CN115058661A - High-carbon high-manganese steel plate and production method thereof - Google Patents

High-carbon high-manganese steel plate and production method thereof Download PDF

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Publication number
CN115058661A
CN115058661A CN202210690162.7A CN202210690162A CN115058661A CN 115058661 A CN115058661 A CN 115058661A CN 202210690162 A CN202210690162 A CN 202210690162A CN 115058661 A CN115058661 A CN 115058661A
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carbon
manganese steel
manganese
carbon high
steel plate
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Inventor
谢世正
周剑丰
邓必荣
肖爱达
邓之勋
隋亚飞
尹振芝
刘彭
苟宽
陈杰
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Hunan Valin Lianyuan Iron & Steel Co Ltd
Lysteel Co Ltd
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Hunan Valin Lianyuan Iron & Steel Co Ltd
Lysteel Co Ltd
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Priority to CN202210690162.7A priority Critical patent/CN115058661A/en
Publication of CN115058661A publication Critical patent/CN115058661A/en
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/16—Controlling or regulating processes or operations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/16—Controlling or regulating processes or operations
    • B22D11/166—Controlling or regulating processes or operations for mould oscillation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/16—Controlling or regulating processes or operations
    • B22D11/18—Controlling or regulating processes or operations for pouring
    • 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
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/06—Deoxidising, e.g. killing
    • 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
    • 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)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Treatment Of Steel In Its Molten State (AREA)

Abstract

The application discloses a high-carbon high-manganese steel plate and a production method thereof. The application provides a high carbon high manganese steel sheet, by mass percent, the component of high carbon high manganese steel sheet includes: c: 0.90-1.40%, Mn: 11.0 to 14.0%, Si: 0.30-0.70%, P is less than or equal to 0.035%, S is less than or equal to 0.020%, Al: 0.015 to 0.10 percent, and the balance of Fe and inevitable impurities. According to the method, through adjustment of various production process parameters in the high-carbon high-manganese steel plate, bonding steel leakage can be effectively controlled, the generation of longitudinal cracks on the surface of the casting blank can be effectively controlled, the thickness of the casting blank is reduced, the center segregation and center porosity rating of the casting blank are better, the requirements of a steel rolling process can be met, the generation of longitudinal cracks on the surface of the high-carbon high-manganese steel plate is reduced, the quality of the high-carbon high-manganese steel plate is improved, the production cost is reduced, and the CSP stable and efficient production of the high-carbon high-manganese steel plate is realized.

Description

High-carbon high-manganese steel plate and production method thereof
Technical Field
The application belongs to the technical field of steel plate manufacturing, and particularly relates to a high-carbon high-manganese steel plate and a production method thereof.
Background
The high-carbon high-manganese steel plate has good toughness and remarkable surface work hardening characteristic, under the action of strong impact load or extrusion load, the stressed surface is work hardened, the surface hardness can be improved from about initial HB170 level to more than HB550 level, and the interior still maintains good impact toughness, so the high-carbon high-manganese steel plate is widely applied to mining equipment, mechanical manufacturing industry and other aspects. Currently, high carbon and high manganese steel sheets can be produced by a die casting method or in a conventional slab caster, and no report on the production of high carbon and high manganese steel sheets by continuous casting and rolling (CSP) has been found before.
However, in the process of producing the high-carbon high-manganese steel plate by the conventional plate continuous casting machine, the defects of bonding bleed-out and serious longitudinal cracks of a casting blank exist, and further the high-carbon high-manganese steel plate obtained by hot continuous rolling has the problems of more longitudinal cracks and high production cost.
Disclosure of Invention
In view of the above, the present application provides a high-carbon high-manganese steel sheet and a method for producing the same, which aims to reduce the generation of longitudinal cracks on the surface of the high-carbon high-manganese steel sheet and reduce the production cost thereof through a CSP production method.
In one aspect, an embodiment of the present application provides a high-carbon high-manganese steel sheet, where the high-carbon high-manganese steel sheet includes, by mass: c: 0.90-1.40%, Mn: 11.0-14.0%, Si: 0.30-0.70%, P is less than or equal to 0.035%, S is less than or equal to 0.020%, Al: 0.015 to 0.10 percent, and the balance of Fe and inevitable impurities.
According to an embodiment of one aspect of the present application, the high carbon high manganese steel sheet has a longitudinal crack occurrence rate of 1.6% or less.
According to an embodiment of one aspect of the present application, the metallographic structure of the high-carbon high-manganese steel sheet is an austenitic structure.
In another aspect, an embodiment of the present application provides a method for producing a high-carbon high-manganese steel sheet, including:
a molten iron smelting process, wherein molten iron and scrap steel are added into a converter to be smelted in the converter to obtain molten steel;
a molten steel smelting process, namely adding an aluminum block and a manganese alloy into the molten steel for deoxidation alloying when the molten steel is tapped from a converter and transferred into a ladle, and refining in a refining furnace to obtain refined molten steel with the carbon content of 0.90-1.40% and the manganese content of 11.0-14.0%, wherein the drainage sand in the ladle is chromium drainage sand;
a continuous casting process, in which refined molten steel is injected into a tundish in an argon atmosphere, the molten steel of the tundish is poured into a crystallizer, and continuous casting is carried out to obtain a casting blank, wherein the continuous casting comprises primary cooling and secondary cooling, the superheat degree of the molten steel of the tundish during the pouring is 5-25 ℃, and the drawing speed during the continuous casting is 3.0-3.5 m/min;
and a steel rolling procedure, namely, carrying out hot continuous rolling on the casting blank, carrying out laminar cooling, reeling and flattening to obtain the high-carbon high-manganese steel plate.
