[go: up one dir, main page]

WO2023093112A1 - Procédé de fusion et de coulée continue pour acier à haute teneur en cr-si allié à chaud - Google Patents

Procédé de fusion et de coulée continue pour acier à haute teneur en cr-si allié à chaud Download PDF

Info

Publication number
WO2023093112A1
WO2023093112A1 PCT/CN2022/109343 CN2022109343W WO2023093112A1 WO 2023093112 A1 WO2023093112 A1 WO 2023093112A1 CN 2022109343 W CN2022109343 W CN 2022109343W WO 2023093112 A1 WO2023093112 A1 WO 2023093112A1
Authority
WO
WIPO (PCT)
Prior art keywords
alloying
alloy
continuous casting
smelting
steel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2022/109343
Other languages
English (en)
Chinese (zh)
Inventor
徐伟
王鲁宁
王飞
胡军
杨得草
王灵禺
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bengang Steel Plates Co Ltd
Northeastern University China
Original Assignee
Bengang Steel Plates Co Ltd
Northeastern University China
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from CN202111438770.0A external-priority patent/CN113857448B/zh
Priority claimed from CN202111438757.5A external-priority patent/CN114032473B/zh
Application filed by Bengang Steel Plates Co Ltd, Northeastern University China filed Critical Bengang Steel Plates Co Ltd
Publication of WO2023093112A1 publication Critical patent/WO2023093112A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • 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
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/20—Ferrous alloys, e.g. steel alloys containing chromium with copper
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum

