CN101748259B - Method for producing high-magnetic-induction oriented silicon steel by low-temperature heating - Google Patents
Method for producing high-magnetic-induction oriented silicon steel by low-temperature heating Download PDFInfo
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- CN101748259B CN101748259B CN2008102297712A CN200810229771A CN101748259B CN 101748259 B CN101748259 B CN 101748259B CN 2008102297712 A CN2008102297712 A CN 2008102297712A CN 200810229771 A CN200810229771 A CN 200810229771A CN 101748259 B CN101748259 B CN 101748259B
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- nitriding
- silicon steel
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- oriented silicon
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- 229910000976 Electrical steel Inorganic materials 0.000 title claims abstract description 21
- 238000010438 heat treatment Methods 0.000 title claims abstract description 16
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 12
- 238000000137 annealing Methods 0.000 claims abstract description 38
- 238000000034 method Methods 0.000 claims abstract description 27
- 238000005121 nitriding Methods 0.000 claims abstract description 24
- 238000005097 cold rolling Methods 0.000 claims abstract description 18
- 239000011248 coating agent Substances 0.000 claims abstract description 13
- 238000000576 coating method Methods 0.000 claims abstract description 13
- 230000006698 induction Effects 0.000 claims abstract description 8
- 238000005098 hot rolling Methods 0.000 claims abstract description 7
- 239000010419 fine particle Substances 0.000 claims abstract description 6
- 229910010413 TiO 2 Inorganic materials 0.000 claims description 3
- 238000009413 insulation Methods 0.000 claims description 2
- 238000005261 decarburization Methods 0.000 abstract description 4
- 239000011521 glass Substances 0.000 abstract description 2
- 238000005461 lubrication Methods 0.000 abstract description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 abstract 2
- 229910052681 coesite Inorganic materials 0.000 abstract 1
- 229910052906 cristobalite Inorganic materials 0.000 abstract 1
- 239000000377 silicon dioxide Substances 0.000 abstract 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract 1
- 229910052682 stishovite Inorganic materials 0.000 abstract 1
- 229910052905 tridymite Inorganic materials 0.000 abstract 1
- 239000003112 inhibitor Substances 0.000 description 17
- 239000000047 product Substances 0.000 description 11
- 229910000831 Steel Inorganic materials 0.000 description 8
- 239000010959 steel Substances 0.000 description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 239000012528 membrane Substances 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 5
- 229910004298 SiO 2 Inorganic materials 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 238000003723 Smelting Methods 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000009749 continuous casting Methods 0.000 description 2
- 239000004615 ingredient Substances 0.000 description 2
- 238000012856 packing Methods 0.000 description 2
- 238000001953 recrystallisation Methods 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 239000002932 luster Substances 0.000 description 1
- HCWCAKKEBCNQJP-UHFFFAOYSA-N magnesium orthosilicate Chemical compound [Mg+2].[Mg+2].[O-][Si]([O-])([O-])[O-] HCWCAKKEBCNQJP-UHFFFAOYSA-N 0.000 description 1
- 229910052919 magnesium silicate Inorganic materials 0.000 description 1
- 235000019792 magnesium silicate Nutrition 0.000 description 1
- 239000000391 magnesium silicate Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
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- Manufacturing Of Steel Electrode Plates (AREA)
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
Abstract
The invention discloses a method for producing high magnetic induction oriented silicon steel by low temperature heating, which comprises the steps of heating an oriented silicon steel slab produced by a common process, then carrying out hot rolling, annealing or normalizing the hot rolled slab, carrying out primary high reduction cold rolling to the thickness close to a finished product, carrying out decarburization annealing in a wet atmosphere, then carrying out nitriding, coating a separant, and finally carrying out high temperature annealing, and is characterized in that: the heating temperature of the plate blank is controlled below 1280 ℃; before nitriding of decarburization annealing plate, 1.5% -3% critical deformation cold rolling is carried out under the condition of no lubrication to destroy SiO2A film; the separant is Al with the size less than 10um2O3Fine particles with a weight percentage of 5% ~ up to30％TiO2. The invention solves the problem of SiO formed on the surface of the decarburization annealing plate2The film can prevent nitriding and obtain excellent performance of the bottom layer of the glass film.
Description
Technical field
The present invention relates to a kind of production method of high magnetic induction grain-oriented silicon steel, especially a kind of method of producing high magnetic induction grain-oriented silicon steel by low temperature heating.