According to another aspect of the present application, in the hot metal smelting process, the volume of scrap added to the converter is less than 1m 3 。
According to an embodiment of another aspect of the present application, the hydrogen content in the refined molten steel is 7-12ppm in the continuous casting process.
According to an embodiment of another aspect of the present application, the melting point of the mold flux in the mold is 780 ℃ to 850 ℃ in the continuous casting process.
According to another aspect of the examples of the present application, the basicity of the mold flux is 0.8 to 1.0 in the continuous casting process.
According to an example of another aspect of the present application, the mass fraction of lithium oxide in the mold flux is 1.5 to 2.5% based on the total mass of the mold flux.
According to another embodiment of the present application, the mold is vibrated in a non-sinusoidal manner during the continuous casting process.
According to another aspect of the embodiment of the present application, the non-sinusoidal vibrations have a vibration frequency of 260-280 times/min, an amplitude of 4.4-4.8mm and a skewness of 30%.
According to another embodiment of the present application, in the continuous casting process, the specific water amount of the secondary cooling is 1.0-1.2L/kg.
According to another aspect of the present invention, the thickness of the cast slab is 60 to 65mm in the continuous casting process and the rolling process.
According to another aspect of the present invention, in the steel rolling process, the high carbon and high manganese steel sheet has a thickness of 1.2 to 6.0 mm.
Compared with the prior art, the application has at least the following beneficial effects:
the method comprises the following steps of: the regulation of the temperature of superheat degree pouring, the continuous casting pulling speed, the hydrogen content in molten steel, the melting point and the alkalinity of crystallizer covering slag, the vibration mode of a crystallizer and the like can effectively control the bonding bleed-out, effectively control the generation of longitudinal cracks on the surface of a casting blank and reduce the thickness of the casting blank, and the center segregation and center porosity of the casting blank are better graded, thereby meeting the requirements of a steel rolling process, improving the quality of a high-carbon high-manganese steel plate, reducing the production cost and realizing the stable and efficient production of the high-carbon high-manganese steel plate by CSP. The embodiment shows that the longitudinal crack occurrence rate of the high-carbon high-manganese steel plate is less than or equal to 1.6%, and meanwhile, on the basis that the thickness of a casting blank is 60-65mm, the thinnest thickness of the high-carbon high-manganese steel plate produced in a CSP mode can reach 1.2mm, the thinnest thickness of the existing high-carbon high-manganese steel plate is broken through, and the high-carbon high-manganese steel plate has good mechanical properties. In addition, the production method of the high-carbon high-manganese steel plate has the advantages of small process control difficulty, strong operability, simplicity and the like.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for a person skilled in the art to obtain other drawings based on the drawings without any creative effort.
FIG. 1 is a low-order graph of a high-carbon high-manganese cast slab according to example 1.
FIG. 2 is a metallographic structure diagram of a high-carbon high-manganese steel sheet according to example 1.
Detailed Description
In order to make the application purpose, technical solution and beneficial technical effects of the present application clearer, the present application is further described in detail with reference to the following embodiments. It should be understood that the embodiments described in this specification are only for the purpose of explaining the present application and are not intended to limit the present application.
For the sake of brevity, only some numerical ranges are explicitly disclosed herein. However, any lower limit may be combined with any upper limit to form ranges not explicitly recited; and any lower limit may be combined with any other lower limit to form a range not explicitly recited, and similarly any upper limit may be combined with any other upper limit to form a range not explicitly recited. Also, although not explicitly recited, each point or individual value between endpoints of a range is encompassed within the range. Thus, each point or individual value can form a range not explicitly recited as its own lower or upper limit in combination with any other point or individual value or in combination with other lower or upper limits.
In the description herein, it is to be noted that, unless otherwise specified, "above" and "below" are inclusive, and "a plurality" of "one or more" means two or more.
The above summary of the present application is not intended to describe each disclosed embodiment or every implementation of the present application. The following description more particularly exemplifies illustrative embodiments. At various points throughout this application, guidance is provided through a list of embodiments that can be used in various combinations. In each instance, the list is merely a representative group and should not be construed as exhaustive.
At present, the conventional continuous casting production of high-carbon high-manganese steel mainly has three problems: 1) the high-temperature linear expansion coefficient of the steel is 1.5-2.0 times of that of the common steel, and if the casting blank is improperly controlled in the solidification and cooling processes, stress concentration and cracks are easily generated. 2) The carbon content (0.95%) and the manganese content (12.5%) in steel are high, the liquidus temperature is only about 1400 ℃, and is 100 ℃ lower than that of normal steel, so that only casting powder with low melting point can be selected, otherwise, the bonding breakout accident is easily caused, but the casting powder with too low melting point is unfavorable for controlling the longitudinal cracks of casting blanks. 3) C, Mn are strong segregation elements, C, Mn content of steel is high, and casting blanks can generate central segregation, looseness and other conditions, so that defects such as layering and the like easily occur during steel rolling.
Therefore, in order to solve the problems in the production of the conventional high carbon and high manganese steel, the inventors have conducted a great deal of research aiming at reducing the generation of longitudinal cracks on the surface of the high carbon and high manganese steel sheet and reducing the production cost thereof by the CSP production method.