Definitions

  • the invention belongs to the technical field of iron and steel smelting and casting, and in particular relates to a method for smelting and continuous casting of high-Cr-Si alloyed hot-formed steel.
  • the coated hot-formed steel also has the problems of cold rolling in the rolling process, and the coating has problems such as sticking to the roll during the rolling process.
  • a coating-free hot-forming high-strength steel is proposed, with carbon content ⁇ 0.3%, silicon ⁇ 0.8%, manganese content ⁇ 0.8%, chromium content ⁇ 1.5%, and a certain amount of Ni, Nb, Ti and other microalloying elements.
  • the high Cr-Si alloying enables this hot-formed steel to reduce the scale formed by surface oxidation, thereby eliminating the aluminum-silicon coating commonly used in existing hot-formed steels.
  • the composition of this coating-free high Cr-Si hot forming steel contains relatively large amounts of silicon, manganese and chromium alloys, the total amount of alloys is about 9-18 tons (per 180 tons of molten steel), and the proportion of alloys can reach 5-10%. .
  • the alloy is added during the smelting process during the tapping process of the converter, and is added along with the tapping flow. In order to ensure the uniformity of alloying, alloy addition usually requires deoxidation alloying to start when 1/5 of the steel is tapped from the converter, and the addition is completed when 2/3 of the steel is tapped.
  • Chinese patent CN10540440A provides a method for adding alloys to medium and high manganese alloy steels for converter smelting, the method is aimed at medium and high manganese steels, medium manganese steel with Mn content of 3.0%-6.0% and high manganese with Mn ⁇ 6.0% Steel, this method adds alloys before tapping or in the converter to solve the problem of adding a large amount of alloys, but adding alloys to large tanks (ladles) before tapping will affect the ventilation effect of the ladle vent bricks, resulting in the ladle not being able to blow argon at the bottom gas; adding the alloy in the converter affects the yield of the alloy and the cost is high.
  • mold slag added to the mold should evenly transfer heat to the slab and reduce the friction between the mold and the slab. Improve the surface quality of continuous casting slabs, and at the same time absorb inclusions to prevent secondary oxidation and heat preservation of molten steel. If the mold slag has poor performance, it will flow into the air gap unevenly, resulting in uneven heat transfer. Under the action of internal stress and friction in the mold, more microcracks and longitudinal cracks will appear on the surface of the continuous casting slab.
  • the high Cr-Si alloying of the above-mentioned coating-free hot-forming steel will increase the strength of the steel, increase the hardenability, and cause a large shrinkage during the solidification process.
  • the slab shell is not uniform, and the performance of the existing continuous casting mold flux can hardly fully meet the use requirements of this steel type.
  • the invention provides a smelting and continuous casting method for high Cr-Si alloyed hot forming steel.
  • smelting process in view of the large amount of alloys containing silicon, manganese and chromium required for this type of steel, by reasonably matching the two methods of adding alloys in the ladle and adding alloys in the refining LF furnace for steelmaking, accurate control is achieved.
  • the high Cr-Si hot forming steel of the present invention has the following specific components (by mass fraction): C: 0.15-0.35%, Mn: 0.8-3.2%, Si: 0.8-2.8%, S: ⁇ 0.01%, P: ⁇ 0.015%, Al: 0.01-0.05%, Cr: 1.5-3.9%, and one or several microalloying elements such as Nb, V, Ti, Cu, etc., if the composition contains these microalloying elements, The contents are: Nb: 0.01-0.05%, V: 0.01-0.05%, Ti: 0.01-0.03%, Cu: 0.05-0.15%, and the balance is Fe and other unavoidable impurities.
  • the production process of steel grades is converter smelting-converter tapping-ladle refining furnace LF-continuous casting (LD-LF-CC).
  • the smelting and continuous casting methods of the high Cr-Si hot-formed steel are as follows:
  • Step 1 Preparation before tapping: Carry out converter steelmaking. No alloy elements are added during the converter steelmaking process. Open the ladle under the furnace within 5-8 minutes before tapping the converter, open the ladle, and blow argon to the bottom of the ladle. The bottom argon blowing operation must be carried out throughout the tapping process, and the bottom blowing argon can not be completely closed until the steel is tapped to throw the slag dart or judge the clearance. When tapping, it is necessary to add refining slag and lime to the converter under the condition of bottom blowing argon.
  • Step 2 Primary alloying: start tapping, and carry out deoxidation alloying in the converter during the tapping process.
  • the method is to add deoxidizer-aluminum balls or aluminum particles-silicon alloy-manganese in sequence in the order of first strong and then weak Alloys - Chromium-based alloys.
  • the deoxidation alloying starts when the converter taps 1/5 of the steel into the ladle, and finishes adding 2/3 of the time.
  • These materials for deoxidation alloying can be added in batches with the steel flow, and the material added in each batch is 5-18kg/ton of molten steel, and the interval between batches is 1-2min until the planned alloy addition amount is completed.
