere, to form aluminùm nitride; and mangane~e combines with sulfur and/or selenium, and possibly copper, to form - manganese.sulfide and/or manganese copper sulfide and/or manganese selenide ~25 and!or sn~Lngane~e copper salenide, All together, these compounds Lnhibit normal grain growth during the final texture anneal, while at the same time a~d~ng in the development of ~econdary recrystallized grains having the desired r~
1041~179 cube-on-edge orientation, Copper, noted dbove 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 frorn which the rapid cool can occur, improve rollability, ~implify melting, and relax S annealing atmosphere requirements. Moreover, copper increases the steels' resistivity and decreases its D re loss, A steel in which the process of the present invention is particularly adaptable to consists essentially of, by weight, from 0.02 to 0.07% carbon, from2 . 65 to 3. 2 5~o silicon, fro m 0, 0 5 to 0 . 20 % mangane se, from 0 . 02 to 0 . 07% of ~10 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, from - -0.0005 to 0.0025% boron, balance iron. This steel has its chemistry balanced ~o as to produce a highly beneficial structure when processed according to the present invention. As a general rule boron contents will be in excess of 0. 0007%. -., .
` Although we are not sure why the final a,nneal prior to the final cold --~ rolling, and the controlled cooling of the present invention is so beneficial, we hypothe~ize: that the anneal conditions the steel for cold rollilg and providean operation during which inhibitors car. form; and that the slow cool to a temperature below 1700F and/or the use of annealing temperatures in the lo~er part of the annealing temperature range, increase the uniformity in which the inhibitor3 are distrlbuted, as essentially only ferrite phase i~ -pre~cnt in the steel at temperatures below 1700F, contrasted to the presellce of au~tenite and ferrite phase~ and different solubilitics for the inhibiting , elemeslts in each phase at somewhat higher temperat ures, As discussed above, the prirnary i~hlbitor~ are aluminum nitride, and compounds of manganese ~u14ide and mangane~e selenide, No criticality is placed upon the particular .,j , -- S --" . r~
~041879 anne:~ ing atmosphere. nlustrative atmcspheres therefore include nitrogen;
reducing gases such as hydrogen; inert gases such as argon; air; and mixtures thereof .
The following examples are illustrative of several aspects of the invention.
Four heats of steel were cast and processed into silicon steel having a cube-on-edge orientation. The chemistry of the heats appears hereinbelow in Table L - -TABLE L
. ' ~0 Composition (wt. %) Heat C Mn Si S Al N Cu B Fe , A 0.045 0.11 2.840.0350.0300.0078 0.20.00048Bal. i -~
B 0.046 0.11 2.850,0360,0290.0065 0.20,00078Bal.
C 0.046 0,11 2.830.0350.0300.0062 0.190.00141Bal.
D 0.046 S). ll 2.840.0350.0300.0064 0.20.00226Bal.
. ~ ' '.
Processing for the heats involved soaking at an elevated temperature for ~ -soveral hours, hot rolling to a gage of approximately 93 mils, heat treating for 1 minute at 2050F, slow cooling to 1740F (approximately 50 seconds), air -. cooling to 1100F, water quenching from 1100F, cold rolling to a final gage of ~0 approximately 12 mils, decarburizing at a temperature of 1475F in a mixture 'A;' of wet hydrogen and nitrogen, and final texture annealing at a maximum s ten~perature of 2150 F.
TSe heat~ weré te~tod for permeability. Respective permeabilities - -of 1906, 1889, 1873 and 1898 (G/Oe) at 10 oersteds were recorded.
, . . .
,~ -"~ - 6-.
10418~9 ~ w~ e apparer.t Lo those skilled in the art that the novel principles of the invention disclosed herein in connection with specific exarnples thereof will suggest various other modifications and applications of the same.
It is accordingly desired that in construing the breadth of the appended claims they shall not be limited to the specific examples of the invention described herein, ., ~ , .
i . .
., .
,j ' . , , , , ~ .
, ,
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 (G/Oe).
- In recent years a number of patents have disclosed methods for producing silicon steels with permeabilities in ~ -excess of 1850 (G/Oe) at 10 oersteds. Of these United States Patent Nos. 3,287,183, 3,632,456 and 3,636,579 appear to be the most interesting. A still more interesting method is, however, 1 described in a United States patent. The patent is U.S. Patent j No. 3,855,020 which issued December 17, 1974 in the names of James A. Salsgiver and Frank A. Malagari. Patent 3,855,020 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 -~
!t a final cold roll at a temperature of from 1400 to 2150F; -.,j , cooling the steel from a temperature below 1700F and above -,~
i 750P to a temperature at least as low as 500F with a liquid f quenching medium or gaseous stream and from its maximum annealing temperature to the temperature below 1700F and above 750F at a rate which i8 no faster than one wherein the stee1 is cooled ,-~, . .
