CN113930678A - Method for producing ultra-low carbon IF steel based on single RH vacuum treatment and CSP thin slab continuous casting and rolling process - Google Patents

Method for producing ultra-low carbon IF steel based on single RH vacuum treatment and CSP thin slab continuous casting and rolling process Download PDF

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CN113930678A
CN113930678A CN202111127398.1A CN202111127398A CN113930678A CN 113930678 A CN113930678 A CN 113930678A CN 202111127398 A CN202111127398 A CN 202111127398A CN 113930678 A CN113930678 A CN 113930678A
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CN113930678B (en
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尚秀廷
高军
詹卢刚
辛广胜
薛越
张帅
张文博
贾瑞杰
张秀青
杜智俊
郭海东
武晓晶
张文凯
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Baotou Iron and Steel Group Co Ltd
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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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/46—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/10—Handling in a vacuum
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/04—Making ferrous alloys by melting
    • 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
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • 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
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Treatment Of Steel In Its Molten State (AREA)

Abstract

The invention discloses a production method of ultralow-carbon interstitial-free steel based on a single-link RH and CSP process, which comprises the following production process flows of smelting desulfurization, a converter, an RH process, a thin slab continuous casting and rolling CSP process, a cold rolling process, an annealing process and a leveling process, wherein the weight components of ultralow-carbon molten steel used in the smelting process comprise less than or equal to 0.01 percent of C, less than or equal to 0.03 percent of Si, less than or equal to 0.10 percent of Mn, less than or equal to 0.20 percent of P, less than or equal to 0.015 percent of S, less than or equal to 0.01 percent of A1S, less than or equal to 0.06 percent of S, less than or equal to 0.030 percent of Ti, less than or equal to 0.075 percent of N, and the balance of Fe and impurity elements. The refining process adopts single RH vacuum treatment, so that an LF refining process is reduced, the manufacturing cost is reduced, and the steelmaking operation rate is improved; the cold-rolled ultra-low carbon deep drawing IF steel raw material is produced by CSP, and the addition amount of alloy elements is small; has the advantages of low energy consumption, low cost and high efficiency.

Description

Method for producing ultra-low carbon IF steel based on single RH vacuum treatment and CSP thin slab continuous casting and rolling process
Technical Field
The invention relates to the field of interstitial-free IF steel, in particular to a method for producing ultra-low carbon IF steel based on single RH vacuum treatment and CSP thin slab continuous casting and rolling process.
Background
At present, in order to ensure excellent stamping performance of products, cold-rolled deep-drawing steel products used by automobiles in China are mostly designed by components of ultra-low-carbon Interstitial Free (IF) steel, and are produced in a conventional casting machine and a conventional rolling machine, CSP continuous casting and continuous rolling are thin in continuous casting billets and narrow in submerged nozzle channel, and the steel is deoxidized by Al, so that Al is easily generated at a nozzle2O3The inclusion causes steel accumulation at the nozzle, so that the casting process is forced to stop, and the CSP continuous casting and rolling production line produces ultra-low carbon Interstitial Free (IF) steelThe technique of (2) is not mature.
Chinese patent CN105463316A discloses a method for producing ultra-low carbon steel based on FTSC thin slab continuous casting, the C content of the patent is between 0.03 and 0.06 percent, the component requirement of double zero level of the C content of the ultra-low carbon IF steel can not be met, and the stamping property of the steel is inferior to that of the IF steel.
Chinese patent CN 109706284A discloses a method for producing ultra-low carbon IF steel based on CSP thin slab continuous casting machine, the invention gives out the manufacturing process of producing IF steel by CSP in detail, but the smelting link adopts desulphurization-converter-LF-RH process, and compared with the invention, one LF refining process is added, and the manufacturing cost is increased. The patent explains that the main smelting task of the LF furnace is to modify ladle top slag to produce reducing slag, and the ladle top slag can reduce secondary oxidation of molten steel and reduce the effect of oxide at a water gap in the subsequent steel casting process. The invention can solve the problems by strengthening the top slag modification at the end point of the converter, reducing the oxygen content of the steel slag, and carrying out the operations of thorough slag discharge, slag picking ring, covering agent addition and the like on the tundish, and has the advantages of reducing LF refining procedures, reducing cost, shortening time sequence time and the like compared with the CN 109706284A patent.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide a method for producing ultra-low carbon IF steel based on single RH vacuum treatment and CSP thin slab continuous casting and rolling process.