High carbon high manganese steel plate
The embodiment of the first aspect of the application provides a high-carbon high-manganese steel plate, which comprises the following components in percentage by mass: c: 0.90-1.40%, Mn: 11.0 to 14.0%, Si: 0.30-0.70%, P is less than or equal to 0.035%, S is less than or equal to 0.020%, Al: 0.015 to 0.10 percent, and the balance of Fe and inevitable impurities.
The high-carbon high-manganese steel plate provided by the embodiment of the application has higher carbon content and manganese content, the generation rate of longitudinal cracks on the surface of the high-carbon high-manganese steel plate is low, in some embodiments, the longitudinal crack generation rate of the high-carbon high-manganese steel plate is less than or equal to 1.6%, and the central segregation and loosening conditions of a casting blank are good.
According to the embodiment of the present application, C in the high carbon and high manganese steel sheet composition can significantly improve the strength and hardness of the high carbon and high manganese steel sheet through a solid solution strengthening effect. The C content may be 0.90%, 1.0%, 1.1%, 1.2%, 1.3%, or 1.40%, or may be a combination of any of the above values.
In some embodiments, the metallographic structure of the high-carbon high-manganese steel sheet may be an austenitic structure.
According to the embodiment of the application, Mn is beneficial to improving hardenability, expanding an austenite phase region, delaying the transformation of ferrite, pearlite and bainite, and also can stabilize residual austenite, thereby being beneficial to improving the plastic toughness of the high-carbon high-manganese steel plate. However, since too high Mn content causes center segregation and porosity, and deteriorates the mechanical properties of the steel sheet, the Mn content in the high-carbon high-manganese steel sheet of the present application is controlled to 11.0 to 14.0%. For example, the Mn content may be 11.0%, 11.5%, 12.0%, 12.5%, 13%, 13.5%, or 14%, or may be a combination of any of the above values.
The Si element has a solid solution strengthening effect, and is beneficial to improving the content and stability of austenite and improving the ductility and toughness of steel. Comprehensively considered, the content of Si element in the high-carbon high-manganese steel plate is 0.30-0.70%. For example, the Si content may be 0.30%, 0.40%, 0.50%, 0.60%, or 0.70%, or may be a combination of any of the above values.
P, S is a harmful element, which is not beneficial to the improvement of the performance of the high-carbon high-manganese steel plate, the P element is partially gathered at the crystal boundary to obviously improve the brittleness, the S element can lead the high-carbon high-manganese steel plate to generate hot brittleness, the ductility and the toughness of the steel are reduced, and cracks are easily caused during forging and rolling, therefore, on the basis of not influencing the performance of the high-carbon high-manganese steel plate, the P content and the S content can be respectively limited within the range of less than or equal to 0.035% and less than or equal to 0.020%.
Al element is used as a deoxidizing and nitrogen-fixing agent in steelmaking, so that the grain structure of the steel plate can be refined, and the toughness of the steel at low temperature is improved; simultaneously, the temperature of the phase transition point can be greatly improved, and Al with high melting point and stability is formed 2 O 3 Protecting the film and improving the wear resistance and fatigue strength of the steel. If the content of the Al element is more than 0.10%, graphitization of the steel is promoted, and the concentration of carbon dissolved in an alloy phase is reduced, thereby resulting in a decrease in hardness and strength of the steel sheet.
According to the embodiment of the application, under the combined action of the elements, the high-carbon high-manganese steel plate has low longitudinal crack incidence rate and good surface quality.
Production method of high-carbon high-manganese steel plate
The application also provides a production method of the high-carbon high-manganese steel plate, which comprises the following steps:
s10, a molten iron smelting procedure, namely adding molten iron and scrap steel into a converter for converter smelting to obtain molten steel;
s20, a molten steel smelting procedure, namely adding an aluminum block and a manganese alloy into the molten steel for deoxidation alloying when the molten steel is tapped from a converter and transferred into a ladle, and refining in a refining furnace to obtain refined molten steel with the carbon content of 0.90-1.40% and the manganese content of 11.0-14.0%, wherein the drainage sand in the ladle is chromium drainage sand;
s30, a continuous casting process, wherein the refined molten steel is injected into a tundish in an argon atmosphere, the tundish molten steel is poured into a crystallizer, and continuous casting is carried out to obtain a casting blank, wherein the continuous casting comprises primary cooling and secondary cooling, the superheat degree of the tundish molten steel is 5-25 ℃ during pouring, and the drawing speed is 3.0-3.5m/min during continuous casting;
and S40, a steel rolling procedure, namely performing hot continuous rolling, laminar cooling, coiling and flattening on the casting blank to obtain the high-carbon high-manganese steel plate.
The embodiment of the application comprises the following steps of carrying out the following steps on the high-carbon high-manganese steel plate: the temperature of superheat degree pouring, the continuous casting pulling speed, the melting point and the alkalinity of the crystallizer casting powder, the vibration mode of the crystallizer and the like are adjusted, so that the bonding breakout can be effectively controlled, the generation of longitudinal cracks of a casting blank can be effectively controlled, the thickness of the casting blank is reduced, the center segregation and center porosity of the casting blank are well graded, the requirements of a steel rolling process can be met, the production cost is reduced, and the CSP can stably and efficiently produce the high-carbon high-manganese steel plate. Meanwhile, the production method of the high-carbon high-manganese steel plate has the advantages of small process control difficulty, strong operability, simplicity and the like.
