CN110643887A - Ultra-low carbon steel for deep drawing and production process thereof - Google Patents
Ultra-low carbon steel for deep drawing and production process thereof Download PDFInfo
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- 229910001209 Low-carbon steel Inorganic materials 0.000 title claims abstract description 36
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 12
- 238000000034 method Methods 0.000 claims abstract description 66
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 65
- 239000010959 steel Substances 0.000 claims abstract description 65
- 230000008569 process Effects 0.000 claims abstract description 54
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 49
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 30
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 30
- 239000001301 oxygen Substances 0.000 claims abstract description 30
- 238000007670 refining Methods 0.000 claims abstract description 29
- 238000007664 blowing Methods 0.000 claims abstract description 25
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 24
- 238000009749 continuous casting Methods 0.000 claims abstract description 20
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 18
- 239000002893 slag Substances 0.000 claims abstract description 18
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 18
- 238000005261 decarburization Methods 0.000 claims abstract description 14
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 12
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 11
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 10
- 239000000463 material Substances 0.000 claims abstract description 10
- 239000012535 impurity Substances 0.000 claims abstract description 6
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 37
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 31
- 238000010079 rubber tapping Methods 0.000 claims description 30
- 238000005096 rolling process Methods 0.000 claims description 27
- 239000010936 titanium Substances 0.000 claims description 26
- 238000003723 Smelting Methods 0.000 claims description 14
- 239000002245 particle Substances 0.000 claims description 14
- 229910052742 iron Inorganic materials 0.000 claims description 13
- 229910001200 Ferrotitanium Inorganic materials 0.000 claims description 11
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 10
- 239000010703 silicon Substances 0.000 claims description 8
- 239000011593 sulfur Substances 0.000 claims description 7
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 6
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 6
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 5
- 229910052786 argon Inorganic materials 0.000 claims description 5
- 229910052791 calcium Inorganic materials 0.000 claims description 5
- 239000011575 calcium Substances 0.000 claims description 5
- 239000002131 composite material Substances 0.000 claims description 4
- 238000007872 degassing Methods 0.000 claims description 3
- 238000005070 sampling Methods 0.000 claims description 3
- 229910000629 Rh alloy Inorganic materials 0.000 claims description 2
- 238000005275 alloying Methods 0.000 claims description 2
- 238000009529 body temperature measurement Methods 0.000 claims description 2
- 230000004907 flux Effects 0.000 claims description 2
- 230000001681 protective effect Effects 0.000 claims description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims 6
- 229910052681 coesite Inorganic materials 0.000 claims 3
- 229910052906 cristobalite Inorganic materials 0.000 claims 3
- 239000000377 silicon dioxide Substances 0.000 claims 3
- 229910052682 stishovite Inorganic materials 0.000 claims 3
- 229910052905 tridymite Inorganic materials 0.000 claims 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims 2
- 229910052593 corundum Inorganic materials 0.000 claims 2
- 238000002844 melting Methods 0.000 claims 2
- 230000008018 melting Effects 0.000 claims 2
- 230000000717 retained effect Effects 0.000 claims 2
- 229910001845 yogo sapphire Inorganic materials 0.000 claims 2
- KKCBUQHMOMHUOY-UHFFFAOYSA-N Na2O Inorganic materials [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 claims 1
- 238000006477 desulfuration reaction Methods 0.000 claims 1
- 230000023556 desulfurization Effects 0.000 claims 1
- 238000005266 casting Methods 0.000 abstract description 10
- 230000000694 effects Effects 0.000 abstract description 7
- 230000024121 nodulation Effects 0.000 abstract description 6
- 230000000052 comparative effect Effects 0.000 description 13
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 238000001514 detection method Methods 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 2
- 229910000976 Electrical steel Inorganic materials 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 235000011941 Tilia x europaea Nutrition 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 239000004571 lime Substances 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 2
- 238000012797 qualification Methods 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
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- 239000000112 cooling gas Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 238000004925 denaturation Methods 0.000 description 1
- 230000036425 denaturation Effects 0.000 description 1
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- 238000007689 inspection Methods 0.000 description 1
- 238000005495 investment casting Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
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- 239000007921 spray Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 238000009864 tensile test Methods 0.000 description 1
- 238000009489 vacuum treatment Methods 0.000 description 1
Classifications
-
- 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
- C22C33/06—Making ferrous alloys by melting using master alloys