In order to solve the technical problems, the invention adopts the following technical scheme:
the invention relates to a method for producing ultra-low carbon IF steel based on single RH vacuum treatment and CSP thin slab continuous casting and rolling process, which comprises the steps of smelting desulfurization, converter, RH process, thin slab continuous casting and rolling CSP process, cold continuous rolling process, annealing process and leveling process, and is characterized in that the weight components of the low-carbon molten steel are that C is less than or equal to 0.01 percent, Si is less than or equal to 0.02 percent, Mn is more than or equal to 0.10 percent and less than or equal to 0.20 percent, P is less than or equal to 0.015 percent, S is less than or equal to 0.01 percent, A1S is more than or equal to 0.03 percent and less than or equal to 0.06 percent, Ti is more than or equal to 0.030 and less than or equal to 0.075 percent, N is less than or equal to 0.005 percent, and the balance is Fe and impurity elements.
Furthermore, the weight components of the low-carbon molten steel used in the smelting process are that C is less than or equal to 0.004%, Si is less than or equal to 0.01%, Mn is less than or equal to 0.10% and less than or equal to 0.20%, P is less than or equal to 0.015%, S is less than or equal to 0.008%, A1S is more than or equal to 0.04% and less than or equal to 0.055%, Ti is less than or equal to 0.040% and less than or equal to 0.070%, N is less than or equal to 0.004%, O is less than or equal to 0.003%, and the balance is Fe and impurity elements.
Further, the molten iron is pre-desulfurized by adopting a deep desulfurization mode, the S of the molten iron fed into the converter is required to be less than or equal to 0.003 percent, the slag removing area of the molten iron is more than or equal to 95 percent, and the molten iron is fed into the converter as soon as possible after desulfurization and slag removal, so that the pause time is reduced; the molten iron comprises the following components in percentage by mass: p is less than or equal to 0.13 percent and Si is less than or equal to 0.60 percent.
Further, when the converter taps 1/3, ferromanganese is added for deoxidation operation, and 500-1000 kg of lime is added in the tapping process to ensure that the lime is melted; converter endpoint control objective: c: 0.03-0.06%, no more than 300ppm and no more than 500ppm of [ O ], no more than 0.015% of P and no more than 0.01% of S; the number of point blowing times after the carbon pulling operation of the converter is less than or equal to 1; 100 kg-200 kg of aluminum particles are added into the modifying agent, 300 kg-500 kg of the modifying agent is added into the modifying agent, the top slag modification at the end point of the converter is strengthened, and the oxygen content of the steel slag is reduced.
Further, RH vacuum pumping treatment is adopted in the smelting process, and the station entering temperature of molten steel is as follows: performing deoxidation by adopting Al particles at 1580-1650 ℃, wherein the RH ultimate vacuum degree is less than 2mbar, the pure degassing time is more than or equal to 5min after alloying is finished, and the molten steel standing time is more than or equal to 10min after calcium treatment; the molten steel outlet component percentage is as follows: less than or equal to 0.004 percent of C, less than or equal to 0.010 percent of Si, less than or equal to 0.20 percent of Mn, less than or equal to 0.015 percent of P, less than or equal to 0.008 percent of S, less than or equal to 0.03 percent of A1S, less than or equal to 0.06 percent of Ti, less than or equal to 0.030 percent of Ti, less than or equal to 0.075 percent of N, and less than or equal to 0.003 percent of O.