According to the embodiment of the application, the chromite diversion sand used in the step S20 is composed of chromite and additives, has the advantages of high specific gravity, good fluidity, high melting point, no excessive sintering and the like, and the addition amount of the chromite in the chromite diversion sand is 60-70% of the mass of the chromite diversion sand, which is beneficial to the drainage sand to form a continuous sintering layer. In addition, under the high-temperature condition, FeO in the chromite reacts and desolventizes to form secondary spinel, so that the volume of a sintering layer is changed to generate cracks, the automatic casting of the molten steel can be ensured, and the process needs argon protection.
According to the embodiment of the application, after the refined molten steel is poured into the tundish in the step S30, when the tonnage of the tundish reaches about 25 tons, the molten steel of the tundish is poured into the crystallizer, and the superheat degree of the molten steel of the tundish during pouring is 5-25 ℃. The low-superheat pouring can not only realize high pulling speed, but also reduce overflow accidents, improve the quality of the inner part and the outer part of a casting blank, reduce the tapping temperature and prolong the service life of a furnace lining.
In some embodiments, the draw rate during continuous casting may be 3.0-3.5m/min, for example, the draw rate during continuous casting may be 3.0m/min, 3.1m/min, 3.2m/min, 3.3m/min, 3.4m/min, or 3.5m/min, or any combination thereof.
In some embodiments, the scrap volume of the scrap charged into the converter may be less than 1m in the molten iron smelting process 3 。
According to the embodiment of the application, the volume of the scrap steel can be fully melted and utilized in the converter smelting process, and if the volume of the scrap steel is more than 1m 3 The utilization rate of the scrap steel is low, and the increase of N in the smelting process is caused, which is not beneficial to the high-carbon high-manganese steel plateAnd (4) improving the quality.
In some embodiments, the hydrogen content in the refined molten steel may be 7-12ppm in the continuous casting process. For example, the hydrogen content in the refined molten steel may be 7ppm, 8ppm, 9ppm, 10ppm, 11ppm, or 12ppm, or a combination of any of the foregoing.
According to the embodiment of the present application, the refined molten steel in the above-described hydrogen content range can prevent the mold heat flow from being too high, resulting in longitudinal cracks of the cast slab. Meanwhile, when the hydrogen in the molten steel is cooled, if the hydrogen cannot escape in time and is accumulated in the structure, high-pressure fine pores are formed, so that the plasticity, toughness and fatigue strength of the steel are rapidly reduced, and even cracks and brittle fracture are caused, therefore, the hydrogen content in the refined molten steel needs to be controlled below 12 ppm.
In some embodiments, the melting point of the mold flux in the mold may be 780 ℃ to 850 ℃ in the continuous casting process.
According to the embodiment of the application, the crystallizer casting powder in the melting point range is used, the bonding and the steel leakage of the casting blank can be prevented, the generation of longitudinal cracks of the casting blank is favorably controlled, and the crystallizer casting powder has good lubricating and heat transfer functions in the high-casting-speed continuous casting process.
In some embodiments, the basicity of the mold flux in the mold may be 0.8 to 1.0.
According to the embodiment of the application, the covering slag under the alkalinity has stronger capability of absorbing impurities and simultaneously absorbs a small amount of Al 2 O 3 The performance of the post-covering slag is still stable, and the smooth production and the surface quality of the casting blank are ensured.
In some embodiments, the mass fraction of lithium oxide in the mold flux is 1.5 to 2.5% based on the total mass of the mold flux.
According to the examples of the present application, lithium oxide in a mass fraction of 1.5 to 2.5% can improve the glass properties of the mold flux and make the stability of the mold flux more stable.
In some embodiments, the mold may be vibrated in a non-sinusoidal manner during the continuous casting process.
In some embodiments, the non-sinusoidal vibration may have a vibration frequency of 260-280 times/min, an amplitude of 4.4-4.8mm, and a slope of 30%. For example, the vibration frequency of the non-sinusoidal vibration may be 260 times/min, 265 times/min, 270 times/min, 275 times/min, or 280 times/min, or may be any combination range of any of the above values. The amplitude of the non-sinusoidal vibrations may be 4.4mm, 4.5mm, 4.6mm, 4.7mm or 4.8mm, and may range in any combination of any of the above values.
According to the embodiment of the application, the vibration mode of the crystallizer is non-sinusoidal vibration, namely the upward vibration time of the crystallizer is longer than the downward vibration time, so that the relative movement speed between the casting blank and the upward vibration of the crystallizer is reduced. In the application, the vibration frequency, amplitude and deflection rate of non-sinusoidal vibration are controlled within the ranges, so that the possibility of steel leakage caused by adhesion between the billet shell of the casting billet at the high drawing speed and the wall of the crystallizer can be reduced.
In some embodiments, the specific amount of water for the secondary cooling in the continuous casting process may be 1.0 to 1.2L/kg. For example, the specific water amount for the secondary cooling may be 1.0L/kg, 1.06L/kg, 1.0L/kg, 1.15L/kg or 1.2L/kg, or may be any combination of the above values.