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
-
- 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
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
- B22D11/111—Treating the molten metal by using protecting powders
-
- 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
- C21C7/0006—Adding metallic additives
-
- 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
- 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
- C21C7/068—Decarburising
-
- 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
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- 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
- C22C38/004—Very low carbon steels, i.e. having a carbon content of less than 0,01%
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- 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
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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
- C22C38/06—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)
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- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention discloses an ultra-low carbon steel for deep drawing and a production process thereof, wherein the ultra-low carbon steel comprises the following components in percentage by weight: less than or equal to 0.010 percent of C, less than or equal to 0.08 percent of Si, less than or equal to 0.20 percent of Mn, less than or equal to 0.025 percent of P, less than or equal to 0.020 percent of S, more than or equal to 0.020 percent of Al, 0.050 to 0.120 percent of Ti, and the balance of Fe and inevitable impurities. The final oxygen content of the converter is controlled, the RH process carries out natural decarburization, the RH oxygen blowing decarburization link is omitted, the ultra-low carbon special covering slag and the tundish carbon-free covering agent are adopted in the continuous casting process, so that the carburization amount in the process is greatly reduced, the Al and Ti elements are added in sequence, the grain refining effect is realized, and the strength of the material is improved by the separated Ti (CN). Finally, the castability of the molten steel is improved, casting nodulation is reduced, the production efficiency is improved, and key indexes of the material such as purity, deep drawing performance and strength are effectively improved.
Description
Technical Field
The invention belongs to the field of metallurgy, and relates to ultra-low carbon steel for deep drawing and a production process thereof.
Background
The ultra-low carbon steel of the present invention is also called as ingot iron because the carbon content is below 0.04%.
The industrial pure iron product has the advantages of stable components, low harmful elements, high steel purity, high surface quality, high geometric dimension precision, good electromagnetic performance and the like, and meanwhile, the industrial pure iron product has soft material and excellent toughness and can be punched into extremely complex shapes.
At present, the ultra-low carbon industrial pure iron mainly has the following uses: the raw material is pure iron, and the main brands are YT0 and YT01 which are used for low-carbon stainless steel, precision casting, high-temperature alloy, amorphous nanocrystalline, iron-based alloy, magnetic steel and the like; the electromagnetic materials are mainly made of DT4A, DT4C, DT4E and the like, and are used for manufacturing electromagnetic elements, electromagnetic iron cores and the like in the industries of electric appliances, telecommunication, instruments, sensors, automobile brakes, national defense and the like; the cable material, the main steel trade mark has DL05, DL06, etc., this kind of steel wire rod is mainly used for communication line, television cable conductor after processing into the copper-clad steel wire, can be used as trolley bus, subway, railway, high carbon transmission slide wire, etc.; the deep drawing material is mainly used for stamping parts such as hollow rivets of baby carriages and cases, forging parts, special-shaped parts with large deformation, electromagnetic valve gaskets and other electronic elements.
The ultra-low carbon steel for deep drawing has high Al content, so the nodulation is easy to occur in the pouring process, the carbon content is difficult to control, the carbon content is high, the processing performance is easy to influence, and how to improve the molten steel castability, the deep drawing processing performance and the strength of the ultra-low carbon steel for deep drawing becomes a great difficulty in the industry.
Disclosure of Invention
The invention aims to provide a smelting process of ultra-low carbon steel for deep drawing, which adopts a process route of converter smelting → RH refining → LF furnace refining → continuous casting machine pouring → rolling by a rolling mill, can improve the castability of molten steel, saves the step of RH oxygen blowing and C removal, effectively prevents the over-high carbon content through the process control of carbon, improves the castability and the deep drawing performance, and further improves the material strength and the deep drawing performance through the reasonable addition of Al and Ti elements.
The purpose of the invention is realized by the following technical scheme:
an ultra-low carbon steel for deep drawing and a production process thereof, wherein the ultra-low carbon steel comprises the following components in percentage by weight: less than or equal to 0.010 percent of C, less than or equal to 0.08 percent of Si, less than or equal to 0.20 percent of Mn, less than or equal to 0.025 percent of P, less than or equal to 0.020 percent of S, more than or equal to 0.020 percent of Al, 0.050 to 0.120 percent of Ti, and the balance of Fe and inevitable impurities.