Background technology
At present, the orientation silicon steel production technology flow process is generally: blast furnace ironmaking → converter smelting → external refining → continuous casting+induction stirring → strand spraying oxygen-proof film → heating and hot rolling → normalizing (Hi-B) → cold rolling → process annealing (GO) → secondary cold-rolling (GO) → decarburizing annealing and coating MgO separant → finished product high temperature annealing → hot-leveling stretch and anneal and coating coating insulating film → rewinding packing.
In industrial scale, the control techniques of inhibitor can be divided into two classes.A kind of is common technology, and promptly slab is heated to more than the solid solubility temperature of inhibitor (as AlN and MnS),, is called " method of inherent inhibitor " (＞1300 ℃) so that their disperses are separated out; Another kind of by company of Nippon Steel " obtain inhibitor method " (1100～1200 ℃) that grow up, be that slab heating temperature is enough low, the necessary inhibitor of secondary recrystallization is to finish in decarburizing annealing to form before beginning to final finished annealed secondary recrystallization, its means are exactly nitriding in steel, make it to combine with original element in the steel, be formed with (Al, Si) the N precipitate of inhibitor function.
Making when being the Hi-B oriented silicon steel of intrinsic inhibitor with AlN+MnS, the Heating temperature of strand＞1300 ℃, and adopt the once cold rolling draft rolling greater than 85% heavy reduction rate, more most important is to guarantee to separate out from making steel the normalizing process AlN disperse.
In course of hot rolling, finishing temperature must be more than 1100 ℃, because silicon steel must be from the zone fast cooling of γ-phase volume fraction greater than set-point; Because requiring to have volume fraction is γ-phase of 40%～50%, Si content is 3.25% o'clock, and the C content of requirement is 0.07%～0.08%.These characteristics have caused the following difficulty of developing new product.
The heat difficulty
Heat makes iron scale many, and lumber recovery is low; Repair stove rate height, output reduces; Fuel consumption is many; Furnace campaign is short; The manufacturing cost height; Surface defects of products increases.
(1) increases Si content difficulty
If will reduce iron loss by increasing silicone content, also must increase C content, yet, increasing the decarburization difficulty that C content makes silicon steel, the result can cause the hysteresis of finished product.
(2) produce thin specification silicon steel product difficulty
With cold rolling draft approximately is 87% to produce thin slab product, needs to reduce hot rolled coil thickness specification.Yet, can not keep high finishing temperature again to the hot rolled coil that is lower than specific grade.
For fear of with the metallurgy problem of AlN as intrinsic inhibitor manufacturing Hi-B oriented silicon steel, also in order to make product innovation, the normal now acquisition inhibitor method that adopts the slab low-temperature heat.The manufacturing processed of intrinsic inhibitor and acquisition inhibitor method is basic identical, makes the Hi-B product by the method for once cold rolling.The essential distinction of two kinds of methods is as shown in table 1, and the method that obtains inhibitor is inhibitor with AlN, adopts the heating of low temperature slab, will carry out nitriding after the decarburizing annealing.
The characteristics of two kinds of manufacture method of table 1
Mn forms MnO and can be used as MgO and SiO after decarburizing annealing
2The catalyst of reaction has improved the glassy membrane quality.MnS has played effective function when forming glassy membrane.With AlN is main inhibitor, does not re-use MnS when adopting the method for above-mentioned acquisition inhibitor to produce oriented silicon steel, and the decarburizing annealing rear surface forms the thick SiO of 10～20nm
2Film is a very big obstacle to nitriding.
Summary of the invention
The object of the present invention is to provide a kind of method of producing high magnetic induction grain-oriented silicon steel by low temperature heating, solve the SiO that decarburizing annealing plate surface forms
2Film hinders the problem of nitriding, simultaneously the good glassy membrane bottom of obtained performance.
For achieving the above object, the main technical schemes taked of the present invention is as follows:
(1) will then carry out hot rolling with the directional silicon steel slab of common explained hereafter in heating below 1280 ℃, hot-rolled sheet annealing or normalizing are rolled down near finished product thickness after a heavy reduction rate is cold rolling, carry out decarburizing annealing again in wet atmosphere;
(2) the decarburizing annealing plate carries out 1.5%～3% the cold rolling SiO that destroys of critical strain under not lubricated situation
2Film then carries out nitriding and handles, and nitriding temperature is 830～870 ℃; Nitriding time is 5～50 seconds; Nitriding medium is NH
3
(3) on the surface of steel plate after the nitriding, be coated with the fine particle Al of size＜10um with electrostatic method
2O
3, wherein adding weight percent is 5%～30%TiO
2
(4) finally manufacture the Hi-B oriented silicon steel of excellent property through high temperature annealing, the smooth annealing of thermal stretch and coating insulating coating.