  • the deoxidation alloying is carried out for about 50- 80% silicon alloying, 85-90% manganese alloying and 25-75% chromium alloying process.
  • the entire alloying process is completed in the deoxidation alloying stage.
  • the formula for calculating the amount of alloy added is: alloying ratio * target value of composition / (proportion of alloy element content in the added alloy * alloy yield). Alloying in the deoxidation alloying stage is called primary alloying process.
  • Step 3 After tapping the converter, add lime and top slag modifier to the ladle for top slag modification.
  • Step 4 Carry out the refining LF process.
  • refining LF In the process of refining LF, add silicon alloys, manganese alloys, and chromium alloys for secondary alloying.
  • silicon alloys, manganese alloys In the secondary alloying, silicon alloys, manganese alloys, There is no fixed order for the addition of chromium alloys. Secondary alloying requires Si, Mn, and Cr elements to complete the alloying requirements of the remaining parts.
  • the calculation formula for alloy addition can also refer to the above "alloying ratio * target value of components / (in the alloy Alloy element content ratio * alloy yield)", except that the alloying ratio used here is 1 minus the alloying ratio of the first alloying.
  • the conventional refining LF process will carry out slagging and desulfurization, which also helps to improve the yield of each alloy.
  • Step 5 Alloy fine-tuning: Carry out alloy fine-tuning, carry out alloying of carbon according to the change of carbon, and complete the smelting process of the alloy to be prepared. Carbon alloying can be carried out with carburizers.
  • the silicon-based alloy used for primary alloying can be ferrosilicon
  • the manganese-based alloy can be medium-carbon ferromanganese
  • the chromium-based alloy can be high-carbon ferrochromium
  • the silicon-based alloy used for secondary alloying can be ferrosilicon
  • the manganese alloy can be high carbon ferromanganese
  • the chromium alloy can be high carbon ferrochromium
  • the composition also includes micro-alloying elements Nb, V, Ti, Cu, etc., Nb, V, and Ti are more expensive, and they need to be added after the addition of silicon-based alloys, manganese-based alloys, and chromium-based alloys during the secondary alloying process, respectively. It is added in the form of ferro-niobium, ferro-vanadium and ferro-titanium. Cu can be added through metal copper, because it is not easy to be oxidized, it can be added at any time, such as adding during primary alloying or secondary alloying, or directly into the converter when tapping. These microalloys need to be added in a low amount, and can complete 100% alloying at one time.
  • Step 6 Alloy continuous casting: the smelted alloy is used for continuous casting to produce a continuous casting slab of the hot-formed steel.
  • the following low-alkalinity continuous casting mold flux can be used: CaO, 30-40%; SiO 2 , 40%-50%; MgO, 2-3%; Al 2 O 3 , 0.1- 1.0%; Fe 2 O 3 ⁇ 2.0%; MnO, 3 ⁇ 7%; Na 2 O, 5 ⁇ 12%; K 2 O, 0.1 ⁇ 1.0%; CaF 2 , 0 ⁇ 2%; C, 0 ⁇ 3% .
  • the continuous casting mold flux can be prepared by the following method:
  • the mold powder is produced by the pre-melting method, and the industrial materials such as wollastonite, quartz sand, soda, fluorite and other industrial materials used to make the mold powder are weighed according to the mass percentage of the design target composition; the weighed raw materials are mixed and mechanically stirred , so that the ingredients are mixed evenly; the mixed samples are made into blocks or balls and dried, then poured into a crucible and placed in a heating furnace such as an intermediate frequency induction furnace to heat and melt.
  • the industrial materials such as wollastonite, quartz sand, soda, fluorite and other industrial materials used to make the mold powder are weighed according to the mass percentage of the design target composition
  • the weighed raw materials are mixed and mechanically stirred , so that the ingredients are mixed evenly
  • the mixed samples are made into blocks or balls and dried, then poured into a crucible and placed in a heating furnace such as an intermediate frequency induction furnace to heat and melt.
  • the steel type targeted by the present invention contains relatively high alloying elements such as carbon, silicon, and chromium, and has unique solidification characteristics.
  • the initial billet shell solidifies and shrinks greatly, and the solidification shrinkage is uneven, so that the billet shell surface There are many microcracks or longitudinal cracks.
  • the method is to use high-basic mold flux, but the slag film formed by high-basic mold flux cannot be effectively in close contact with the billet shell, and the heat transfer rate is low, and the silicon content of the steel grades targeted by the present invention High, rapid heat transfer is required in the crystallizer to form an effective shell thickness, and the heat transfer rate of mold flux with high alkalinity (CaO/SiO 2 >1.1) cannot meet the heat transfer requirements.
  • the continuous casting mold flux in order to solve the quality problems such as micro-cracks or longitudinal cracks on the surface of the slab of this steel type, it is necessary for the continuous casting mold flux to have multiple properties such as uniform heat transfer, fast and good lubrication, so as to strictly control the transfer of the slab shell in the mold.