Furthermore, the casting powder for casting uses special ultra-low carbon steel casting powder, the middle ladle adopts a carbon-free covering agent, the whole process is protected from oxidation casting, a long nozzle and a sealing ring are required to be intact in the casting process, and the argon sealing effect of the long nozzle is ensured; the tundish covering agent is to ensure that molten steel is not leaked; in the casting process, the tundish is fully packed, and the nitrogen increase of the tundish is ensured to be less than or equal to 5 ppm; the middle ladle is advanced by 1 furnace to carry out thorough deslagging, slag ring picking and covering agent adding operations, and after the casting is finished, the residual steel operation is carried out, wherein the residual steel is 5-8 tons, so that slag is prevented from being discharged; the casting speed of the casting machine is controlled to be 3.7-4.3 m/s, and the casting speed is stabilized to prevent liquid level fluctuation and slag entrapment.
Furthermore, the thickness of the continuous casting billet is 72mm or 57mm, the tapping temperature of the heating furnace is 1020-1050 ℃, the finishing temperature is controlled within the range of 910 +/-20 ℃, the coiling temperature is controlled within the range of 570-730 ℃, and the post-dispersion laminar cooling is adopted in the cooling mode.
Furthermore, the hot rolling process adopts 7 frames, and the relative reduction ratio of each frame is F1: 35-46%, F2: 35-42%, F3: 33-45%, F4: 23-29%, F5: 25-30%, F6: 19-28% and F7: 13-17%.
Further, the cold continuous rolling process adopts 5-frame cold continuous rolling, and the total cold rolling reduction rate ranges from 50% to 85% according to different thicknesses of finished products; before rolling, pulling, straightening, scale breaking and acid washing are carried out to remove surface iron scale, 0.01 percent of corrosion inhibitor is added into acid washing liquid, the rolling is lubricated by emulsion, and tension rolling is adopted among all the stands.
Further, in the annealing process, the cover annealing temperature is 720-740 ℃, the annealing heat preservation time is 8-17h, and the slow cooling time is 4-6 h; wherein the continuous annealing process comprises the following steps: the annealing temperature is 820-860 ℃, and the flattening elongation is 0.6-1.0%.
Compared with the prior art, the invention has the beneficial technical effects that:
in the method, the refining process adopts single-link RH vacuum treatment, and compared with the conventional refining duplex process, one LF refining process is reduced, the manufacturing cost is reduced, and the steelmaking operation rate is improved; the cold-rolled ultra-low carbon deep-drawing IF steel raw material is produced by CSP, the initial rolling thickness of a finishing mill is larger than that of a conventional rolling mill, the strength of a hot-rolled coil is higher than that of the conventional rolling mill, and the addition amount of alloy elements by adopting the process is small. Compared with a conventional rolling mill, the cold-rolled ultra-low carbon deep-drawing IF steel raw material produced by CSP has the advantages of low energy consumption, low cost and high efficiency, and the surface quality and the performance of the cold-rolled ultra-low carbon deep-drawing IF steel raw material can reach relevant standards and user use requirements.
According to the characteristics of the CSP sheet billet continuous casting and rolling mill, particularly the characteristics that a submerged nozzle has larger reduction rate than a conventional rolling mill and the like, under the condition that other steel mills still adopt a duplex (LF-RH) process for refining, the invention creatively adopts the control of a single-duplex RH process, and achieves the control effect of a duplex process by strictly controlling the process parameters of each process. Compared with the conventional casting machine and rolling mill, the method has the remarkable advantages of short flow, low cost, short smelting time sequence and the like, and greatly improves the market competitiveness of deep-drawing steel products.
Detailed Description
The present invention will be described in further detail with reference to specific examples.
In the following examples, the process flow is: the method comprises the following steps of molten iron desulfurization, converter, RH vacuum treatment, CSP continuous casting and rolling machine, acid cleaning, cold continuous rolling, annealing and flattening.
210t of a converter, 210t of an RH vacuum refining furnace, 57mm or 72mm of continuous casting thickness and 1000-1590mm of blank width of a CSP thin slab continuous casting and rolling machine, wherein the produced steel is ultra-low carbon steel St13, and the steel comprises the following chemical components in percentage by mass: c is less than or equal to 0.004%, Si is less than or equal to 0.01%, Mn: 0.10-0.20%, P is less than or equal to 0.015%, S is less than or equal to 0.008%, Als: 0.040 to 0.055%, Ti: 0.040-0.070%, N is less than or equal to 0.0040%, and O is less than or equal to 0.003%.