B
,~ .
, .-- , " " ., ,- ~ .. ..
10418~79 1 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 deliberate motion is that imparted to the steel; and cold rolling the steel at a reduction of at least 80%.
Described herein is another, and improved method for producing silicon steel having a cube-on-edge orientation and a i permeability of at least 1850 (G/Oe) at 10 oersteds. It is 3 primarily based upon the discovery that the melts of above mentioned U.S. patent 3,855,020 with another D.S. Patent No.
3,925,115 which issued to the applicant on December 9, 1975 can be prepared with boron added thereto. Boron has been successfully used to help develop high permeability in grain oriented silicon steels. It is primarily based upon the dis-covery that the melt of U.S. Patent 3,855,020 can be prepared with selenium replacing part or all of the sulfur contained therein.
It is accordingly an object of the present invention to provide a process for producing electromagnetic silicon steel having a cube-on-edge orientation and a permeability of at ~. ~ , . .. . .
j least 1850 (G/Oe) at 10 oersteds.
-The present invention provides a method for producing ? silicon steel having a cube-on-edge orientation and a permeability ,...
of at least 1850 (G/Oe) at 10 oersteds. Involved therein are ~ the steps of: preparing a melt of silicon steel consisting j essentially of, by weight, up to 0.07~ carbon, from 2.60 to --~ 4.0~ silicon, from 0.03% to 0.24% manganese, from 0.01 to 0.09 of material from the group consisting of sulfur and selenium, rom 0.015 to 0.04% aluminum, up to 0.02~ nitrogen, from 0.1 - -to 0.5% copper, from 0~00045 to 0.0035% boron, balance iron;
' ' :
~ -2-" ~ ' ,:
: " , . . . .
, ,~, ,: ,,,, ., .,,, . , , . ,., ., ., .; , " :, , . : . :, , 10418~79- 1 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 a final annealing prior to the final cold rolling;
decarburizing the steel; and final texture annealing the steel.
Also included, and significantly so, are the specific steps of:
carrying out the final anneal prior to the final cold rolling at a temperature of from 1400 to 2150F for a period of from 15 seconds to 2 hours; cooling the steel from a temperature below .
1700F and above 750F to a temperatuxe 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 - .
., .
....
- , l ` .
.~ , '.. -'.. ,' ~, `,/~ 20 .~ .. , , . .
.~ . :, . . .
,~ .'.: ' .'.
~' ' ' '''.'', ' --,'.
''' .~ . . ' :',' " ' ~O ~
~ .
~ B
"~ , 1041~79 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 deliberate motion is that imparted to the steel; and cold rolling the cooled steel at a reduction of at least 80%. Preferred conditions include annealing at a temperature of from 1800 to 2125F~ cooling with a liquid quenching medium or gaseous stream from a temperature below 1600F and above 1000F, and cold rolling at a reduction of at least 85%.
Melting, casting, hot rolling, cold rolling, decarburi ing and final texture annealing do not involve any novel procedure, as far as techniques!are 0 concerned, and with regard to them, the invention encompasses all applicable -` steelmaking procedures. As to the cold rolling, it should however, be pointed , out that several roll passes can constitute a single cold rolling operation, and 1 that plural cold rolling operations exist only when cold rolling passes are separated by an anneal.
I5 Jn addition to boron, the steel melt must include silicon, aluminum, - manganese, and sulfur and/or selenium, Silicon is n~ecessary as it increases ~ -the steels' resistivity, decreases itq magnetostriction, decreases its magnetocrystalline anisotropy and hence decreases its aD re loss. Aluminum, - -manganese, and sulfur and/or selenium are necessary as they form inhibitors ~0 wh*h are essential for controlling the steels' orientation and its properties wh~ch ire depende~t thereon. More specifically, aluminum cornbines with n~trogen in the steel or from the atmosphere, to form aluminùm nitride; and mangane~e combines with sulfur and/or selenium, and possibly copper, to form - manganese.sulfide and/or manganese copper sulfide and/or manganese selenide ~25 and!or sn~Lngane~e copper salenide, All together, these compounds Lnhibit normal grain growth during the final texture anneal, while at the same time a~d~ng in the development of ~econdary recrystallized grains having the desired r~
1041~179 cube-on-edge orientation, Copper, noted dbove 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 frorn which the rapid cool can occur, improve rollability, ~implify melting, and relax S annealing atmosphere requirements. Moreover, copper increases the steels' resistivity and decreases its D re loss, A steel in which the process of the present invention is particularly adaptable to consists essentially of, by weight, from 0.02 to 0.07% carbon, from2 . 65 to 3. 2 5~o silicon, fro m 0, 0 5 to 0 . 20 % mangane se, from 0 . 02 to 0 . 07% of ~10 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, from - -0.0005 to 0.0025% boron, balance iron. This steel has its chemistry balanced ~o as to produce a highly beneficial structure when processed according to the present invention. As a general rule boron contents will be in excess of 0. 0007%. -., .