According to the embodiment of the application, the surface temperature distribution of the casting blank in the secondary cooling zone, the casting blank cracks and segregation can be influenced by the specific water amount, the specific water amount in the range of 1.0-1.2L/kg can shorten the casting blank time, improve the casting blank speed, reduce the production cost, and ensure that the obtained casting blank does not generate longitudinal cracks and the center segregation is slight.
In some embodiments, the thickness of the cast slab may be 60 to 65mm in the continuous casting process and the rolling process. For example, the thickness of the cast slab may be 60mm, 61mm, 62mm, 63mm, 64mm or 65mm, or may be any combination of the above values.
According to the embodiment of the application, the thickness of the casting blank obtained by the production method can reach 60-65mm, and the thickness of the casting blank is thinner than that of a high-carbon high-manganese steel casting blank produced by a conventional method, so that a good foundation can be laid for obtaining a thinner high-carbon high-manganese steel plate in a subsequent steel rolling process.
In some embodiments, the thickness of the high carbon high manganese steel sheet may be 1.2-6.0mm in the steel rolling process. For example, the thickness of the high-carbon high-manganese steel plate may be 1.2mm, 1.5mm, 2mm, 2.6mm, 3.0mm, 3.5mm, 4.0mm, 5.0mm, or 6.0mm, or any combination of the above values. Preferably, the thickness of the high-carbon high-manganese steel plate is 1.2-3.0 mm.
According to the embodiment of the application, on the basis that the thickness of a casting blank is 60-65mm, the thinnest thickness of the high-carbon high-manganese steel plate produced in the CSP mode can reach 1.2mm, the thinnest thickness of the existing high-carbon high-manganese steel plate is broken through, and the high-carbon high-manganese steel plate has good mechanical properties and is free of crack generation.
According to the embodiment of the application, through adjusting various production process parameters in the high-carbon high-manganese steel plate, the bonding breakout can be effectively controlled, the thickness of a casting blank is reduced, the generation of longitudinal cracks on the surface of the high-carbon high-manganese steel plate is reduced, the production cost is reduced, the CSP can stably and efficiently produce the high-carbon high-manganese steel plate, meanwhile, the casting blank low-power rating center segregation is 0.5-1.5 grade of C, the porosity is 0.5-1.0 grade, the requirements of a subsequent steel rolling process are well met, and no layering defect exists during rolling. The high-carbon high-manganese steel plate can be used in various fields such as automobiles, ships, machinery and the like.
Examples
The present disclosure is more particularly described in the following examples that are intended as illustrative only, since various modifications and changes within the scope of the present disclosure will be apparent to those skilled in the art. Unless otherwise indicated, all parts, percentages, and ratios reported in the following examples are on a weight basis, and all reagents used in the examples are commercially available or synthesized according to conventional methods and can be used directly without further treatment, and the equipment used in the examples is commercially available.
Example 1
(1) The high-carbon high-manganese steel plate comprises the following target components: c: 1.1%, Mn: 13.0%, Si: 0.45%, P: 0.0220%, S: 0.002%, Al: 0.032%, and the balance of Fe and inevitable impurities;
(2) smelting by adopting a 100t converter, adding molten iron and scrap steel into the converter, wherein the adding amount of the molten iron is 75 tons/furnace, the adding amount of the scrap steel is 15 tons/furnace, the total loading amount is 90 tons/furnace, the bulk degree of the added scrap steel is less than 1000mm, and a bottom argon blowing mode is adopted in the whole process;
(3) the end point phosphorus content of the converter smelting process is 0.015 percent, the carbon content is 0.10 percent, and the end point temperature is 1628 ℃;
(4) a ladle filled with 80kg of high-chromium drainage sand is adopted, and molten steel is filled in the ladle baked to 860 ℃.
(5) The deoxidizer added in the tapping process is an aluminum block, the addition amount of the deoxidizer is 1.0 kg/ton of steel, the manganese alloy is metal manganese and high manganese, the addition amounts of the deoxidizer and the manganese are 3 tons/furnace and 2 tons/furnace respectively, the flow rate of argon blown at the bottom of the steel ladle is 1000L/min before tapping and in the tapping process, and the soft blowing flow rate of an argon station is 400L/min;
(6) after the ladle enters an LF furnace refining process, feeding the ladle into a station to transmit electricity for slagging, and starting arc by adopting 1-gear current and heating by adopting 5-8-gear current; 600kg of lime and 600kg of pre-melted slag are properly added in the power transmission process according to the submerged arc condition. LF is electrified to reach about 1620 ℃ to carry out slagging and desulfurization, and in the process, the H content in the molten steel is adjusted by coke powder, wherein the H content is 12 ppm.
(7) After the alloy is added, argon is added and the mixture is stirred for 5min, the slag surface condition is observed, the mixture is sampled after the components are uniform, and continuous casting and pouring are carried out after the components and the temperature are qualified.
(8) Before continuous casting is started, the air tightness of an argon pipeline for blowing argon to the long nozzle is detected, the argon flow is opened to 300L/min, soap water is smeared at the joint of the pipeline and a hose connected with the argon blowing nozzle of the long nozzle, and if soap bubbles are not generated, the air tightness is good. Purging tundish with argon gas for 5min before casting, and adding acidic covering agent (SiO) during casting and casting 2 85 percent by mass), the argon flow of the long nozzle is 150L/min, and the N content of the molten steel in the continuous casting tundish is increased by 2 ppm.