Example 1:
and (3) desulfurization: pre-desulfurizing molten iron, namely, performing deep desulfurization on molten iron S: 0.003 percent of the total weight of the slag, 97 percent of the cleaning area of the molten iron slag, and entering the converter process immediately after the molten iron is desulfurized and deslagged. The molten iron comprises the following components in percentage by mass: p: 0.11%, Si: 0.56 percent.
And (3) steel making, wherein the steel tapping temperature is 1640 ℃, when the converter taps 70 tons, 100kg of ferromanganese is added for deoxidation operation, and 800kg of lime is added in the steel tapping process to ensure that the lime is molten. The percentage content of each element at the end point of the converter is as follows: c: 0.04%, O: 0.05%, P: 0.015%, S: 0.008 percent. And point blowing is carried out for 1 time after the carbon drawing operation of the converter. The addition of the aluminum particles is 150kg, the modifying agent is added to 350kg, the top slag modification at the end point of the converter is strengthened, and the oxygen content of the steel slag is reduced.
RH: the station entering temperature of the molten steel is 1620 ℃, the RH treatment period is 40min, the air extraction time is 30min, the decarburization time is 23min, the ultimate vacuum degree is 0bar, 200kg of aluminum particles are added for deoxidation, 170kg of ferrotitanium is added, the pure degassing time is 8min after the alloying is finished, and the standing time of the molten steel is 10min after the calcium treatment, so that the inclusions can fully float. The molten steel outlet component percentage is as follows: c: 0.002%, Si: 0.01%,% Mn: 0.15%, P: 0.015%, S: 0.005%, A1 s: 0.047%, Ti: 0.049%, N: 0.005%, O: 0.003%.
Continuous casting: the superheat degree of the tundish molten steel is 33 ℃, special ultra-low carbon steel covering slag is used for casting, a carbon-free covering agent is adopted in the tundish, the whole-process protection is realized, the non-oxidation casting is realized, the long nozzle and the sealing ring are intact in the casting process, and the argon sealing effect of the long nozzle is ensured; the tundish covering agent completely covers the molten steel so that the molten steel is not exposed and leaked; and carrying out 56 tons of full ladle operation in the casting process. When the tundish is cast in the furnace 1, the operations of completely discharging slag, selecting a slag ring and adding a covering agent are carried out, and the operation of residual steel is carried out after the casting is finished, wherein the residual steel is about 6 tons and does not discharge slag. The casting speed of the casting machine is controlled to be about 3.9m/s, and the casting speed is stabilized to prevent liquid level fluctuation and slag entrapment. The casting machine has smooth casting, and the condition of steel storage and casting stop does not occur.
CSP continuous rolling mill: a7-frame continuous rolling mill is adopted, a casting machine is put into a liquid core and pressed down, the thickness of a continuous casting blank is 57mm, the tapping temperature of a heating furnace is 1025 ℃, the finish rolling temperature is controlled at 920 ℃, the coiling temperature is 600 ℃, and a post-dispersion laminar cooling mode is adopted. The relative reduction ratio of each frame is F1: 40%, F2: 38%, F3: 39%, F4: 26%, F5: 27%, F6: 23% and F7: 16%.
The cold rolling process adopts 5-frame cold continuous rolling, and the total cold rolling reduction rate is 65-85%. Before rolling, pulling, straightening, scale breaking and acid washing are carried out to remove surface iron scale, emulsion lubrication is adopted for rolling, tension rolling is adopted among the frames, a roughening roller is used as a roller, and the friction coefficient is 1.6.
The cover annealing process comprises the steps of annealing at 720 ℃ and 730 ℃, annealing heat preservation time of 10h, 12h and 16h, and slow cooling time of 4 h-6 h; a continuous annealing process: the annealing temperature is 850 ℃, and the leveling elongation is 0.6 percent and 0.8 percent.
The finished product roll obtained by the process has the surface quality reaching FB grade, mechanical property, yield strength of 135 MPa-160 MPa, tensile strength of 280 MPa-300 MPa and elongation (A80 transverse sample): 40% -47%, n value: 0.22-0.24, r value: 2.2 to 2.8. Meets the St14 standard requirement.