` Although we are not sure why the final a,nneal prior to the final cold --~ rolling, and the controlled cooling of the present invention is so beneficial, we hypothe~ize: that the anneal conditions the steel for cold rollilg and providean operation during which inhibitors car. form; and that the slow cool to a temperature below 1700F and/or the use of annealing temperatures in the lo~er part of the annealing temperature range, increase the uniformity in which the inhibitor3 are distrlbuted, as essentially only ferrite phase i~ -pre~cnt in the steel at temperatures below 1700F, contrasted to the presellce of au~tenite and ferrite phase~ and different solubilitics for the inhibiting , elemeslts in each phase at somewhat higher temperat ures, As discussed above, the prirnary i~hlbitor~ are aluminum nitride, and compounds of manganese ~u14ide and mangane~e selenide, No criticality is placed upon the particular .,j , -- S --" . r~
~041879 anne:~ ing atmosphere. nlustrative atmcspheres therefore include nitrogen;
reducing gases such as hydrogen; inert gases such as argon; air; and mixtures thereof .
The following examples are illustrative of several aspects of the invention.
Four heats of steel were cast and processed into silicon steel having a cube-on-edge orientation. The chemistry of the heats appears hereinbelow in Table L - -TABLE L
. ' ~0 Composition (wt. %) Heat C Mn Si S Al N Cu B Fe , A 0.045 0.11 2.840.0350.0300.0078 0.20.00048Bal. i -~
B 0.046 0.11 2.850,0360,0290.0065 0.20,00078Bal.
C 0.046 0,11 2.830.0350.0300.0062 0.190.00141Bal.
D 0.046 S). ll 2.840.0350.0300.0064 0.20.00226Bal.
. ~ ' '.
Processing for the heats involved soaking at an elevated temperature for ~ -soveral hours, hot rolling to a gage of approximately 93 mils, heat treating for 1 minute at 2050F, slow cooling to 1740F (approximately 50 seconds), air -. cooling to 1100F, water quenching from 1100F, cold rolling to a final gage of ~0 approximately 12 mils, decarburizing at a temperature of 1475F in a mixture 'A;' of wet hydrogen and nitrogen, and final texture annealing at a maximum s ten~perature of 2150 F.
TSe heat~ weré te~tod for permeability. Respective permeabilities - -of 1906, 1889, 1873 and 1898 (G/Oe) at 10 oersteds were recorded.
, . . .
,~ -"~ - 6-.
10418~9 ~ w~ e apparer.t Lo those skilled in the art that the novel principles of the invention disclosed herein in connection with specific exarnples thereof will suggest various other modifications and applications of the same.
It is accordingly desired that in construing the breadth of the appended claims they shall not be limited to the specific examples of the invention described herein, ., ~ , .
i . .
., .
,j ' . , , , , ~ .
, ,
Claims (16)
1. In a process for producing electromagnetic silicon steel having a cube-on-edge orientation and a permeability of at least 1850 (G/Oe) at 10 oersteds, which process includes the steps of: preparing a melt of silicone steel; casting said steel; hot rolling said steel into a hot rolled band; subjecting said steel to at least one cold rolling; subjecting said steel to a final annealing prior to the final cold rolling; decarbur-izing said steel; and final texture annealing said steel; the improvement comprising the steps of carrying out said final anneal prior to the final cold rolling at a temperature of from 1400 to 2150°F for a period of from 15 seconds to 2 hours;
cooling said steel from a temperature below 1700°F and above 750°F to a temperature at least as low as 500°F with a liquid quenching medium or gaseous stream and from its maximum annealing temperature to said temperature below 1700°F and about 750°F
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 deliberate motion is that imparted to the steel; and cold rolling the cooled steel at a reduction of at least 80%; said melt consisting essentially of, by weight, up to 0.07% carbon, from 2.60 to 4.0% silicon, from 0.03 to 0.24% manganese, from 0.01 to 0.09% of material from the group consisting of sulfur and selenium, from 0.015 to 0Ø4%
aluminum, up to 0.02% nitrogen, from 0.1 to 0.5% copper, from 0.00045 to 0.0035% boron, balance iron.
