CN115522118B - Medium-carbon nitrogen-containing steel and slab continuous casting production method thereof - Google Patents
Medium-carbon nitrogen-containing steel and slab continuous casting production method thereof Download PDFInfo
- Publication number
- CN115522118B CN115522118B CN202110712314.4A CN202110712314A CN115522118B CN 115522118 B CN115522118 B CN 115522118B CN 202110712314 A CN202110712314 A CN 202110712314A CN 115522118 B CN115522118 B CN 115522118B
- Authority
- CN
- China
- Prior art keywords
- percent
- crystallizer
- continuous casting
- equal
- less
- 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.)
- Active
Links
Classifications
-
- 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
- B22D11/001—Continuous casting of metals, i.e. casting in indefinite lengths of specific alloys
-
- 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
- B22D11/181—Controlling or regulating processes or operations for pouring responsive to molten metal level or slag level
- B22D11/182—Controlling or regulating processes or operations for pouring responsive to molten metal level or slag level by measuring temperature
-
- 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
- B22D11/20—Controlling or regulating processes or operations for removing cast stock
-
- 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
- B22D11/22—Controlling or regulating processes or operations for cooling cast stock or mould
-
- 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
- B22D11/22—Controlling or regulating processes or operations for cooling cast stock or mould
- B22D11/225—Controlling or regulating processes or operations for cooling cast stock or mould for secondary cooling
-
- 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
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
-
- 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
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Continuous Casting (AREA)
Abstract
The invention discloses medium carbon nitrogen-containing steel and a slab continuous casting production method thereof, wherein the steel comprises the following elements in percentage by mass: c:0.15 to 0.60 percent, 0.7<Si≤2.0％，0.4<Mn is less than or equal to 4.0%, P is less than or equal to 0.04%, S is less than or equal to 0.04%, mn/S is less than or equal to 10 and less than or equal to 100%, al:0.1 to 0.2 percent, N:0.01 to 0.2 percent, one or more of Ti, B and Nb, 0.01 to 0.3 percent, more than or equal to 2 and less than or equal to 5 percent of Ti+B+Nb/N, and the balance of Fe and unavoidable impurities. After continuous annealing of the continuous casting slab through hot rolling and cold rolling, the HR30T hardness of the hardening and tempering degree T-5CA can reach 73-78; after the secondary cold rolling, the tensile strength in the rolling direction is about 75-85 kg/mm 2 。
Description
Technical Field
The invention relates to a manufacturing method for medium carbon nitrogen-containing steel and slab continuous casting without longitudinal cracks and transverse angle cracks, belonging to the technical field of metallurgy.
Background
The special material of the nitrogen-containing steel (the N mass fraction is more than 0.01%) is increasingly widely applied to the fields of energy, chemical industry, metallurgy, transportation, medical treatment and mechanical manufacturing due to the excellent mechanical property, corrosion resistance, oxidation resistance, wear resistance and the like. Due to the influence of the shortage of metallurgical resources-nickel, environmental protection materials and other factors, the nitrogen-containing steel is used as a new generation resource to save the steel and iron materials, and has received great attention from the international metallurgical world.
In the continuous casting process of the medium carbon nitrogen-containing steel, cracks can possibly occur from the crystallizer to the secondary cooling zone. When the continuous casting blank is in the crystallizer, element segregation among dendrites exists in the process of solidification of molten steel, on the other hand, because cooling at a vibration mark is weaker, generated austenite grains are coarse, the solidification thickness of the whole blank shell is uneven, cracks are easy to generate at the place where the blank shell is thin, and precipitation of oxysulfide of ferro-manganese at an austenite grain boundary weakens the grain boundary to initiate the cracks. After entering the secondary cooling zone, the thermal plasticity of the continuous casting blank can be greatly reduced due to the generation of precipitates such as AlN, mnS and the like in an austenite grain boundary in a high temperature zone and the generation of ferrite along with the generation of ferrite from austenite generated by the reduction of temperature. On the basis, if unreasonable conditions such as uneven cooling, uncomfortable strength and the like exist in secondary cooling, cracks can be generated and expanded in a large amount after continuous casting blanks are subjected to external stresses such as bending, straightening and thermal stress, and macroscopic corner transverse cracks are formed. As the temperature is further lowered, cementite formed at the grain boundaries also weakens the grain boundaries, enhancing crack sensitivity.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provide the medium carbon nitrogen-containing steel.