Further preferably, the ultra-low carbon steel comprises the following components in percentage by weight: less than or equal to 0.008 percent of C, less than or equal to 0.04 percent of Si, less than or equal to 0.15 percent of Mn, less than or equal to 0.015 percent of P, less than or equal to 0.012 percent of S, 0.052-0.075 percent of Al, 0.072-0.092 percent of Ti, and the balance of Fe and inevitable impurities.
A production process of ultra-low carbon steel for deep drawing is characterized in that: the process comprises the working procedures of converter smelting, RH refining, LF refining, soft blowing process, continuous casting and rolling, and the process flow is as follows:
(1) smelting in a converter:
the 120t converter smelting steel material adopts molten iron (the molten iron accounts for 85-90%) and high-quality scrap steel (the scrap steel accounts for 10-15%) with the S of less than or equal to 0.028%, and the converter smelting process adopts whole-process bottom blowing argon gas; controlling the carbon content at the end point of the converter to be less than or equal to 0.04 percent and the P to be less than or equal to 0.015 percent; the tapping temperature is more than or equal to 1650 ℃, oxygen is determined before tapping, the oxygen content of the target tapping is 550-650 ppm, 300 kg of composite refining slag is added into each furnace in the tapping process, and the steel slag is mixed and rushed to remove S.
Further preferably: preparing a ladle before smelting: the ladle with high carbon (C is more than 0.60 percent) and high silicon (Si is more than 0.25 percent) produced in the last furnace cannot be used for the steel grade, and residual steel residues must be cleaned before the ladle is used.
(2) RH refining:
after tapping of the converter, the molten steel is quickly hoisted to an RH station for relevant treatment, oxygen determination is carried out on the molten steel after the molten steel enters RH, then vacuumizing and natural decarburization are started, temperature measurement sampling and oxygen determination are carried out after the decarburization is finished, and all pumps are started to reach the ultimate vacuum degree (the requirement is less than or equal to 67 Pa).
RH deoxidation control: after the carbon is in the required range (C is less than or equal to 0.007 percent) after the decarburization is finished, Al is added for deoxidation according to the oxygen content of molten steel, and the oxygen content of a finished product is ensured to be less than or equal to 30ppm according to 50ppm of deoxidation of 10 kg of aluminum particles.
Controlling RH alloy aluminum: after deoxidation, the aluminum content of the alloy is adjusted to be 0.075 percent, the aluminum content is increased by 0.001 percent according to 1.3kg of aluminum particle molten steel (aluminum loss in the subsequent LF and the steel casting process needs to be considered), the main purpose of adding Al is to combine with N in the molten steel to generate small-particle AlN, so that the nitrogen fixation purpose is achieved, a large amount of TiN impurities are prevented from being produced by adding Ti subsequently, and the AlN can also achieve the purpose of refining crystal particles.
Controlling the content of RH titanium: adding 3.5-4.2kg/t ferrotitanium after the aluminum particles are added for 2 minutes and the aluminum is adjusted in place (the ferrotitanium of the first furnace is added according to the middle limit and the upper limit of the specified range); after alloying, at least circulating for 2-5 minutes and then sampling; the purpose of adding titanium to the steel grade can also achieve the purpose of dispersion strengthening besides grain refinement, and in addition, the pure degassing time under high vacuum degree (less than or equal to 67Pa) is ensured to be more than 5 minutes.
The invention provides the method that the aluminum is added firstly and then the Ti is added, so that the effect of grain refinement can be achieved, a large amount of TiN inclusions produced by subsequently adding the Ti can be prevented, the yield of the Ti is improved, and the yield of the Ti is reduced if the Ti is added at the same time, so that the effect of grain refinement is influenced.
(3) LF refining:
200 kg of lime is added in the early stage of LF refining, the whole refining process mainly adopts temperature rise (the temperature rises to 1580-. And (3) feeding an Al wire and adding a proper amount of ferrotitanium (aluminum must be added first and then Ti must be added) in sequence 10 minutes before LF is taken out according to the content conditions of Al and Ti in molten steel.