2. A process according to claim 1, wherein said steel is cooled from a temperature below 1600°F and above 1000°F to a temperature at least as low as 500°F with a liquid quenching medium or gaseous stream and from its maximum annealing tempera-ture to said temperature below 1600°F and above 1000°F at a
cooling said steel from a temperature below 1700°F and above 750°F to a temperature at least as low as 500°F with a liquid quenching medium or gaseous stream and from its maximum annealing temperature to said temperature below 1700°F and about 750°F
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 deliberate motion is that imparted to the steel; and cold rolling the cooled steel at a reduction of at least 80%; said melt consisting essentially of, by weight, up to 0.07% carbon, from 2.60 to 4.0% silicon, from 0.03 to 0.24% manganese, from 0.01 to 0.09% of material from the group consisting of sulfur and selenium, from 0.015 to 0Ø4%
aluminum, up to 0.02% nitrogen, from 0.1 to 0.5% copper, from 0.00045 to 0.0035% boron, balance iron.
2. A process according to claim 1, wherein said steel is cooled from a temperature below 1600°F and above 1000°F to a temperature at least as low as 500°F with a liquid quenching medium or gaseous stream and from its maximum annealing tempera-ture to said temperature below 1600°F and above 1000°F at a
Claim 2 cont'd.
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 deliberate motion is that imparted to the steel.
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 deliberate motion is that imparted to the steel.
3. A process according to claim 1, wherein said final anneal prior to the final cold rolling is at a temperature from 1800 to 2125°F.
4. A process according to claim 3, wherein said steel is cooled from a temperature below 1600°F and above 1000°F to a temperature at least as low as 500°F with a liquid quenching medium or gaseous stream and from its maximum annealing temperature to said temperature below 1600°F and above 1000°F
at a rate which is no faster then 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 deliberate motion is that imparted to the steel.
at a rate which is no faster then 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 deliberate motion is that imparted to the steel.
5. A process according to claim 1, wherein said steel is cooled to a temperature at least as low as 500°F from a tempera-ture below 1700°F and above 750°F with a gaseous stream.
6. A process according to claim 1, wherein said steel is cooled to a temperature at least as low as 500°F from a tempera-ture below 1700°F and above 750°F with a liquid quenching medium.
7. A process according to claim 1, wherein said steel is air cooled to said temperature below 1700°F and above 750°F.
8. A process according to claim 3, wherein said steel is cooled to a temperature at least as low as 500°F from a tempera-ture below 1700°F and above 750°F with a gaseous stream.
9. A process according to claim 3, wherein said steel is cooled to a temperature at least as low as 500°F from a tempera-ture below 1700°F and above 750°F with a liquid quenching medium.
10. A process according to claim 3, wherein said steel is air cooled to said temperature below 1700°F and above 750°F.
11. A process according to claim 1, wherein said final anneal prior to the final cold rolling is carried out subsequent to an initial cold rolling.
12. A process according to claim 1, wherein said steel consists essentially of, by weight, from 0.02 to 0.07% carbon, from 2.65 to 3.25% silicon, from 0.05 to 0.20% manganese, from 0.02 to 0.09% 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, from 0.0005 to 0.0025%
boron, balance iron.
boron, balance iron.