The technical problems to be solved by the method can be implemented by the following technical schemes.
The medium carbon nitrogen-containing steel comprises the following elements in percentage by weight:
c:0.15 to 0.60 percent, si is more than 0.7 and less than or equal to 2.0 percent, mn is more than 0.4 and less than or equal to 4.0 percent, P is less than or equal to 0.04 percent, S is less than or equal to 0.04 percent, mn/S is less than or equal to 10 and less than or equal to 100 percent, al:0.1 to 0.2 percent, N:0.01 to 0.2 percent; one or more of Ti, B and Nb, each of which is 0.01 to 0.3 percent, and 2.ltoreq.Ti+B+Nb/N.ltoreq.5 (the ratio range of the sum of Ti, B and Nb to N); the balance being Fe and unavoidable impurities.
As a preferred embodiment of the technical scheme, the steel grade of the substrate consists of the following elements in percentage by mass:
c: carbon is used as a solid solution strengthening element to improve the strength of the medium carbon nitrogen-containing steel tinplate; the carbon content is lower than 0.15%, and the strength does not meet the product requirement; the carbon content exceeds 0.6%, the brittleness of the product is enhanced, and the production difficulty is excessive. C of the invention: 0.15 to 0.60% (preferably 0.20 to 0.50%).
Si: silicon can increase solid solution strengthening performance, silicon content is lower than 0.7%, and solid solution strengthening effect is poor; however, if added in large amounts, the brittleness of the material is increased and the corrosion resistance is lowered, so that the silicon content is not preferably excessively high. The Si content of the invention is less than or equal to 2.0 percent (preferably, the Si content of 0.8 is less than or equal to 1.8 percent).
P and S: phosphorus and sulfur are harmful elements, can generate brittle materials with low melting point, and have high crack occurrence tendency, wherein the P is less than or equal to 0.04 percent, the S is less than or equal to 0.04 percent (preferably, the P is less than or equal to 0.02 percent, and the S is less than or equal to 0.02 percent).
Mn: manganese generally increases the toughness of steel, and increases the strength of steel through solid solution strengthening; in the solidification process, when the S content in the molten steel is high, thermal embrittlement is easy to occur, S and Fe are combined to generate FeS, surface cracks are easy to be caused by precipitation and aggregation at a grain boundary, and Mn has an inhibition effect on the occurrence of the phenomenon; because the affinity of Mn and S is greater than that of Fe and S, when Mn/S is increased to a certain degree, almost all S in molten steel is combined with Mn, formed MnS can replace low-melting-point FeS, the FeS is prevented from being precipitated at an austenite grain boundary, and meanwhile, the MnS is distributed in austenite in a linear form, so that the high-temperature thermoplastic property of steel can be improved, and the hot cracking tendency of a plate blank can be restrained. Meanwhile, in the solidification process of molten steel, mnS is preferentially precipitated in preference to AlN and BN, the AlN and the BN take the MnS precipitated earlier as heterogeneous core nucleation, and the precipitation of the AlN and the BN in a crystal boundary can be effectively reduced. Therefore, the Mn content range adopted by the invention is 1.0-4.0%. However, mn and S are combined to form MnS, so that the generation of transverse cracks at the angle of a casting blank is aggravated, and researches show that Mn/S is more than or equal to 100, so that the critical strain of the medium carbon steel can be improved, and the improvement of cracks is facilitated. The Mn is more than or equal to 0.4 and less than or equal to 4.0 percent, and the Mn/S is more than or equal to 10 and less than or equal to 100.
Al: al is used as a deoxidizer, and a proper amount of AlN can play a role in refining grains; a large amount of fine AlN in the steel is separated out along the grain boundary, the austenitic grain boundary strength is reduced, the steel is easy to crack along the grain boundary under the action of stress, and the plasticity of the tin-plated substrate is reduced, so that the Al content must be controlled within a reasonable range. Al of the present invention: 0.1 to 0.2% (preferably 0.11 to 0.18%).