  • Thermal uniformity in the production of high Cr-Si alloyed coating-free hot forming steel, solves the problem of surface defects in cast billets.
  • the Cr element improves the hardenability of the steel
  • Cr is a carbide forming element
  • the precipitation at the grain boundary increases the stress concentration and increases the brittle area of the steel, which requires protection
  • Slag has good lubricity, and needs to have low alkalinity, low viscosity, and the melting temperature and transition temperature should not be too high to form a sufficient liquid slag film to ensure good heat transfer and lubrication between the billet and the mold.
  • the basicity, transition temperature and melting temperature of the mold slag should not be too low, so as to form a sufficient solid slag film, so that the mold slag can inhibit heat transfer and be uniform.
  • the ability to transfer heat there are oxides such as Al 2 O 3 and Cr 2 O 3 floating in the molten steel of the steel type targeted by the present invention, which will easily cause assimilation and absorption of mold slag when they enter the slag, so the alkalinity should not be too low.
  • the heat transfer performance (including heat transfer capability and heat transfer uniformity) of the mold flux for continuous casting of the present invention should be considered, and secondly, the lubrication of the mold flux should be considered. Therefore, the basicity R of the mold flux should be strictly controlled. , melting temperature, transition temperature, viscosity and other properties are within the appropriate range:
  • the alloy is added and refined in the LF furnace when the converter is tapped
  • the alloy is added to achieve the purpose of accurately controlling the alloy composition of the coating-free hot forming steel.
  • the two processes of converter and refining LF ladle furnace are used to complete the alloying process of this steel type and optimize its alloy. Add the proportioning relationship to achieve accurate control of the ingredients of the brand. At the same time, the yield of the alloy can be improved, and the cost can be saved.
  • the present invention uses low-basicity mold flux, by adjusting the basicity and adding a certain amount of MnO and other components, to ensure good heat transfer and lubrication between the billet and the crystallizer, and at the same time It has good uniformity of heat transfer and reduces the occurrence of microcracks and longitudinal cracks on the surface of the slab. The occurrence rate of surface crack defects can be reduced from 20% before use to 2% after use.
  • the low-alkalinity mold flux proposed by the present invention has a lower fluorine content, which can meet the heat transfer and lubrication performance of crack-sensitive steel continuous casting mold flux, reduce the fluorine content in air and water, reduce pollution and reduce the impact of fluorine-containing water on equipment Corrosion, and does not use Li 2 O, B 2 O 3 and other components with high prices, the cost is low, and the cost of use is saved.
  • Fig. 1 is a photograph of the surface of a cast slab produced during continuous casting using mold flux in Comparative Example 2-1.
  • Fig. 2 is a photograph of the surface of a cast slab produced during continuous casting using mold flux in Example 6.
  • the composition of steel alloy elements in each embodiment of the present invention is shown in the table below:
  • Example 1 0.26 1.871 1.931 0.006 0.0008 2.836 0.0373 0.0421
  • Example 2 0.23 1.868 1.928 0.009 0.0006 2.818 0.0364 0.0413
  • Example 3 0.24 1.87 1.929 0.009 0.0009 2.828 0.0371 0.0416
  • the calculation method of the alloy addition amount is calculated by taking the alloying of ferrosilicon as an example:
  • the target proportion of steel silicon is 1.8%
  • the tapping amount is 175t
  • the target component value is 175 ⁇ 1000 ⁇ 1.8% kg
  • the silicon content of ferrosilicon is 76.06%
  • the alloy yield is determined to be 91.82% based on experience.
  • the composition of primary alloyed silicon is controlled to 1%, that is, the primary alloying ratio is 1/1.8:
  • the yield of secondary alloyed ferrosilicon alloy is empirically determined to be 98.8%, and the secondary alloying control silicon content is 0.8%:
  • Preparation before tapping Open the ladle under the furnace within 5-8 minutes before tapping, open the ladle, and blow the bottom argon on the ladle. Only when the bottom blowing argon can be completely closed. After tapping, add refining slag and lime to the converter under the condition of bottom blowing argon.
  • the materials used for primary alloying are: 2009kg medium carbon ferromanganese, 2504kg ferrosilicon, 181kg aluminum particles and 3014kg high carbon ferrochromium.
  • Top slag modification Lime and top slag modifier are added to the ladle after converter tapping for top slag modification. Add 500kg of lime and 400kg of top slag modifier.
  • Secondary alloying carry out the refining LF process. During the refining LF process, add 1853kg of ferrosilicon, 6523kg of high-carbon ferrochrome, 800kg of high-carbon ferromanganese, and 90kg of ferro-niobium for secondary alloying. , high-carbon ferrochromium and high-carbon ferromanganese are all added before adding, and the secondary alloying completes the alloying requirements of the remaining parts of Si, Mn, and Cr elements, and completes all the alloying requirements of Nb.