13. A process according to claim 12, wherein said steel has at least 0.0007% boron.
14. A process according to claim 1, wherein the cooled steel is cold rolled at a reduction of at least 85%.
15. A process according to claim 3, wherein the cooled steel is cold rolled at a reduction of at least 85%.
16. A process according to claim 1, wherein said final anneal prior to the final cold rolling is applied to a hot rolled band.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US524846A US3929522A (en) | 1974-11-18 | 1974-11-18 | Process involving cooling in a static atmosphere for high permeability silicon steel comprising copper |
Publications (1)
Publication Number | Publication Date |
---|---|
CA1041879A true CA1041879A (en) | 1978-11-07 |
Family
ID=24090895
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA235,675A Expired CA1041879A (en) | 1974-11-18 | 1975-09-17 | Processing for high permeability silicon steel |
Country Status (14)
Country | Link |
---|---|
US (1) | US3929522A (en) |
JP (1) | JPS5843444B2 (en) |
AR (1) | AR208730A1 (en) |
BE (1) | BE834876A (en) |
CA (1) | CA1041879A (en) |
DE (1) | DE2550426A1 (en) |
ES (1) | ES441705A1 (en) |
FR (1) | FR2291276A1 (en) |
GB (1) | GB1478739A (en) |
IN (1) | IN143003B (en) |
IT (1) | IT1047747B (en) |
PL (1) | PL106073B1 (en) |
SE (1) | SE414949B (en) |
YU (1) | YU291375A (en) |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1558621A (en) * | 1975-07-05 | 1980-01-09 | Zaidan Hojin Denki Jiki Zairyo | High dumping capacity alloy |
US4054470A (en) * | 1976-06-17 | 1977-10-18 | Allegheny Ludlum Industries, Inc. | Boron and copper bearing silicon steel and processing therefore |
US4174235A (en) * | 1978-01-09 | 1979-11-13 | General Electric Company | Product and method of producing silicon-iron sheet material employing antimony |
US4113529A (en) * | 1977-09-29 | 1978-09-12 | General Electric Company | Method of producing silicon-iron sheet material with copper as a partial substitute for sulfur, and product |
US4177091A (en) * | 1978-08-16 | 1979-12-04 | General Electric Company | Method of producing silicon-iron sheet material, and product |
JPS57145963A (en) * | 1981-03-04 | 1982-09-09 | Hitachi Metals Ltd | Material for magnetic head and its manufacture |
JPS6048886B2 (en) * | 1981-08-05 | 1985-10-30 | 新日本製鐵株式会社 | High magnetic flux density unidirectional electrical steel sheet with excellent iron loss and method for manufacturing the same |
JPH01159859U (en) * | 1988-04-28 | 1989-11-06 | ||
US5078808A (en) † | 1990-07-09 | 1992-01-07 | Armco Inc. | Method of making regular grain oriented silicon steel without a hot band anneal |
DE69128624T3 (en) † | 1991-10-21 | 2002-05-29 | Armco Inc., Middletown | Process for the production of normal grain-oriented steel with high silicon and low carbon content |
Family Cites Families (11)
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 |
CA920035A (en) * | 1968-04-27 | 1973-01-30 | Taguchi Satoru | Method for producing an electro-magnetic 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 |
BE790798A (en) * | 1971-11-04 | 1973-02-15 | Armco Steel Corp | Manufacturing process of cube-on-edge orientation 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 |
US3873381A (en) * | 1973-03-01 | 1975-03-25 | Armco Steel Corp | High permeability cube-on-edge oriented silicon steel and method of making it |
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 |
US3855020A (en) * | 1973-05-07 | 1974-12-17 | Allegheny Ludlum Ind Inc | Processing for high permeability silicon steel comprising copper |
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 |
-
1974
- 1974-11-18 US US524846A patent/US3929522A/en not_active Expired - Lifetime
-
1975
- 1975-09-17 CA CA235,675A patent/CA1041879A/en not_active Expired
- 1975-09-22 GB GB38765/75A patent/GB1478739A/en not_active Expired
- 1975-10-09 IT IT51715/75A patent/IT1047747B/en active
- 1975-10-10 ES ES441705A patent/ES441705A1/en not_active Expired
- 1975-10-24 FR FR7532699A patent/FR2291276A1/en active Granted
- 1975-10-27 BE BE2054634A patent/BE834876A/en not_active IP Right Cessation
- 1975-10-29 IN IN2080/CAL/1975A patent/IN143003B/en unknown
- 1975-11-10 DE DE19752550426 patent/DE2550426A1/en active Granted
- 1975-11-13 JP JP50136784A patent/JPS5843444B2/en not_active Expired
- 1975-11-17 YU YU02913/75A patent/YU291375A/en unknown
- 1975-11-18 SE SE7512968A patent/SE414949B/en unknown
- 1975-11-18 AR AR261250A patent/AR208730A1/en active
- 1975-11-18 PL PL1975184805A patent/PL106073B1/en unknown
Also Published As
Publication number | Publication date |
---|---|
US3929522A (en) | 1975-12-30 |
FR2291276B1 (en) | 1981-08-28 |
SE7512968L (en) | 1976-05-19 |
JPS5843444B2 (en) | 1983-09-27 |
DE2550426A1 (en) | 1976-05-20 |
BE834876A (en) | 1976-02-16 |
YU291375A (en) | 1982-02-28 |
AR208730A1 (en) | 1977-02-28 |
DE2550426C2 (en) | 1987-12-23 |
GB1478739A (en) | 1977-07-06 |
IT1047747B (en) | 1980-10-20 |
PL106073B1 (en) | 1979-11-30 |
FR2291276A1 (en) | 1976-06-11 |
IN143003B (en) | 1977-09-17 |
ES441705A1 (en) | 1977-04-01 |
AU8499875A (en) | 1977-03-24 |
SE414949B (en) | 1980-08-25 |
JPS5173922A (en) | 1976-06-26 |
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