(9) And (3) pouring molten steel in the ladle into the tundish through the ladle long nozzle, and pouring the molten steel in the tundish into the crystallizer through the tundish lower nozzle when the tonnage of the tundish reaches 15 tons.
(10) The tundish temperature was 1415 ℃ and the degree of superheat was 25 ℃ (liquidus temperature 1395 ℃).
(11) The alkalinity of the protective slag is 0.9 plus or minus 0.1, the viscosity at 1300 ℃ is 0.06-0.12 Pa.s, the melting temperature is 800-850 ℃, and the consumption rate is 0.54kg/t steel.
(12) The continuous casting drawing speed is 3.0m/min, the vibration frequency of the crystallizer vibration is 260 times/min, the amplitude is 4.8mm, and the waveform deflection rate is 30%.
(13) The specific water amount of the secondary cooling during continuous casting was set to 1.0L/kg.
(14) A cast slab having a thickness of 70mm was pressed to a thickness of 60mm by liquid core reduction.
(15) The casting blank is straightened and then directly enters a heating furnace, the casting blank is cut off by pendulum shear after reaching the fixed length, the casting blank is in the furnace for 30 minutes, the tapping temperature is 1250 ℃, and the casting blank is rolled to the thickness of 1.2mm by a 7-frame.
Example 2
(1) The high-carbon high-manganese steel plate comprises the following target components: c: 0.9%, Mn: 14.0%, Si: 0.6%, P: 0.020%, S: 0.002%, Al: 0.05%, the balance being Fe and inevitable impurities;
(2) smelting by adopting a 100t converter, adding molten iron and scrap steel into the converter, wherein the adding amount of the molten iron is 75 tons/furnace, the adding amount of the scrap steel is 15 tons/furnace, the total loading amount is 90 tons/furnace, the bulk degree of the added scrap steel is less than 1000mm, and a bottom argon blowing mode is adopted in the whole process;
(3) the end point phosphorus content of the converter smelting process is 0.012 percent, the carbon content is 0.10 percent, and the end point temperature is 1620 ℃;
(4) a ladle filled with 80kg of high-chromium drainage sand is adopted, and molten steel is filled in the ladle baked to 860 ℃.
(5) The deoxidizer added in the tapping process is an aluminum block, the addition amount of the deoxidizer is 1.0 kg/ton of steel, the manganese alloy is metal manganese and high manganese, the addition amounts of the deoxidizer and the manganese are 3 tons/furnace and 2 tons/furnace respectively, the flow rate of argon blown at the bottom of the steel ladle is 1000L/min before tapping and in the tapping process, and the soft blowing flow rate of an argon station is 400L/min;
(6) after the ladle enters an LF furnace refining process, feeding the ladle into a station to transmit electricity for slagging, and starting arc by adopting 1-gear current and heating by adopting 5-8-gear current; 600kg of lime and 600kg of pre-melted slag are properly added in the power transmission process according to the submerged arc condition. LF is electrified to reach about 1620 ℃ to carry out slagging and desulfurization, and in the process, the H content in the molten steel is adjusted by coke powder, wherein the H content is 9 ppm.
(7) After the alloy is added, argon is added and the mixture is stirred for 7min, the slag surface condition is observed, the mixture is sampled after the components are uniform, and continuous casting and pouring are carried out after the components and the temperature are qualified.
(8) Before continuous casting is started, the air tightness of an argon pipeline for blowing argon to the long nozzle is detected, the flow of the argon is opened to 300L/min, soap water is smeared at the joint of the pipeline and a hose connected with the argon blowing port of the long nozzle, and if soap bubbles are not generated, the air tightness is good. Purging tundish with argon gas for 5min before casting, and adding acidic covering agent (SiO) during casting and casting 2 85 percent by mass), the argon flow of the long nozzle is 150L/min, and the N content of the molten steel in the continuous casting tundish is increased by 3 ppm.
(9) And (3) pouring molten steel in the ladle into the tundish through the ladle long nozzle, and pouring the molten steel in the tundish into the crystallizer through the tundish lower nozzle when the tonnage of the tundish reaches 15 tons.
(10) The tundish temperature was 1418 ℃ and the degree of superheat was 15 ℃ (liquidus temperature 1403 ℃).
(11) The alkalinity of the protective slag is 0.9 +/-0.1, the viscosity at 1300 ℃ is 0.06-0.12 Pa.s, the melting temperature is 800-850 ℃, and the consumption rate is 0.53kg/t steel.
(12) The continuous casting speed is 3.2m/min, the vibration frequency of the crystallizer vibration is 270 times/min, the amplitude is 4.6mm, and the waveform skewness is 30%.
(13) The specific water amount of the secondary cooling during continuous casting was set to 1.0L/kg.
(14) A cast slab having a thickness of 70mm was pressed to a thickness of 65mm by liquid core reduction.
(15) The casting blank is straightened and then directly enters a heating furnace, the casting blank is cut off by pendulum shear after reaching the fixed length, the casting blank is in the furnace for 30 minutes, the tapping temperature is 1220 ℃, and the casting blank is rolled to the thickness of 6.0mm by a 7-frame.