N: the addition of N is beneficial to the subsequent continuous annealing, surface light rolling and other processing, and the higher the nitrogen content is, the better the processing and baking performance of the tin-plated substrate are; however, the increase of the [ N ] content in the steel can cause the transverse crack of the continuous casting billet angle and the enhancement of the sensitivity of gas precipitation, and the N of the invention comprehensively ensures the performance and the control quality: 0.01 to 0.2% (preferably 0.01 to 0.18%).
Ti, B, nb: n in the steel is fixed by adding Ti, B, nb and other elements into the molten steel to form TiN or BN or Nb (C, N) particles, so that the content of N combined with Al is reduced, alN precipitation is inhibited, and the transverse crack defect of the corner of a casting blank is reduced; excessive Ti, B and Nb are easy to generate excessive nitrides or carbonitrides, the material performance is reduced, and the content of one or more of Ti, B and Nb is 0.01-0.3%, and the content of Ti+B+Nb/N is more than or equal to 2 and less than or equal to 5.
The invention aims to provide a slab continuous casting production method of the medium carbon nitrogen-containing steel, so as to improve the quality of continuous casting slabs.
The technical scheme to be solved can be implemented by the following technical scheme.
In the continuous casting process, the section thickness of the slab x the width of the slab is (150-300) mm x (900-2150) mm, the superheat degree of a tundish is controlled at 10-40 ℃, and the average pulling speed is 1.0-2.5 m/min; the electromagnetic stirring current of the crystallizer is 500-600A, and the secondary cooling electromagnetic stirring current is 1000-2200A; the water quantity of the wide surface and the narrow surface of the crystallizer is 1400-3000L/min and 320-480L/min respectively, and the specific water quantity of the secondary cooling water is controlled to be 0.5+/-0.2L/kg; the vibration frequency of the crystallizer is 140-240 times/min (cpm), and the amplitude is 3-7 mm; the water gap insertion depth of the continuous casting crystallizer is controlled to be 120-180 mm; the taper of the narrow face of the crystallizer is 1.0-1.25%.
In the continuous casting process, aiming at the thickness of a section slab x the width of the slab (150-300) mm x (900-2150) mm, if the superheat degree of molten steel in the continuous casting process is lower than 10 ℃, the molten steel has poor fluidity, the molten steel at a water gap of a crystallizer is easily frozen, the casting is forced to be interrupted, and the casting powder melting effect is poor; if the superheat degree of the molten steel is higher than 40 ℃, segregation is very easy to occur, so that the solidification time is long, the selective crystallization is sufficient, and the quality problem of a casting blank is aggravated; the superheat degree of molten steel in the tundish is controlled to be 10-40 ℃.
In the continuous casting process, if the average pulling speed is higher than 2.5m/min, the primary blank shell is thinner, the casting blank is unevenly cooled, and longitudinal cracks and even steel leakage are easy to generate; considering the steelmaking continuous casting rhythm and the high drawing speed target, if the average drawing speed is not lower than 1.0m/min, the overall production capacity of the continuous casting machine is not affected; the average pulling speed of the invention is controlled to be 1.0-2.5 m/min.
In the continuous casting process, in order to prevent the medium carbon nitrogen-containing steel from generating cracks and depressions in the crystallizer, a weak cooling process system is preferably adopted in the crystallizer and the secondary cooling zone. The water quantity of the wide surface and the narrow surface of the crystallizer is 1400-3000L/min and 320-480L/min respectively. After entering the secondary cooling zone, the heat plasticity of the continuous casting blank can be greatly reduced due to the generation of precipitates such as AlN, mnS and the like in an austenite grain boundary in a high temperature zone and the generation of ferrite transformation from austenite to ferrite along with the reduction of temperature, and the specific water quantity of the secondary cooling water is controlled to be 0.5+/-0.2L/kg.
In the continuous casting process, the invention adds an electromagnetic stirring process in order to improve the segregation problem possibly caused in the continuous casting process. If the electromagnetic stirring current intensity of the crystallizer and the secondary cooling area is respectively lower than 500A and 1000A, the effect of improving the central quality of the casting blank is not achieved; if the electromagnetic stirring current intensity of the crystallizer and the secondary cooling area is higher than 600A and 2200A respectively, the fluctuation of the liquid level of the crystallizer is large, and the casting blank is easy to generate negative segregation; a large number of experiments show that the invention controls the electromagnetic stirring current of the crystallizer to be 500-600A and the secondary cooling electromagnetic stirring current to be 1000-2200A.