Example 2:
and (3) desulfurization: pre-desulfurizing molten iron, namely, performing deep desulfurization on molten iron S: 0.002%, the molten iron slag removing area is 96%, and the molten iron enters the converter process immediately after desulfurization and slag removal. The molten iron comprises the following components in percentage by mass: p: 0.13%, Si: 0.48 percent.
And (3) steel making, wherein the tapping temperature is 1630 ℃, 150kg of ferromanganese is added for deoxidation operation when the converter taps 75 tons, and 1000kg of lime is added in the tapping process to ensure that the lime is molten. The percentage content of each element at the end point of the converter is as follows: c: 0.03%, O: 0.04%, P: 0.014%, S: 0.010%. 130kg of aluminum particles are added, 360kg of modifying agent is added, the top slag modification at the end point of the converter is strengthened, and the oxygen content of the steel slag is reduced.
RH: the station-entering temperature of the molten steel is 1615 ℃, the RH treatment period is 43min, the air extraction time is 32min, the decarburization time is 20min, the ultimate vacuum degree is 0bar, 220kg of aluminum particles are added for deoxidation, 150kg of ferrotitanium is added, the pure degassing time is 9min after the alloying is finished, and the standing time of the molten steel is 12min after the calcium treatment, so that inclusions can fully float upwards. The molten steel outlet component percentage is as follows: c: 0.002%, Si: 0.008:%, Mn: 0.14%, P: 0.013%, S: 0.004%, A1 s: 0.050%, Ti: 0.053%, N: 0.004%, O: 0.0025%.
Continuous casting: the superheat degree of the tundish molten steel is 25 ℃, special ultra-low carbon steel covering slag is used for casting, a carbon-free covering agent is adopted in the tundish, the whole-process protection is realized, the non-oxidation casting is carried out, a long nozzle and a sealing ring are intact in the casting process, and the argon sealing effect of the long nozzle is ensured; the tundish covering agent completely covers the molten steel so that the molten steel is not exposed and leaked; and carrying out 55 tons of full ladle operation in the casting process. When the tundish is cast in the furnace 1, the operations of completely discharging slag, selecting a slag ring and adding a covering agent are carried out, and the operation of residual steel is carried out after the casting is finished, wherein the residual steel is about 8 tons and does not discharge slag. The casting speed of the casting machine is controlled to be about 4.1m/s, and the casting speed is stabilized to prevent liquid level fluctuation and slag entrapment. The casting machine has smooth casting, and the condition of steel storage and casting stop does not occur.
CSP continuous rolling mill: a7-frame continuous rolling mill is adopted, a casting machine is put into a liquid core to be pressed, the thickness of a continuous casting blank is 72mm, the tapping temperature of a heating furnace is 1029 ℃, the final rolling temperature is 910 ℃, the coiling temperature is 710 ℃, and a post-dispersion laminar cooling mode is adopted. The relative reduction ratio of each frame is F1: 38%, F2: 40%, F3: 38%, F4: 28%, F5: 29%, F6: 26% and F7: 19%.
The cold rolling process adopts 5-frame cold continuous rolling, and the total cold rolling reduction rate is 65-85%. Before rolling, pulling, straightening, scale breaking and acid washing are carried out to remove surface iron scale, emulsion lubrication is adopted for rolling, tension rolling is adopted among the frames, a roughening roller is used as a roller, and the friction coefficient is 1.4.
The cover annealing process comprises the steps of annealing at the temperature of 720 ℃, 730 ℃ and 740 ℃, annealing and heat preservation for 10 hours, 12 hours, 14 hours and 16 hours, and slow cooling for 4 hours to 6 hours; a continuous annealing process: the annealing temperature is 860 ℃, and the flattening elongation is 0.6%, 0.7% and 0.8%.
The finished product roll obtained by the process has the surface quality reaching FB grade, mechanical property, yield strength of 142-165 MPa, tensile strength of 285-308 MPa and elongation (A80 transverse sample): 39% -46%, and n value: 0.21 to 0.23, r value: 2.1-2.6, and meets the St13 standard requirement.
The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.