(4) The soft blowing process comprises the following steps:
the pure calcium wire is fed into the open casting furnace of 400-450 m/furnace before soft blowing, and the continuous casting furnace of 300-350 m/furnace, mainly because the open casting furnace has larger aluminum loss and more generated aluminum oxide inclusions, more pure calcium wires need to be fed to carry out denaturation treatment on the aluminum oxide inclusions so as to be removed, and the soft blowing time is required to be more than 20 min.
(5) The continuous casting process comprises the following steps:
and protective pouring is adopted in the whole continuous casting process. In order to prevent recarburization of molten steel in the continuous casting production process, the tundish adopts a special low-silicon low-carbon steel carbon-free covering agent, and has the effects of preserving heat and preventing air suction, and the physical and chemical indexes are shown in table 1; the continuous casting crystallizer uses the special ultra-low carbon steel covering slag, and the physical and chemical indexes are shown in table 2. The continuous casting secondary cooling adopts a weak cooling gas spray water distribution mode, and the specific water amount of the secondary cooling is 0.60L/min. In order to prevent slag from being discharged and improve the purity of molten steel, steel retaining operation is carried out in ladle pouring, and slag discharging is strictly forbidden (steel retaining is 3-5 tons/furnace).
TABLE 1 main indexes of special carbon-free covering agent for low-silicon and low-carbon steel
TABLE 2 main indices of ultra-low carbon steel mold flux
(6) Rolling process
The steel rolling adopts low-temperature rolling temperature, and the initial rolling temperature is controlled to be 910 +/-20 ℃; the finishing temperature is controlled to be 880 +/-20 ℃, and the phenomenon that the rolled material is soft and the surface is scratched due to overhigh temperature in the rolling process is avoided.
The invention has the beneficial effects that: considering the high requirements on carbon content, molten steel purity, deep drawing performance and strength. The invention makes the following efforts:
the oxygen content of the discharged steel of the converter is controlled to be 550-650 PPm, the oxygen remaining amount is obtained by carefully calculating the characteristics of the steel, natural decarburization of molten steel is carried out in the RH vacuum treatment process by utilizing the oxygen content, the traditional RH process oxygen blowing decarburization is avoided, an RH oxygen blowing process is omitted, the subsequent deoxidation burden caused by a large amount of oxygen blowing in the RH process is reduced, the purity of the molten steel can be effectively improved, the nodulation of subsequent steel pouring can be prevented, the number of continuous casting furnaces is increased, and the production efficiency is greatly improved.
Secondly, by controlling the use of a steel ladle, a special carbon-free covering agent and extra-low carbon steel special crystallizer covering slag are used in the continuous casting process, and the components of the carbon-free covering agent and the special covering slag are uniquely designed according to the characteristics of the steel, so that the aims of effectively controlling carbon and improving the deep drawing performance are fulfilled.
And thirdly, adding a proper amount of Al and Ti elements, and selecting a reasonable adding sequence, so that the Al has the effects of nitrogen fixation and grain refinement, the deep drawing performance is effectively improved, TiN inclusions are prevented, the added Ti can be fully combined with residual C elements in the molten steel, and the dispersion strengthening effect is realized. And aluminum and Ti are reasonably added, so that the castability of the molten steel is improved, and nodulation is prevented.
Through the efforts, the comprehensive performance of the material is effectively improved while the production efficiency is improved.
Detailed Description
Examples 1 to 3 were produced according to the chemical composition of ultra low carbon steel for deep drawing in table 3 by the process route of "converter smelting → RH furnace refining → LF furnace refining → soft blowing → continuous caster pouring → rolling", and the production control method thereof was as follows.
Example 1
(1) Converter process
1. The steel ladle is selected as the steel ladle for producing SWRCH22A (with carbon content of 0.18-0.20% and silicon content of 0.04-0.06%) in the upper furnace.
2. The loading amount of a converter with a nominal volume of 120 tons is 134.8-135.9 tons, wherein molten iron is 120.5-121.3 tons (the sulfur content of the molten iron is 0.24-0.26%), scrap steel is 14.5-15.1 tons, the tapping amount is 120.3-121.2 tons, the tapping temperature is 1655 ℃, tapping P is 0.009%, tapping sulfur is 0.018%, tapping C is 0.032%, tapping oxygen is 550-650 ppm, and 300 kg of composite refining slag is added in the tapping process.