  • Alloy fine-tuning carry out alloy fine-tuning, carry out alloying of carbon according to the change of carbon, and use refined recarburizing agent, the addition amount is 138kg.
  • Alloy continuous casting the smelted alloy is used for continuous casting to make the continuous casting slab of the hot-formed steel.
  • the chemical composition of low-alkalinity coating-free mold flux used in the continuous casting process is CaO, 33.66%; SiO 2 , 44.98%; MgO, 2.56%; Al 2 O 3 , 0.68%; Fe 2 O 3 ⁇ 2.0%; MnO, 5.38%; Na2O , 9.71%; K2O , 0.38%; CaF2 , 0.96%; C, 1.26%.
  • the basicity (CaO/SiO 2 ) of the mold flux is 0.75, the hemispherical point temperature is 1148°C, and the viscosity at 1300°C is 0.59Pa ⁇ s.
  • Pre-melting method is used for the production and preparation of mold slag, and industrial materials such as wollastonite, quartz sand, soda, fluorite and other industrial materials used for making mold slag are weighed according to the mass percentage of the design target composition; the weighed raw materials are mixed and mechanically stirred , so that the ingredients are mixed evenly; the mixed samples are made into blocks or balls and dried, then poured into a crucible and placed in an intermediate frequency induction furnace, heated and melted at 1000-1500 ° C, and kept for 1-3 hours to remove volatiles and uniform slag components ; Pour molten slag into water to rapidly cool to obtain a uniform glass-like amorphous substance; dry the glass-like amorphous substance and pulverize it into powder to obtain the required mold slag powder.
  • industrial materials such as wollastonite, quartz sand, soda, fluorite and other industrial materials used for making mold slag are weighed according to the mass percentage of the design target composition; the weighed raw materials are
  • Example 2 Basically the same as Example 1, the difference is that the materials used for primary alloying are medium carbon ferromanganese 2008kg, ferrosilicon 2500kg, aluminum particles 186kg and high carbon ferrochrome 3008kg; secondary alloying (refining LF process) used The materials are 92kg of ferro-niobium, 1851kg of ferrosilicon, 6520kg of high-carbon ferrochrome, and 802kg of high-carbon ferromanganese; the refining recarburizer used for alloy fine-tuning is 136kg.
  • the materials used for primary alloying are medium carbon ferromanganese 2008kg, ferrosilicon 2500kg, aluminum particles 186kg and high carbon ferrochrome 3008kg; secondary alloying (refining LF process) used The materials are 92kg of ferro-niobium, 1851kg of ferrosilicon, 6520kg of high-carbon ferrochrome, and 802kg of high-carbon ferromanganese
  • Example 2 Substantially the same as Example 1, the difference is that the materials used for primary alloying are medium carbon ferromanganese 2006kg, ferrosilicon 2508kg, aluminum particles 182kg and high carbon ferrochrome 3012kg; secondary alloying (refining LF process) used The materials are 88kg of ferro-niobium, 1853kg of ferrosilicon, 6523kg of high-carbon ferrochrome, and 800kg of high-carbon ferromanganese; the refining recarburizer used for alloy fine-tuning is 133kg.
  • the materials used for primary alloying are medium carbon ferromanganese 2006kg, ferrosilicon 2508kg, aluminum particles 182kg and high carbon ferrochrome 3012kg; secondary alloying (refining LF process) used The materials are 88kg of ferro-niobium, 1853kg of ferrosilicon, 6523kg of high-carbon ferrochrome, and 800kg of high-carbon ferromanganes
  • Example 2 It is basically the same as Example 1, except that the alloy composition also contains 0.03% vanadium, and 103kg of ferrovanadium is added after ferroniobium.
  • Example 2 It is basically the same as Example 1, except that the content of niobium in the steel target composition is different from Example 1, and also contains other microalloying elements: Nb: 0.03%, V: 0.03%, Ti: 0.02%, Cu: 0.08 %.
  • the alloy composition used is ferroniobium containing 65.5% of niobium, ferrovanadium containing 53.29% of vanadium, ferrotitanium containing 33.6% of titanium, and copper is added in the form of copper metal containing 99.8% of copper.
  • the yield of the alloy is empirically determined to be 98.9% of ferroniobium, 95.75% of ferro-vanadium, 85.56% of ferro-titanium and 98% of copper.
  • All microalloying elements are added after the alloying of silicon, chromium, and manganese is completed in the secondary alloying process.
  • the tapping amount is 175t, and the alloying amounts are 82kg ferroniobium, 103kg ferrovanadium, 122kg ferrotitanium, and 145kg copper.
  • Example 1 The difference from Example 1 is that the alloying of all Si, Cr, and Mn elements is completed in the converter tapping process, and only the alloying of niobium and the final alloy fine-tuning are performed in the refining LF process.
  • the materials used for alloying in the converter tapping process are 3038kg of medium-carbon ferromanganese, 4668kg of ferrosilicon, 191kg of aluminum particles and 9828kg of high-carbon ferrochrome; 89kg of ferroniobium and 116kg of refined recarburizer in the refining LF process.
  • Example 1 The difference from Example 1 is that the alloying of all Si, Cr, and Mn elements is completed in the converter tapping process, and only the alloying of niobium and the final alloy fine-tuning are performed in the refining LF process.