Claims (10)

1. A method for producing ultra-low carbon IF steel based on single RH vacuum treatment and CSP thin slab continuous casting and rolling process is characterized in that: the method comprises the steps of smelting desulfurization, a converter, an RH process, a thin slab continuous casting and rolling CSP process, a cold continuous rolling process, an annealing process and a leveling process, and is characterized in that the weight components of the low-carbon molten steel comprise less than or equal to 0.01% of C, less than or equal to 0.02% of Si, less than or equal to 0.20% of Mn, less than or equal to 0.015% of P, less than or equal to 0.01% of S, less than or equal to 0.03% of A1S, less than or equal to 0.06% of Ti, less than or equal to 0.030% of Ti, less than or equal to 0.075% of N, and the balance of Fe and impurity elements.
2. The method for producing ultra-low carbon IF steel based on single RH vacuum process and CSP thin slab continuous casting and rolling process as claimed in claim 1, wherein: the weight percentage of the low-carbon molten steel used in the smelting process is that C is less than or equal to 0.004%, Si is less than or equal to 0.01%, Mn is more than or equal to 0.10% and less than or equal to 0.20%, P is less than or equal to 0.015%, S is less than or equal to 0.008%, A1S is more than or equal to 0.04% and less than or equal to 0.055%, Ti is more than or equal to 0.040 and less than or equal to 0.070%, N is less than or equal to 0.004%, O is less than or equal to 0.003%, and the rest is Fe and impurity elements.
3. The production method of the single RH ultra low carbon interstitial free steel based on the CSP process as claimed in claim 1, wherein: pre-desulfurizing molten iron by adopting a deep desulfurization mode, wherein S of the molten iron fed into a converter is required to be less than or equal to 0.003 percent, the molten iron slag scarfing area is more than or equal to 95 percent, and the molten iron is fed into the converter as soon as possible after desulfurization and slagging, so that the pause time is reduced; the molten iron comprises the following components in percentage by mass: p is less than or equal to 0.13 percent and Si is less than or equal to 0.60 percent.
4. The production method of the single RH ultra low carbon interstitial free steel based on the CSP process as claimed in claim 1, wherein: when the converter discharges steel to 1/3, ferromanganese is added for deoxidation operation, and 500-1000 kg of lime is added in the process of discharging steel to ensure that the lime is melted; converter endpoint control objective: c: 0.03-0.06%, no more than 300ppm and no more than 500ppm of [ O ], no more than 0.015% of P and no more than 0.01% of S; the number of point blowing times after the carbon pulling operation of the converter is less than or equal to 1; 100 kg-200 kg of aluminum particles are added into the modifying agent, 300 kg-500 kg of the modifying agent is added into the modifying agent, the top slag modification at the end point of the converter is strengthened, and the oxygen content of the steel slag is reduced.
5. The production method of the single RH ultra low carbon interstitial free steel based on the CSP process as claimed in claim 1, wherein: the smelting process adopts RH vacuum pumping treatment, and the station entering temperature of molten steel is as follows: performing deoxidation by adopting Al particles at 1580-1650 ℃, wherein the RH ultimate vacuum degree is less than 2mbar, the pure degassing time is more than or equal to 5min after alloying is finished, and the molten steel standing time is more than or equal to 10min after calcium treatment; the molten steel outlet component percentage is as follows: less than or equal to 0.004 percent of C, less than or equal to 0.010 percent of Si, less than or equal to 0.20 percent of Mn, less than or equal to 0.015 percent of P, less than or equal to 0.008 percent of S, less than or equal to 0.03 percent of A1S, less than or equal to 0.06 percent of Ti, less than or equal to 0.030 percent of Ti, less than or equal to 0.075 percent of N, and less than or equal to 0.003 percent of O.