Example 3
(1) The high-carbon high-manganese steel plate comprises the following target components: c: 1.4%, Mn: 14%, Si: 0.45%, P: 0.03%, S: 0.002%, Al: 0.04% and the balance of Fe and inevitable impurities;
(2) smelting by adopting a 100t converter, adding molten iron and scrap steel into the converter, wherein the adding amount of the molten iron is 75 tons/furnace, the adding amount of the scrap steel is 15 tons/furnace, the total loading amount is 90 tons/furnace, the bulk degree of the added scrap steel is less than 1000mm, and a bottom argon blowing mode is adopted in the whole process;
(3) the end point phosphorus content of the converter smelting process is 0.019%, the carbon content is 0.10%, and the end point temperature is 1630 +/-10 ℃;
(4) a ladle filled with 80kg of high-chromium drainage sand is adopted, and molten steel is filled in the ladle baked to 860 ℃.
(5) The deoxidizer added in the tapping process is an aluminum block, the addition amount of the deoxidizer is 1.0 kg/ton of steel, the manganese alloy is metal manganese and high manganese, the addition amounts of the deoxidizer and the manganese are 3 tons/furnace and 2 tons/furnace respectively, the flow rate of argon blown at the bottom of the steel ladle is 1000L/min before tapping and in the tapping process, and the soft blowing flow rate of an argon station is 400L/min;
(6) after the ladle enters an LF furnace refining process, feeding the ladle into a station to transmit electricity for slagging, and starting arc by adopting 1-gear current and heating by adopting 5-8-gear current; 600kg of lime and 600kg of pre-melted slag are properly added in the power transmission process according to the submerged arc condition. LF is electrified to reach about 1620 ℃ to carry out slagging and desulfurization, and in the process, the H content in the molten steel is adjusted by coke powder, wherein the H content is 7 ppm.
(7) After the alloy is added, argon is added and the mixture is stirred for 6min, the slag surface condition is observed, the mixture is sampled after the components are uniform, and continuous casting and pouring are carried out after the components and the temperature are qualified.
(8) Before continuous casting is started, the air tightness of an argon pipeline for blowing argon to the long nozzle is detected, the flow of the argon is opened to 300L/min, soap water is smeared at the joint of the pipeline and a hose connected with the argon blowing port of the long nozzle, and if soap bubbles are not generated, the air tightness is good. Purging tundish with argon gas for 5min before casting, and adding acidic covering agent (SiO) during casting and casting 2 85 percent by mass), the argon flow of the long nozzle is 150L/min, and the N content of the molten steel in the continuous casting tundish is increased by 2 ppm.
(9) And (3) pouring molten steel in the ladle into the tundish through the ladle long nozzle, and pouring the molten steel in the tundish into the crystallizer through the tundish lower nozzle when the tonnage of the tundish reaches 15 tons.
(10) The tundish temperature was 1375 ℃ and the superheat degree was 5 ℃ (liquidus temperature 1370 ℃).
(11) The alkalinity of the protective slag is 0.9 plus or minus 0.1, the viscosity at 1300 ℃ is 0.06-0.12 Pa.s, the melting temperature is 800-850 ℃, and the consumption rate is 0.50kg/t steel.
(12) The continuous casting drawing speed is 3.5m/min, the vibration frequency of the crystallizer vibration is 280 times/min, the amplitude is 4.4mm, and the waveform skewness is 30%.
(13) The specific water amount of the secondary cooling during continuous casting was set to 1.2L/kg.
(14) A cast slab having a thickness of 70mm was pressed to a thickness of 60mm by liquid core reduction.
(15) And (3) straightening the casting blank, directly feeding the casting blank into a heating furnace, cutting the casting blank by using pendulum shear after the casting blank reaches a fixed size, and rolling the casting blank to the thickness of 2.0mm through a 7-frame at the tapping temperature of 1250 ℃ within 30 minutes.
Test section
The physical and chemical properties of the casting blank and the high-carbon high-manganese steel plate prepared in the embodiment 1-3 are tested, and the specific test method comprises the following steps:
center segregation: grading by adopting a YBT 4003-2016 continuous casting steel plate billet low-order structure defect grading diagram;
center loosening: grading by adopting a YBT 4003-2016 continuous casting steel plate billet low-order structure defect grading diagram;
incidence of longitudinal cracking: and counting the total length of the longitudinal crack defect/the total cast length of the slab meter and detector by 100 percent.
The results of the physical and chemical properties of the slabs and the high-carbon high-manganese steel sheets prepared in examples 1 to 3 are shown in table 1.
TABLE 1 test results of physical and chemical properties of casting blank and high-carbon high-manganese steel plate
Example 1 Example 2 Example 3
Casting blank center segregation grade Class C class 1.0 stage Class C0.5 stage Class C class 1.5 grade
Casting blank center porosity grade 1.0 stage Grade 0.5 1.0 stage
Incidence of longitudinal cracking 1.0％ 1.2％ 1.6％
As can be seen from the results of the physicochemical properties of the high-carbon high-manganese steel sheet in table 1 above, the casting blanks of examples 1 to 3 had good center segregation and porosity conditions and the high-carbon high-manganese steel sheet had a low incidence of longitudinal cracking in the CSP production mode. Further, as is clear from FIG. 1, the cast slab of example 1 had a smooth and bright surface and no longitudinal cracks. As is clear from fig. 2, the metallographic structure of the high-carbon high-manganese steel sheet of example 1 was an austenitic structure.