  • the materials used for alloying in the converter tapping process are 2969kg of medium-carbon ferromanganese, 4703kg of ferrosilicon, 176kg of aluminum particles and 9719kg of high-carbon ferrochrome; 87kg of ferroniobium and 128kg of refining recarburizer in the refining LF process.
  • the method for preparing mold flux is similar to that of Example 1.
  • the chemical composition of the prepared low-alkalinity mold flux is CaO, 34.13%; SiO 2 , 47.46%; MgO, 2.12%; Al 2 O 3 , 0.58%; Fe 2 O 3 ⁇ 2.0%; MnO, 4.02%; Na2O , 9.79%; K2O , 0.45%; CaF2 , 0.83%; C, 0.61%.
  • the basicity (CaO/SiO 2 ) of the prepared mold flux is 0.72, the hemispherical point temperature is 1151°C, and the viscosity at 1300°C is 0.57Pa ⁇ s.
  • the mold slag is used for the continuous casting of high Cr-Si hot-formed steel with the following components smelted according to steps 1 to 5 of the present invention.
  • the components of the steel are: C: 0.20%, Mn: 1.5%, Si: 2.0%, S: ⁇ 0.01%, P: ⁇ 0.015%, Al: 0.03%, Cr: 2.0%, Nb: 0.01%, V: 0.05%, Ti: 0.03%, Cu: 0.15%, the balance is Fe and other unavoidable of impurities.
  • the method for preparing mold flux is similar to that of Example 1.
  • the chemical composition of the prepared low-alkalinity mold flux is CaO, 36.68%; SiO 2 , 46.85%; MgO, 2.69%; Al 2 O 3 , 0.76%; Fe 2 O 3 ⁇ 2.0%; MnO, 4.19%; Na2O , 6.9%; K2O , 0.62%; CaF2 , 0.37%; C, 0.8%.
  • the basicity (CaO/SiO 2 ) of the prepared mold flux is 0.78, the hemispherical point temperature is 1147°C, and the viscosity at 1300°C is 0.6Pa ⁇ s.
  • the mold slag is used for the continuous casting of high Cr-Si hot-formed steel with the following components smelted according to steps 1 to 5 of the present invention.
  • the components of the steel are: C: 0.15%, Mn: 3.0%, Si: 1.0%, S: ⁇ 0.01%, P: ⁇ 0.015%, Al: 0.05%, Cr: 3.5%, Nb: 0.03%, V: 0.03%, Ti: 0.02%, Cu: 0.10%, the balance is Fe and other unavoidable of impurities.
  • the method of preparing mold flux is similar to that of Example 1.
  • the chemical composition of the prepared low-alkalinity mold flux is CaO, 35.28%; SiO 2 , 44.35%; MgO, 2.64%; Al 2 O 3 , 0.69%; Fe 2 O 3 ⁇ 2.0%; MnO, 5.28%; Na2O , 9.9%; K2O , 0.53%; CaF2 , 0.63%; C, 0.7%.
  • the basicity (CaO/SiO 2 ) of the prepared mold flux is 0.80, the hemispherical point temperature is 1150°C, and the viscosity at 1300°C is 0.56Pa ⁇ s.
  • composition of the high Cr-Si hot-formed steel applied with mold flux is the same as that of Example 7.
  • the method of preparing mold flux is similar to that of Example 1.
  • the chemical composition of the prepared low-alkalinity mold flux is CaO, 33.26%; SiO 2 , 44.37%; MgO, 2.85%; Al 2 O 3 , 0.59%; Fe 2 O 3 ⁇ 2.0%; MnO, 6.36%; Na2O , 9.83%; K2O , 0.69%; CaF2 , 0.75%; C, 0.87%.
  • the basicity (CaO/SiO 2 ) of the prepared mold flux is 0.75, the hemispherical point temperature is 1149°C, and the viscosity at 1300°C is 0.58Pa ⁇ s.
  • the mold slag is used for the continuous casting of high Cr-Si hot-formed steel with the following components smelted according to steps 1 to 5 of the present invention.
  • the components of the steel are: C: 0.30%, Mn: 1.0%, Si: 2.5%, S: ⁇ 0.01%, P: ⁇ 0.015%, Al: 0.02%, Cr: 1.5%, Nb: 0.05%, V: 0.01%, Ti: 0.03%, Cu: 0.05%, the balance is Fe and other unavoidable of impurities.
  • the chemical composition is CaO, 34.17%; SiO 2 , 26.99%; MgO, 2.79%; Al 2 O 3 , 3.79%; Fe 2 O 3 ⁇ 2.0%; MnO, 5.14 %; O, 7.94%; K2O , 0.14%; CaF2 , 7.45%; C, 7.74%.
  • the basicity (CaO/SiO 2 ) of the mold flux is 1.27, the hemispherical point temperature is 1101°C, and the viscosity at 1300°C is 1.06Pa ⁇ s.
  • the high Cr-Si hot-formed steel applied with mold flux is the same as that in Example 6.
  • the chemical composition is CaO, 34.17%; SiO 2 , 26.8%; MgO, 2.63%; Al 2 O 3 , 3.89%; Fe 2 O 3 ⁇ 2.0%; MnO, 5.17 %; O, 8.06%; K2O , 0.34%; CaF2 , 7.5%; C, 7.85%.
  • the basicity (CaO/SiO 2 ) of the mold flux is 1.28
  • the hemispherical point temperature is 1103°C
  • the viscosity at 1300°C is 1.04Pa ⁇ s.
  • the high Cr-Si hot-formed steel applied with mold flux is the same as that in Example 7.
  • the chemical composition is CaO, 34.15%; SiO 2 , 26.89%; MgO, 2.69%; Al 2 O 3 , 3.86%; Fe 2 O 3 ⁇ 2.0%; MnO, 5.16%; Na 2 O, 7.98%; K2O , 0.29%; CaF2 , 7.46%; C, 7.76%.
  • the basicity (CaO/SiO 2 ) of the mold flux is 1.27
  • the hemispherical point temperature is 1102°C
  • the viscosity at 1300°C is 1.05Pa ⁇ s.
  • the high Cr-Si hot-formed steel applied with mold flux is the same as that in Example 9.
  • Comparative Examples 2-1 to 2-3 are high-alkalinity mold fluxes commonly known to reduce cracks.
  • Fig. 1 is a slab produced when using the mold flux in Comparative Example 2-1 for continuous casting
  • Fig. 2 is a slab produced when using the mold flux in Example 6 for continuous casting. It can be clearly seen that when the high-basicity mold flux that is generally known to reduce cracks in Comparative Example 2-1 is used, there are still many cracks on the surface of the slab, while the mold flux made by using the mold flux in Example 1 of the present invention The billet surface quality is better and no cracks appear.
  • the mold slags in Comparative Examples 2-1 to 2-3 are used for the coating-free hot-forming steel, and the quality of the slabs produced is poor, and the occurrence rate of surface crack defects is nearly 20%.
  • the quality of the slab is good, and the occurrence rate of surface crack defects is reduced to below 2%.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Continuous Casting (AREA)