6. The production method of the single RH ultra low carbon interstitial free steel based on the CSP process as claimed in claim 1, wherein: the casting mold flux is special ultra-low carbon steel mold flux, the tundish adopts a carbon-free covering agent, the whole process is protected and non-oxidation casting is carried out, a long nozzle and a sealing ring are required to be intact in the casting process, and the argon sealing effect of the long nozzle is ensured; the tundish covering agent is to ensure that molten steel is not leaked; in the casting process, the tundish is fully packed, and the nitrogen increase of the tundish is ensured to be less than or equal to 5 ppm; the middle ladle is advanced by 1 furnace to carry out thorough deslagging, slag ring picking and covering agent adding operations, and after the casting is finished, the residual steel operation is carried out, wherein the residual steel is 5-8 tons, so that slag is prevented from being discharged; the casting speed of the casting machine is controlled to be 3.7-4.3 m/s, and the casting speed is stabilized to prevent liquid level fluctuation and slag entrapment.
7. The production method of the single RH ultra-low carbon interstitial free steel based on the CSP process as claimed in claim 1, wherein the thickness of the continuous casting billet is 72mm or 57mm, the tapping temperature of the heating furnace is 1020-1050 ℃, the finish rolling temperature is controlled within the range of 910 +/-20 ℃, the coiling temperature is controlled within the range of 570-730 ℃, and the post-dispersion laminar cooling is adopted in the cooling mode.
8. The method for producing the single RH ultra-low carbon interstitial free steel based on the CSP process as claimed in claim 1, wherein the hot rolling process adopts 7 stands, and the relative reduction ratio of each stand is F1: 35-46%, F2: 35-42%, F3: 33-45%, F4: 23-29%, F5: 25-30%, F6: 19-28%, and F7: 13-17%.
9. The production method of the single RH ultra-low carbon interstitial-free steel based on the CSP process as claimed in claim 1, wherein the cold continuous rolling process adopts 5-frame cold continuous rolling, and the total cold rolling reduction rate ranges from 50% to 85% according to the thickness of the finished product; before rolling, pulling, straightening, scale breaking and acid washing are carried out to remove surface iron scale, 0.01 percent of corrosion inhibitor is added into acid washing liquid, the rolling is lubricated by emulsion, and tension rolling is adopted among all the stands.
10. The production method of the single RH ultra-low carbon interstitial free steel based on the CSP process as claimed in claim 1, wherein the annealing process comprises the following steps of cover annealing at 720-740 ℃, annealing heat preservation for 8-17h, slow cooling for 4-6 h; wherein the continuous annealing process comprises the following steps: the annealing temperature is 820-860 ℃, and the flattening elongation is 0.6-1.0%.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114908209A (en) * 2022-04-02 2022-08-16 山西太钢不锈钢股份有限公司 Method for improving surface quality of cold-rolled deep-drawing steel
CN115305316A (en) * 2022-08-18 2022-11-08 日照钢铁控股集团有限公司 RH single-connection ultra-low carbon steel production method for sheet billet continuous casting and rolling production line
CN115323121A (en) * 2022-08-18 2022-11-11 日照钢铁控股集团有限公司 Smelting process of low-carbon low-sulfur steel for thin slab continuous casting and rolling production line

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1974821A (en) * 2006-12-18 2007-06-06 马鞍山钢铁股份有限公司 Production process of punch level cold rolled steel plate based on CSP technology
CN101550475A (en) * 2009-05-15 2009-10-07 首钢总公司 Method for producing ultra-low-carbon steel
CN103060680A (en) * 2013-01-04 2013-04-24 湖南雪豹电器有限公司 Semi-process cold-rolling non-oriented electrical steel and production process thereof
CN103233162A (en) * 2013-05-04 2013-08-07 河北钢铁股份有限公司唐山分公司 Process for producing IF steel by using medium sheet billet in continuous casting manner