(2) RH refining furnace process
1. RH circulation time is 15min, after vacuumizing for about 4min27S-4min35S, decarburization is started to be finished about 7min18S-7min32S, the tail gas CO content is pumped to be lower than 5% in about 10min, the tail gas is gradually pumped to a B1 pump and circulated to be broken in 15min-15min25S, carbon content is 0.0018% through spectral analysis, and oxygen is determined to be 214.6PPm at the same time.
2. And (3) after the vacuum is broken, adding 50 kg of aluminum particles for deoxidation, then adding 110 kg of aluminum particles for increasing aluminum in the molten steel, adding 500 kg of ferrotitanium after 2 minutes, then vacuumizing to 33Pa, and then keeping the vacuum degree at the ultimate vacuum degree for 5 minutes, 19 seconds to 5 minutes and 45 seconds.
(3) LF refining furnace process and soft blowing process
1. At the early stage of LF refining, 200 kg of lime is added, 20 kg of aluminum particles are used for slag surface deoxidation, the component temperature meets the requirements after the power is supplied for 20 minutes, at the moment, a 450 m pure calcium wire is fed to carry out calcium treatment on molten steel, and then the ladle is hung into a soft argon blowing table for soft blowing for 25 minutes.
(4) Continuous casting process
1. Argon blowing protection is carried out on the tundish before casting, and argon blowing protection casting is carried out on the ladle long nozzle in the whole casting process to prevent secondary oxidation of molten steel.
2. The middle part is covered by a carbon-free covering agent (table 1), and special low-silicon and low-carbon steel covering slag (table 2) is added into a crystallizer.
3. And 3.3-3.8 tons of residual molten steel in the ladle are weighed after the pouring is finished.
(5) Rolling process
The initial rolling temperature is 915 ℃, the final rolling temperature is 892 ℃, and the phi 14mm round steel is obtained by rolling.
Example 2
(1) Converter process
The tapping temperature is 1658 ℃, the tapping P is 0.008%, the tapping sulfur is 0.017%, the tapping C is 0.034%, and the tapping oxygen is 550-650 PPm, and the rest is the same as in example 1.
(2) RH refining furnace process
53 kg of aluminum shot was added for deoxidation after the vacuum break, 112 kg of aluminum shot was subsequently added for the aluminum increase of the molten steel, 505 kg of ferrotitanium was added after 2 minutes, and then vacuum was applied to 40Pa, and the ultimate vacuum was maintained for 5 minutes and 45 seconds, and the rest of the procedure was the same as in example 1.
(3) LF refining furnace Process, Soft blowing Process, same as example 1
(4) Continuous casting Process, same as example 1
(5) The rolling process comprises the following steps: the initial rolling temperature is 910 ℃, the final rolling temperature is 880 ℃, and the round steel with the diameter of 14mm is obtained by rolling.
Example 3
(1) Converter process
The tapping temperature is 1657 ℃, the tapping P is 0.010%, the tapping sulfur is 0.020%, the tapping C is 0.034%, and the tapping oxygen is 550-650 PPm, the rest is the same as in example 1.
(2) RH refining furnace process
53 kg of aluminum shot was added for deoxidation after the vacuum was broken, 115 kg of aluminum shot was subsequently added for the aluminum increase of the molten steel, 512 kg of ferrotitanium was added after 2 minutes, and then vacuum was applied to 42Pa, and the ultimate vacuum was maintained for 5 minutes and 45 seconds, as in example 1.
(3) LF refining furnace Process, Soft blowing Process, same as example 1
(4) Continuous casting Process, same as example 1
(5) The rolling process comprises the following steps: the initial rolling temperature is 915 ℃, the final rolling temperature is 870 ℃, and the phi 14mm round steel is obtained by rolling.
TABLE 3
Comparative example 1
Comparative example 1 is different from example 1 in that: the oxygen content of the converter tapping process in example 1 was not controlled, oxygen blowing and decarburization were carried out in the RH process, and other operations were the same as in example 1 to prepare ultra-low carbon steel having similar composition.