Abstract

L'invention concerne un procédé de fusion et de coulée continue pour un acier à haute teneur en Cr-Si allié à chaud. Pendant le processus de fusion, la désoxydation et l'alliage primaire sont réalisés pendant le tirage du convertisseur afin de terminer l'alliage complet de l'Al et l'alliage partiel du Si, Mn et Cr ; et pendant le processus d'affinage LF, un alliage de silicium, un alliage de manganèse et un alliage de chrome sont ajoutés pour effectuer un alliage secondaire afin de finir l'alliage des éléments Si, Mn et Cr restants ; et lorsqu'une coulée continue est réalisée après fusion, un laitier protecteur à faible alcalinité est utilisé. Le procédé vise à résoudre le problème d'une quantité d'addition relativement grande d'alliages de silicium, de manganèse et de chrome requise par un acier, et grâce à la mise en correspondance rationnelle de deux modes d'ajout d'un alliage en poche d'acier et d'ajout d'un alliage de four LF pendant l'élaboration de l'acier au convertisseur, les composants d'alliage pour un acier formé à chaud sans revêtement sont régulés avec précision ; et pendant le processus de coulée continue, le laitier protecteur à faible alcalinité ayant un transfert de chaleur uniforme et une bonne propriété de lubrification est utilisé, de telle sorte que les problèmes de poches d'air se formant facilement et d'une écorce brute irrégulière dans l'acier sont résolus.
PCT/CN2022/109343 2021-11-29 2022-08-01 Procédé de fusion et de coulée continue pour acier à haute teneur en cr-si allié à chaud Ceased WO2023093112A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
CN202111438770.0A CN113857448B (zh) 2021-11-29 2021-11-29 一种低碱度免涂层热成形钢连铸用保护渣
CN202111438757.5A CN114032473B (zh) 2021-11-29 2021-11-29 一种免涂层热成形钢的合金加入方法
CN202111438770.0 2021-11-29
CN202111438757.5 2021-11-29

Publications (1)

Publication Number Publication Date
WO2023093112A1 true WO2023093112A1 (fr) 2023-06-01

Family

ID=86538819

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/109343 Ceased WO2023093112A1 (fr) 2021-11-29 2022-08-01 Procédé de fusion et de coulée continue pour acier à haute teneur en cr-si allié à chaud

Country Status (1)

Country Link
WO (1) WO2023093112A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116855673A (zh) * 2023-07-04 2023-10-10 南京钢铁股份有限公司 一种低碱度渣特殊钢降低渣耗和电耗的造渣工艺
CN117708708A (zh) * 2024-02-06 2024-03-15 北京科技大学 一种炼钢用铁合金的品质评级及推荐方法
CN118996288A (zh) * 2024-07-15 2024-11-22 天津水泥工业设计研究院有限公司 一种转底炉叶片用高温耐磨材料及转底炉叶片的制备方法
CN119614794A (zh) * 2024-12-20 2025-03-14 襄阳昊鑫源机械有限公司 一种基于废钢熔铸的提高铸钢强度和韧性的方法
CN120984830A (zh) * 2025-10-22 2025-11-21 东北大学 一种Cr12MoV模具钢的连铸用保护渣及其制备方法

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5085691A (en) * 1988-07-26 1992-02-04 Nakonechny Anatoly Y Method of producing general-purpose steel
CN102453831A (zh) * 2010-10-26 2012-05-16 攀钢集团钢铁钒钛股份有限公司 冶炼高铬钢的方法和高铬钢
CN102864275A (zh) * 2012-09-25 2013-01-09 鞍钢股份有限公司 一种重轨钢铝含量的控制方法
CN103642967A (zh) * 2013-11-18 2014-03-19 攀钢集团攀枝花钢铁研究院有限公司 一种转炉生产高铬钢的方法
CN104313234A (zh) * 2014-10-14 2015-01-28 武汉钢铁(集团)公司 提高贵重合金元素回收率的方法
CN104531939A (zh) * 2015-01-15 2015-04-22 唐山钢铁集团有限责任公司 一种高合金高强度钢的冶炼方法
JP2016188401A (ja) * 2015-03-30 2016-11-04 Ｊｆｅスチール株式会社 高マンガン鋼の溶製方法
CN107012287A (zh) * 2017-04-18 2017-08-04 攀钢集团攀枝花钢铁研究院有限公司 用于热冲压成型钢的冶炼方法
CN108486456A (zh) * 2018-05-09 2018-09-04 张家港荣盛炼钢有限公司 高铬耐蚀钢的冶炼方法
CN112708720A (zh) * 2020-12-10 2021-04-27 安阳钢铁股份有限公司 一种提高低碳低硅含铌钢铌收得率的冶炼方法
CN114032473A (zh) * 2021-11-29 2022-02-11 东北大学 一种免涂层热成形钢的合金加入方法