CN103540714A (en) * 2013-10-12 2014-01-29 首钢总公司 Method for smelting high-grade pipe line steel with RH single-link process
CN104233064A (en) * 2014-07-31 2014-12-24 甘肃酒钢集团宏兴钢铁股份有限公司 170MPa-grade cold-rolled phosphorized IF high-strength steel and production method thereof
CN106048392A (en) * 2016-07-18 2016-10-26 华南理工大学 Method for producing semi-processed cold-rolled non-oriented electrical steel rotors and stators by thin slab continuous casting and rolling process
CN108754342A (en) * 2018-06-25 2018-11-06 武汉钢铁有限公司 A kind of inexpensive hyperoxia glassed steel and its manufacturing method of CSP technique productions
CN108796373A (en) * 2018-06-25 2018-11-13 武汉钢铁有限公司 A kind of the generator excitation element steel and its manufacturing method of CSP technique productions
CN108823508A (en) * 2018-06-15 2018-11-16 甘肃酒钢集团宏兴钢铁股份有限公司 A kind of half flow harden steel band of 590MPa and its bell furnace production technology
CN108842024A (en) * 2018-06-15 2018-11-20 甘肃酒钢集团宏兴钢铁股份有限公司 A kind of phosphorous IF high-strength steel band of 390MPa grades of cold rolling and its LF-RH duplex production technology
CN109706284A (en) * 2019-01-31 2019-05-03 邯郸钢铁集团有限责任公司 A method of ultra low carbon IF steel is produced based on CSP thin-slab caster
CN110144524A (en) * 2019-06-04 2019-08-20 甘肃酒钢集团宏兴钢铁股份有限公司 A kind of 440MPa grades of cold rolling gap-free atom high-strength steel and its CSP+BAF production method

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1974821A (en) * 2006-12-18 2007-06-06 马鞍山钢铁股份有限公司 Production process of punch level cold rolled steel plate based on CSP technology
CN101550475A (en) * 2009-05-15 2009-10-07 首钢总公司 Method for producing ultra-low-carbon steel
CN103060680A (en) * 2013-01-04 2013-04-24 湖南雪豹电器有限公司 Semi-process cold-rolling non-oriented electrical steel and production process thereof
CN103233162A (en) * 2013-05-04 2013-08-07 河北钢铁股份有限公司唐山分公司 Process for producing IF steel by using medium sheet billet in continuous casting manner
CN103540714A (en) * 2013-10-12 2014-01-29 首钢总公司 Method for smelting high-grade pipe line steel with RH single-link process
CN104233064A (en) * 2014-07-31 2014-12-24 甘肃酒钢集团宏兴钢铁股份有限公司 170MPa-grade cold-rolled phosphorized IF high-strength steel and production method thereof
CN106048392A (en) * 2016-07-18 2016-10-26 华南理工大学 Method for producing semi-processed cold-rolled non-oriented electrical steel rotors and stators by thin slab continuous casting and rolling process
CN108823508A (en) * 2018-06-15 2018-11-16 甘肃酒钢集团宏兴钢铁股份有限公司 A kind of half flow harden steel band of 590MPa and its bell furnace production technology
CN108842024A (en) * 2018-06-15 2018-11-20 甘肃酒钢集团宏兴钢铁股份有限公司 A kind of phosphorous IF high-strength steel band of 390MPa grades of cold rolling and its LF-RH duplex production technology
CN108754342A (en) * 2018-06-25 2018-11-06 武汉钢铁有限公司 A kind of inexpensive hyperoxia glassed steel and its manufacturing method of CSP technique productions
CN108796373A (en) * 2018-06-25 2018-11-13 武汉钢铁有限公司 A kind of the generator excitation element steel and its manufacturing method of CSP technique productions
CN109706284A (en) * 2019-01-31 2019-05-03 邯郸钢铁集团有限责任公司 A method of ultra low carbon IF steel is produced based on CSP thin-slab caster
CN110144524A (en) * 2019-06-04 2019-08-20 甘肃酒钢集团宏兴钢铁股份有限公司 A kind of 440MPa grades of cold rolling gap-free atom high-strength steel and its CSP+BAF production method

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114908209A (en) * 2022-04-02 2022-08-16 山西太钢不锈钢股份有限公司 Method for improving surface quality of cold-rolled deep-drawing steel
CN114908209B (en) * 2022-04-02 2023-11-24 山西太钢不锈钢股份有限公司 Method for improving surface quality of cold-rolled deep-drawing steel
CN115305316A (en) * 2022-08-18 2022-11-08 日照钢铁控股集团有限公司 RH single-connection ultra-low carbon steel production method for sheet billet continuous casting and rolling production line
CN115323121A (en) * 2022-08-18 2022-11-11 日照钢铁控股集团有限公司 Smelting process of low-carbon low-sulfur steel for thin slab continuous casting and rolling production line

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