In summary, the method can effectively control the bonding breakout and reduce the thickness of the casting blank by adjusting various production process parameters in the high-carbon high-manganese steel plate, and the center segregation and center porosity of the casting blank are better rated, so that the requirements of a steel rolling process can be met, further the generation of longitudinal cracks on the surface of the high-carbon high-manganese steel plate is reduced, the production cost is reduced, and the CSP can stably and efficiently produce the high-carbon high-manganese steel plate. Next, it is understood from the examples that the high-carbon high-manganese steel sheet provided by the present invention has a longitudinal crack incidence of 1.6% or less. In addition, the production method of the high-carbon high-manganese steel plate has the advantages of small process control difficulty, strong operability, simplicity and the like.
While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (10)

1. The high-carbon high-manganese steel plate is characterized by comprising the following components in percentage by mass: c: 0.90-1.40%, Mn: 11.0 to 14.0%, Si: 0.30-0.70%, P is less than or equal to 0.035%, S is less than or equal to 0.020%, Al: 0.015 to 0.10 percent, and the balance of Fe and inevitable impurities.
2. The high-carbon high-manganese steel sheet according to claim 1, characterized in that the high-carbon high-manganese steel sheet has a longitudinal crack incidence of 1.6% or less.
3. The high-carbon high-manganese steel sheet according to claim 1, characterized in that the metallographic structure of the high-carbon high-manganese steel sheet is an austenitic structure.
4. A production method for producing the high-carbon high-manganese steel sheet described in any one of claims 1 to 3, characterized by comprising:
a molten iron smelting process, wherein molten iron and scrap steel are added into a converter to be smelted in the converter to obtain molten steel;
a molten steel smelting process, wherein when the molten steel is tapped from a converter and transferred into a ladle, an aluminum block and a manganese alloy are added into the molten steel for deoxidation alloying, and refining is carried out by a refining furnace, so as to obtain refined molten steel with the carbon content of 0.90-1.40% and the manganese content of 11.0-14.0%, wherein the drainage sand in the ladle is chromium drainage sand;
a continuous casting process, wherein the refined molten steel is injected into a tundish in an argon atmosphere, the tundish pours the molten steel of the tundish into a crystallizer, and continuous casting is carried out to obtain a casting blank, wherein the continuous casting comprises primary cooling and secondary cooling, the superheat degree of the molten steel of the tundish during casting is 5-25 ℃, and the drawing speed during continuous casting is 3.0-3.5 m/min;
and a steel rolling procedure, namely performing hot continuous rolling, laminar cooling, coiling and flattening on the casting blank to obtain the high-carbon high-manganese steel plate.
5. The method for manufacturing a high-carbon high-manganese steel sheet according to claim 4, wherein the volume of scrap added to the converter in the hot metal smelting process is less than 1m 3 。
6. The method of claim 4, wherein the refined molten steel contains 7 to 12ppm of hydrogen in the continuous casting step.
7. The method for producing a high-carbon high-manganese steel sheet according to claim 4, wherein in the continuous casting process, the melting point of the mold flux in the mold is 780 ℃ to 850 ℃; and/or
The alkalinity of the covering slag is 0.8-1.0; and/or
Based on the total mass of the mold flux, the mass fraction of lithium oxide in the mold flux is 1.5-2.5%.
8. The method for producing a high-carbon high-manganese steel sheet according to claim 4, wherein the mold is vibrated in a non-sinusoidal manner in the continuous casting step;
wherein the vibration frequency of the non-sinusoidal vibration is 260-280 times/min, the amplitude is 4.4-4.8mm, and the skewness is 30%.
9. The method for producing a high-carbon high-manganese steel sheet according to claim 4, wherein the specific amount of water for the secondary cooling is 1.0 to 1.2L/kg in the continuous casting step.
10. The method for producing a high-carbon high-manganese steel sheet according to claim 4, wherein the thickness of the cast slab is 60 to 65mm in the continuous casting process and the rolling process;
in the steel rolling process, the thickness of the high-carbon high-manganese steel plate is 1.2-6.0 mm.
CN202210690162.7A 2022-06-17 2022-06-17 High-carbon high-manganese steel plate and production method thereof Pending CN115058661A (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030145911A1 (en) * 2001-06-13 2003-08-07 Harald Hoffmann Highly stable, steel and steel strips or steel sheets cold-formed, method for the production of steel strips and uses of said steel
US20080164003A1 (en) * 2005-03-05 2008-07-10 Jens Kempken Method and Installation for Producing Light Gauge Steel with a High Manganese Content
CN110205461A (en) * 2019-07-04 2019-09-06 山西太钢不锈钢股份有限公司 A kind of manufacturing method of the high manganese wear-resistant steel plate of high-carbon
CN112522624A (en) * 2020-11-30 2021-03-19 湖南华菱涟源钢铁有限公司 High manganese austenitic wear-resistant steel and manufacturing method thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030145911A1 (en) * 2001-06-13 2003-08-07 Harald Hoffmann Highly stable, steel and steel strips or steel sheets cold-formed, method for the production of steel strips and uses of said steel
US20080164003A1 (en) * 2005-03-05 2008-07-10 Jens Kempken Method and Installation for Producing Light Gauge Steel with a High Manganese Content
CN110205461A (en) * 2019-07-04 2019-09-06 山西太钢不锈钢股份有限公司 A kind of manufacturing method of the high manganese wear-resistant steel plate of high-carbon
CN112522624A (en) * 2020-11-30 2021-03-19 湖南华菱涟源钢铁有限公司 High manganese austenitic wear-resistant steel and manufacturing method thereof

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Application publication date: 20220916