When adopting the production of acquisition inhibitor method to be the low temperature Hi-B oriented silicon steel of inhibitor, must handle the inhibition ability of strengthening AlN by nitriding after the decarburizing annealing with AlN, but the fine and close SiO that in the decarburizing annealing process, forms
2Film can make the control breakdown of nitriding ability.Under not lubricated situation, cold rolling through 1.5%～3% critical strain, broken SiO
2Oxide film carries out so that nitriding process is easier.
MgO and SiO
2Reaction forms magnesium silicate glass film bottom in high-temperature annealing process, now because the cold rolling SiO that destroyed of critical strain
2Film, the glassy membrane degradation of formation.Because Al
2O
3Not with SiO
2React, with the fine particle Al of size＜10um
2O
3As the main separant of high temperature annealing, do not form glassy membrane behind the high temperature annealing, surperficial metal luster, the punching performance obviously improves, P
1.7Also reduce.
The present invention compared with prior art has following beneficial effect:
1) the decarburizing annealing plate is cold rolling through 1.5%～3% critical strain under not lubricated situation, can effectively destroy the SiO that forms after the decarburizing annealing
2Surface film oxide improves nitriding efficient;
2) You Yi Al
2O
3Coating does not form the glassy membrane bottom, and the top layer is even, obtains good magnetic performance;
3) guaranteed the enforcement of smooth annealing of subsequent thermal and insulating coating.
Embodiment
The present invention is further described by the following embodiment.
1, technology general requirement
(1) technical process:
Blast furnace ironmaking → converter smelting → external refining → continuous casting → heating and hot rolling → heavy reduction rate once cold rolling → decarburizing annealing → critical strain is cold rolling → and nitriding handles → is coated with Al
2O
3Separant → finished product high temperature annealing → hot-leveling stretches and anneals and coating coating insulating film → rewinding packing
(2) molten steel chemical ingredients (weight percent): 0.02%～0.09%C, 2.8%～3.8%Si, 0.01%～0.2%Mn ,≤0.035%P, 0.001%～0.02%S ,≤0.01%N ,≤0.03%Als, all the other are iron and a small amount of inclusion;
(3) strand is gone into furnace temp 〉=300 ℃, and best 〉=900 ℃ are at 1200 ℃～1280 ℃ scope insulation＜3h, then carry out hot rolling, hot-rolled sheet annealing or normalizing are rolled down near finished product thickness after a heavy reduction rate is cold rolling, carry out decarburizing annealing again in wet atmosphere;
(4) before the nitridation process, the decarburizing annealing plate is earlier cold rolling through 1.5%～3% critical strain under lubrication circumstances not, again under 830～870 ℃ temperature, and decomposing N H
3Carrying out the nitriding of 5～50s in the atmosphere handles;
(5) on the surface of steel plate after the nitriding, be coated with the fine particle Al of size＜10um with electrostatic method
2O
3, wherein adding weight percent is 5%～30%TiO
2
(6) finally manufacture the Hi-B oriented silicon steel of excellent property through high temperature annealing, the smooth annealing of thermal stretch and coating insulating coating.
2, specific embodiment
Get composition strand as shown in table 2, average mark was slit into 6 after crop truncated, and tested according to above-mentioned technology respectively.The processing parameter and the magnetic property detected result of test see Table 3.
The table 2 experiment chemical ingredients (wt%) of steel
| C | Si | Mn | P | S | Als | N |
| 0.055 | 3.3 | 0.20 | 0.033 | ≤0.005 | 0.03 | 0.008 |
Claims (2)
1. the method for a producing high magnetic induction grain-oriented silicon steel by low temperature heating, to heat with the directional silicon steel slab of common explained hereafter, then carry out hot rolling, hot-rolled sheet annealing or normalizing are after a heavy reduction rate is cold rolling, be rolled down near finished product thickness, in wet atmosphere, carry out decarburizing annealing again, carry out nitriding afterwards, the coating separant, carry out high temperature annealing at last, it is characterized in that: slab is gone into furnace temp and is 〉=300 ℃, and heating and temperature control is at 1200 ℃～1280 ℃ scopes, insulation＜3h; The decarburizing annealing plate carries out 1.5%～3% the cold rolling SiO that destroys of critical strain before the nitriding under not lubricated situation
2Film; The nitriding temperature of decarburizing annealing plate is 830～870 ℃, and nitriding time is 5～50 seconds, and nitriding medium is NH
3Described separant is Al
2O
3Fine particle, wherein adding weight percent is 5%～30%TiO
2
2. the method for producing high magnetic induction grain-oriented silicon steel by low temperature heating according to claim 1 is characterized in that: separant Al
2O
3Fine particle size＜10um, and apply with electrostatic method.