The RH oxygen blowing decarburization is adopted, so that a process is added, the cost is increased, the aluminum loss is increased in the operation process, the enrichment of a water gap is increased, the purity of molten steel is poor, and the deep drawing performance is influenced.
Comparative example 2
Comparative example 2 differs from example 1 in that: the carbon-free covering agent special for low-silicon low-carbon steel and the covering slag special for ultra-low steel adopted in the example 1 are changed into the conventional covering agent (sold in the market) and the conventional covering slag (sold in the market), and the other operations are the same as the example 1.
Comparative example 3
Comparative example 3 differs from example 1 in that: the aluminum particles and the ferrotitanium were added simultaneously to RH, and the contents of aluminum and titanium were controlled by the same procedure as in example 1.
The method specifically comprises the following steps:
and (3) after the air is broken, adding 50 kg of aluminum particles for deoxidation, then adding 110 kg of aluminum particles and 500 kg of ferrotitanium to adjust the content of aluminum and titanium, then vacuumizing to 33Pa, and then keeping the vacuum degree at the ultimate vacuum degree for 5 minutes, 19 seconds to 5 minutes and 45 seconds.
Comparative example 3 adding Al and Ti simultaneously not only affects the effect of refining grains, but also reduces the yield of Ti, and affects the deep drawing performance (cold upsetting qualification rate) and the castability of molten steel, and the casting nodulation is increased.
Comparative example 4
Comparative example 4 is different from example 1 in that: in the converter smelting step, the oxygen content of the tapped steel was determined to be 400ppm, and the other operations were the same as in example 1.
In the invention, the oxygen content is less than 550ppm, which is not only unfavorable for natural decarburization, but also influences the purity of molten steel and has adverse influence on subsequent casting nodulation and the like.
The relevant indexes of the invention in examples 1-3 and comparative examples 1-4 are compared as follows:
(1) the casting properties and deep-drawing properties are compared in Table 3 below:
TABLE 3
1/4 the detection standard of the cold upsetting qualification rate is YB/T5293 metal material upsetting test method.
(2) The nonmetallic inclusions are as follows in table 4:
TABLE 4
| Number plate | Coarse A | A is thin | B coarse | B is thin | Coarse fraction of C | Fine diameter of C | D coarse | D is thin |
| Example 1 | 0.5 | 1.0 | 0 | 0 | 0 | 0 | 0 | 0.5 |
| Comparative example 1 | 1.0 | 1.5 | 1.0 | 1.5 | 0 | 0 | 0.5 | 1.0 |
| Comparative example 2 | 0.5 | 1.0 | 0.5 | 1.0 | 0 | 0 | 0.5 | 0.5 |
| Comparative example 3 | 1.0 | 1.0 | 0.5 | 1.5 | 0 | 0 | 0.5 | 1.5 |
The detection standard and method for non-metallic inclusions are as follows: determination of non-metallic inclusion content in GB/T10561 steel-microscopic inspection method of standard rating chart.
The grain size detection method comprises the following steps: GB/T6394 metal average grain size evaluation method.
The tensile strength detection method comprises the following steps: part 1 of the tensile test of GB/T228.1 metallic Material: room temperature test method.
The results show that: in the embodiment 1, the carbon is lowest, the enrichment at the water gap after the pouring is finished is lowest, the molten steel is purest, the grade of non-metallic inclusions is lowest, and the grain size is optimal, so that the 1/4 cold upsetting yield reflecting the deep drawing processing performance of the steel is also highest.
The raw materials and equipment used in the invention are common raw materials and equipment in the field if not specified; the methods used in the present invention are conventional in the art unless otherwise specified. The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all modifications of the above embodiments made according to the technical spirit of the present invention are included in the scope of the present invention.
Claims (9)
1. The ultra-low carbon steel for deep drawing is characterized by comprising the following components in percentage by weight: less than or equal to 0.010 percent of C, less than or equal to 0.08 percent of Si, less than or equal to 0.20 percent of Mn, less than or equal to 0.025 percent of P, less than or equal to 0.020 percent of S, more than or equal to 0.020 percent of Al, 0.050 to 0.120 percent of Ti, and the balance of Fe and inevitable impurities.