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5085691A (en) * 1988-07-26 1992-02-04 Nakonechny Anatoly Y Method of producing general-purpose steel
CN102453831A (zh) * 2010-10-26 2012-05-16 攀钢集团钢铁钒钛股份有限公司 冶炼高铬钢的方法和高铬钢
CN102864275A (zh) * 2012-09-25 2013-01-09 鞍钢股份有限公司 一种重轨钢铝含量的控制方法
CN103642967A (zh) * 2013-11-18 2014-03-19 攀钢集团攀枝花钢铁研究院有限公司 一种转炉生产高铬钢的方法
CN104313234A (zh) * 2014-10-14 2015-01-28 武汉钢铁(集团)公司 提高贵重合金元素回收率的方法
CN104531939A (zh) * 2015-01-15 2015-04-22 唐山钢铁集团有限责任公司 一种高合金高强度钢的冶炼方法
JP2016188401A (ja) * 2015-03-30 2016-11-04 Ｊｆｅスチール株式会社 高マンガン鋼の溶製方法
CN107012287A (zh) * 2017-04-18 2017-08-04 攀钢集团攀枝花钢铁研究院有限公司 用于热冲压成型钢的冶炼方法
CN108486456A (zh) * 2018-05-09 2018-09-04 张家港荣盛炼钢有限公司 高铬耐蚀钢的冶炼方法
CN112708720A (zh) * 2020-12-10 2021-04-27 安阳钢铁股份有限公司 一种提高低碳低硅含铌钢铌收得率的冶炼方法
CN114032473A (zh) * 2021-11-29 2022-02-11 东北大学 一种免涂层热成形钢的合金加入方法

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116855673A (zh) * 2023-07-04 2023-10-10 南京钢铁股份有限公司 一种低碱度渣特殊钢降低渣耗和电耗的造渣工艺
CN117708708A (zh) * 2024-02-06 2024-03-15 北京科技大学 一种炼钢用铁合金的品质评级及推荐方法
CN117708708B (zh) * 2024-02-06 2024-04-12 北京科技大学 一种炼钢用铁合金的品质评级及推荐方法
CN118996288A (zh) * 2024-07-15 2024-11-22 天津水泥工业设计研究院有限公司 一种转底炉叶片用高温耐磨材料及转底炉叶片的制备方法
CN119614794A (zh) * 2024-12-20 2025-03-14 襄阳昊鑫源机械有限公司 一种基于废钢熔铸的提高铸钢强度和韧性的方法
CN120984830A (zh) * 2025-10-22 2025-11-21 东北大学 一种Cr12MoV模具钢的连铸用保护渣及其制备方法

Similar Documents

Publication Publication Date Title
WO2023093112A1 (fr) Procédé de fusion et de coulée continue pour acier à haute teneur en cr-si allié à chaud
CN102409238B (zh) 一种42CrMo合金结构钢特厚板及其生产方法
CN102107215B (zh) 一种资源节约型含硼高速钢复合轧辊及其制备方法
CN109852891B (zh) 一种低碳含硼钢连铸板坯角部裂纹控制方法
CN106756511B (zh) 一种双金属锯条背材用d6a热轧宽带钢及其生产方法
CN104532102A (zh) 风电用大规格渗碳轴承钢G20Cr2Ni4A制造新工艺
CN108251739A (zh) 一种高强度高伸长率球墨铸铁及其制备方法
CN105458227B (zh) 离心铸造高硼高速钢复合轧辊及其制备方法
CN110230006A (zh) 一种汽车变速箱用低磷齿轮钢的生产方法
CN113528976B (zh) 一种非调质无表面裂纹棒材及其制备方法
CN118222912B (zh) 一种高品质高碳钢线材的短流程制备方法及得到的高品质高碳钢线材
CN110499452A (zh) 合金铸钢、其制作方法及应用
CN110438286A (zh) 一种控制焊丝钢连铸坯表面裂纹方法
CN114395727A (zh) 一种马氏体沉淀硬化不锈钢的冶炼及连铸工艺
CN112962025A (zh) 一种低成本保探伤低合金结构钢中厚板的生产方法
CN117840395B (zh) 低温钢的铸坯质量控制方法和板材生产方法
CN115058661A (zh) 一种高碳高锰钢板及其生产方法
CN116790841B (zh) 一种精确控制生态电炉冶炼18CrNiMo7-6齿轮钢铝氮比的生产工艺
CN111500919B (zh) 高洁净度高钛低碳钢的生产方法
CN109536835A (zh) 一种耐候耐低温热轧型钢及其制备方法
CN106048124A (zh) 铁水生产火车车轴钢的工艺及其台阶式吹氩密封结构
CN117230379A (zh) 一种生态电炉短流程制备窄淬透性20MnCr5H齿轮钢的冶炼工艺
CN108165892A (zh) 一种低温压力容器用35-50mm厚Q420R高强钢及其生产方法
CN115287522A (zh) 一种含硼钢连铸方坯裂纹的控制方法
CN115323257A (zh) 一种提高碳素结构钢q235方坯连铸生产效率的方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22897207

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 22897207

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 22897207

Country of ref document: EP

Kind code of ref document: A1