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| CN101748259B true CN101748259B (en) | 2011-12-07 |
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Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102041440B (en) * | 2011-01-16 | 2012-01-25 | 首钢总公司 | Method for producing high magnetic induction grain-oriented silicon steel |
| CN105492634B (en) | 2013-08-27 | 2018-12-14 | Ak钢铁产权公司 | Grain oriented electrical steel with improved forsterite coating characteristic |
| CN107245646B (en) * | 2017-06-01 | 2018-10-16 | 东北大学 | A kind of preparation method of plate face circumferential direction high-magnetic induction, low-iron loss non-orientation silicon steel |
| CN110551968A (en) * | 2018-06-04 | 2019-12-10 | 武汉尚瑞科技有限公司 | High magnetic induction grain-oriented silicon steel nitriding annealing production method and product thereof |
| CN110055489A (en) * | 2019-04-19 | 2019-07-26 | 武汉钢铁有限公司 | The rapid nitridation method of low temperature high magnetic induction grain-oriented silicon steel |
| CN116287626B (en) * | 2023-03-23 | 2023-09-15 | 首钢智新迁安电磁材料有限公司 | Method for improving magnetic uniformity of oriented silicon steel |
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|---|---|---|---|---|
| CN1228817A (en) * | 1996-08-30 | 1999-09-15 | 阿奇亚斯佩丝阿里特尔尼公司 | Process for production of grain oriented electrical steel strip having high magnetic characteristics, starting from thin slab |
| CN1254021A (en) * | 1998-09-18 | 2000-05-24 | 川崎制铁株式会社 | Grain-oriented silicon-iron plate with excellent tectorial memebrane property and magnetic property |
| CN1400319A (en) * | 2001-07-24 | 2003-03-05 | 川崎制铁株式会社 | Manufacture of directional electromagnetic steel plate |
| CN1461357A (en) * | 2001-04-23 | 2003-12-10 | 新日本制铁株式会社 | Unidirectional silicon steel sheet excellent in adhesion of insulating coating film imparting tensile force and its mfg. method |
| CN1743128A (en) * | 2005-09-29 | 2006-03-08 | 东北大学 | Method for producing oriented silicon steel band by direct rolling of continuous cast plate slab |
| CN1796587A (en) * | 2004-12-27 | 2006-07-05 | 宝山钢铁股份有限公司 | Orientating silicon steel, manufacturing process and equipment |
-
2008
- 2008-12-12 CN CN2008102297712A patent/CN101748259B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1228817A (en) * | 1996-08-30 | 1999-09-15 | 阿奇亚斯佩丝阿里特尔尼公司 | Process for production of grain oriented electrical steel strip having high magnetic characteristics, starting from thin slab |
| CN1254021A (en) * | 1998-09-18 | 2000-05-24 | 川崎制铁株式会社 | Grain-oriented silicon-iron plate with excellent tectorial memebrane property and magnetic property |
| CN1461357A (en) * | 2001-04-23 | 2003-12-10 | 新日本制铁株式会社 | Unidirectional silicon steel sheet excellent in adhesion of insulating coating film imparting tensile force and its mfg. method |
| CN1400319A (en) * | 2001-07-24 | 2003-03-05 | 川崎制铁株式会社 | Manufacture of directional electromagnetic steel plate |
| CN1796587A (en) * | 2004-12-27 | 2006-07-05 | 宝山钢铁股份有限公司 | Orientating silicon steel, manufacturing process and equipment |
| CN1743128A (en) * | 2005-09-29 | 2006-03-08 | 东北大学 | Method for producing oriented silicon steel band by direct rolling of continuous cast plate slab |
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| CN101748259A (en) | 2010-06-23 |
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Inventor after: Jiang Qiwu Inventor after: Jin Wenxu Inventor after: Pang Shufang Inventor after: You Qinglei Inventor after: Fu Yongjun Inventor after: Zhang Jing Inventor after: Zhang Haili Inventor before: Jiang Qiwu Inventor before: Jin Wenxu Inventor before: Pang Shufang Inventor before: You Qinglei Inventor before: Fu Yongjun Inventor before: Zhang Jing Inventor before: Zhang Haili |
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