2. The ultra-low carbon steel for deep drawing of claim 1, wherein the ultra-low carbon steel comprises the following components in percentage by weight: less than or equal to 0.008 percent of C, less than or equal to 0.04 percent of Si, less than or equal to 0.15 percent of Mn, less than or equal to 0.015 percent of P, less than or equal to 0.012 percent of S, 0.052-0.075 percent of Al, 0.072-0.092 percent of Ti, and the balance of Fe and inevitable impurities.
3. A process for producing the ultra low carbon steel for deep drawing according to claim 1 or 2, wherein: the production process comprises the following working procedures of converter smelting, RH refining, LF refining, soft blowing process, continuous casting and rolling:
(1) smelting in a converter:
the converter smelting iron and steel material adopts 85-90% of low-sulfur molten iron and 10-15% of scrap steel, and the converter smelting process adopts whole-process bottom blowing argon; controlling the carbon content at the end point of the converter to be less than or equal to 0.04 percent and the P to be less than or equal to 0.015 percent; the tapping temperature is more than or equal to 1650 ℃, oxygen is determined before tapping, the oxygen content of the tapping is controlled, and composite refining slag is added for desulfurization in the tapping process;
(2) RH refining:
after tapping of the converter, quickly hoisting the molten steel to an RH station, then starting vacuumizing for natural decarburization, carrying out temperature measurement sampling and oxygen determination after decarburization is finished, and completely starting a pump for vacuumizing to reach a limit vacuum degree, wherein the vacuum degree is less than or equal to 67 Pa;
RH aluminum deoxidation is carried out, and then the contents of aluminum and titanium are controlled in sequence;
(3) LF refining:
performing slag surface deoxidation by using aluminum particles in LF refining, and sequentially feeding Al wires and ferrotitanium according to the sequence of adding Al and Ti after adding Al before LF according to the content of Al and Ti in molten steel;
(4) the soft blowing process comprises the following steps:
feeding pure calcium wires before soft blowing, wherein the soft blowing time is required to be more than 20 min;
(5) and (3) continuous casting process:
the whole continuous casting process adopts protective pouring, and the tundish adopts a special carbon-free covering agent for low-silicon low-carbon steel; the continuous casting crystallizer uses ultra-low carbon steel special covering slag;
(6) a rolling procedure:
and the steel rolling adopts low-temperature rolling.
4. The process for producing an ultra-low carbon steel for deep drawing according to claim 3, wherein the low sulfur molten iron used in the smelting in the step (1) is required to have a sulfur content of not more than 0.028%; and oxygen is determined before tapping, the target tapping oxygen content is controlled to be 550-650 ppm, and 300 kg of composite refining slag is added into each furnace.
5. The process for producing ultra low carbon steel for deep drawing according to claim 3, wherein the RH deoxidation aluminum control of the step (2): after the decarburization is finished, Al is added for deoxidation according to the oxygen content of molten steel, and the deoxidation is carried out according to 50ppm of 10 kg of aluminum particles;
controlling the aluminum and titanium contents of the RH alloy: adding aluminum particles to adjust the aluminum content after the deoxidation is finished; after the aluminum content is adjusted to the right position, adding ferrotitanium for alloying, wherein the adding amount of the ferrotitanium is 3.5-4.2 kg/t; then pure degassing is carried out under the condition that the vacuum degree is less than or equal to 67Pa, and the degassing time is more than 5 minutes.
6. A process for producing ultra-low-carbon steel for deep drawing according to claim 3, wherein the steel-retained step (5) is carried out for preventing slag from falling and improving the purity of molten steel, and the retained steel is retained by 3 to 5 tons/furnace.
7. The process for producing ultra-low carbon steel for deep drawing according to claim 3, wherein the carbon-free covering agent special for low-silicon low-carbon steel and the requirements for performance indexes in the step (5) of continuous casting are as follows:
MgO≤16％、Al2O3≤18％、H2o is less than or equal to 0.5 percent, free carbon is less than or equal to 0.8 percent, CaO/SiO2：1.00～1.70、TFe≤1.3％、
Melting point: 1350-1450 deg.c and granularity not more than 1.8 mm.
8. The process for producing an ultra-low carbon steel for deep drawing according to claim 3, wherein the special mold flux for the ultra-low carbon steel and the requirements for performance indexes in the continuous casting step of the step (5) are as follows:
SiO2 40±3％、CaO 32±3％、Al2O3 6.5±1.5％、FeO≤3.0％、MgO≤4.0％、F- 5.5±2.0％、Na2O≤4.0％、FC 4.5±1.5％；CaO/SiO2: 0.8 ± 0.05, melting point: 1200. + -. 20 ℃ and viscosity (Pa.S/1300 ℃): 0.65 + -0.15.
9. The process for producing ultra-low carbon steel for deep drawing according to claim 3, wherein the low temperature rolling in the step (6) is performed by controlling the start rolling temperature to 910 ± 20 ℃; the finishing temperature is controlled to be 880 +/-20 ℃.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111876669A (en) * | 2020-06-29 | 2020-11-03 | 阳春新钢铁有限责任公司 | Control method of process for smelting low-carbon steel by converter |
| CN112593142A (en) * | 2020-10-26 | 2021-04-02 | 邯郸钢铁集团有限责任公司 | Low-cost high-purity ultra-low carbon steel strip and production method thereof |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103627853A (en) * | 2013-12-05 | 2014-03-12 | 广东韶钢松山股份有限公司 | Method for manufacturing low-carbon and low-silicon steel |
| CN106834914A (en) * | 2016-12-06 | 2017-06-13 | 内蒙古包钢钢联股份有限公司 | Deep-draw level Ti IF cold-rolled steel sheets and preparation method thereof |
| 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 |
| CN110004366A (en) * | 2019-04-23 | 2019-07-12 | 中天钢铁集团有限公司 | A kind of aluminiferous low-carbon construction(al)steel and its smelting process |
| CN110055375A (en) * | 2019-04-23 | 2019-07-26 | 南京钢铁股份有限公司 | A kind of Ultra-low carbon ultralow-sulfur steel smelting process |
-
2019
- 2019-10-17 CN CN201910988820.9A patent/CN110643887A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103627853A (en) * | 2013-12-05 | 2014-03-12 | 广东韶钢松山股份有限公司 | Method for manufacturing low-carbon and low-silicon steel |
| CN106834914A (en) * | 2016-12-06 | 2017-06-13 | 内蒙古包钢钢联股份有限公司 | Deep-draw level Ti IF cold-rolled steel sheets and preparation method thereof |
| 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 |
| CN110004366A (en) * | 2019-04-23 | 2019-07-12 | 中天钢铁集团有限公司 | A kind of aluminiferous low-carbon construction(al)steel and its smelting process |
| CN110055375A (en) * | 2019-04-23 | 2019-07-26 | 南京钢铁股份有限公司 | A kind of Ultra-low carbon ultralow-sulfur steel smelting process |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111876669A (en) * | 2020-06-29 | 2020-11-03 | 阳春新钢铁有限责任公司 | Control method of process for smelting low-carbon steel by converter |
| CN112593142A (en) * | 2020-10-26 | 2021-04-02 | 邯郸钢铁集团有限责任公司 | Low-cost high-purity ultra-low carbon steel strip and production method thereof |
| CN113073268A (en) * | 2021-03-29 | 2021-07-06 | 江苏省沙钢钢铁研究院有限公司 | Wire rod for copper-clad steel wire and production method thereof |
| CN113637887A (en) * | 2021-07-29 | 2021-11-12 | 南京钢铁股份有限公司 | Preparation method of low-carbon low-oxygen-level sulfur free-cutting steel |
| CN114622129A (en) * | 2022-03-18 | 2022-06-14 | 安阳钢铁集团有限责任公司 | Production method for preparing ultralow-carbon low-aluminum high-silicon steel by LF + RH duplex method |
| CN114892066A (en) * | 2022-05-21 | 2022-08-12 | 湖南华菱湘潭钢铁有限公司 | Production method of steel for low-carbon electrode |
| CN114892066B (en) * | 2022-05-21 | 2023-09-05 | 湖南华菱湘潭钢铁有限公司 | Production method of steel for low-carbon electrode |
| CN116411226A (en) * | 2023-04-17 | 2023-07-11 | 福建三宝钢铁有限公司 | Ultra-low carbon flexible wire steel SWRM6 and preparation method thereof |
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