In the continuous casting process, high-frequency small-amplitude vibration is beneficial to reducing various surface defects of a casting blank, in particular to corner transverse cracks, slag inclusion and bubbles. The vibration frequency of the crystallizer is 140-240 times per minute (cpm), and the amplitude is 3-7 mm.
In the continuous casting process, if the insertion depth of the water gap of the crystallizer is too shallow, the impact of the water gap flow on a steel slag interface is strong, the reaction probability of molten steel and the protecting slag of the crystallizer is increased, and meanwhile, the meniscus slag-coiling probability is increased; if the water gap of the crystallizer is inserted too deeply, the casting blank is easy to crack; the water gap insertion depth of the continuous casting crystallizer designed by the invention is controlled to be 120-180 mm.
In the continuous casting process, an air gap is generated between a crystallizer and a casting blank in the solidification process, so that heat transfer is uneven, the growth thickness of the blank shell is uneven, surface pits or cracks are easy to form, and the reverse taper is arranged to compensate the shrinkage of the solidified blank shell. If the taper of the crystallizer is too small, the blank shell is easy to bulge; if the taper is too large, the friction force between the blank shell and the crystallizer copper plate is increased. The mold taper is generally selected based on the steel grade, the width of the strand and the draw rate. The narrow surface taper of the crystallizer designed by the invention is 1.0-1.25%.
As a preferable scheme, the superheat degree of molten steel in the tundish is controlled at 20-35 ℃ and the average pulling speed is controlled at 1.2-2.4 m/min.
Preferably, the electromagnetic stirring current of the crystallizer is 520-580A, and the secondary cooling electromagnetic stirring current is 1200-2000A.
As a preferable scheme, the water quantity of the wide surface and the narrow surface of the crystallizer is 1400-2800L/min and 350-450L/min respectively, and the specific water quantity of the secondary cooling water is controlled to be 0.5+/-0.1L/kg.
Preferably, the vibration frequency of the crystallizer is 150-220 times/min (cpm), and the amplitude is 4-6 mm.
Preferably, the insertion depth of the water gap of the continuous casting crystallizer is controlled to be 130-160 mm.
Preferably, the taper of the narrow surface of the crystallizer is 1.05-1.20%.
Compared with the prior art, the medium carbon nitrogen-containing steel and the slab continuous casting production method thereof have the characteristics of good surface and center quality of the continuous casting slab and the like, and are also beneficial to improving the quality of the continuous casting slab. After continuous annealing of the continuous casting slab through hot rolling and cold rolling, the HR30T hardness of the hardening and tempering degree T-5CA can reach 73-78; after the secondary cold rolling, the tensile strength in the rolling direction is about 75-85 kg/mm 2 。
The technology is a key technology for realizing continuous casting production and quality assurance of medium-carbon nitrogen-containing steel slabs. The method has popularization and application values for developing nitrogen-containing varieties and optimizing processes of enterprises adopting continuous casting process flows to realize production and test, improves productivity, reduces production cost and enhances comprehensive competitiveness of enterprises.
Detailed Description
The medium carbon nitrogen-containing steel and the slab casting process thereof according to the present invention will be further explained and illustrated with reference to specific examples, but the explanation and illustration do not unduly limit the technical scheme of the present invention.
The mass percentages of the chemical elements in the carbon-nitrogen-containing steels of examples 1 to 6 are shown in Table 1 below.
TABLE 1 (wt.%) Fe and other unavoidable impurities except P, S
The medium carbon nitrogen-containing steels of examples 1 to 6 of the present invention were prepared by the following continuous casting process:
in the continuous casting process, the superheat degree of a tundish is controlled at 10-40 ℃ and the average pulling speed is 1.0-2.5 m/min on a section with the thickness of a slab multiplied by the width of the slab (150-300) mm multiplied by (900-2150) mm; the electromagnetic stirring current of the crystallizer is 500-600A, and the secondary cooling electromagnetic stirring current is 1000-2200A; the water quantity of the wide surface and the narrow surface of the crystallizer is 1400-3000L/min and 320-480L/min respectively, and the specific water quantity of the secondary cooling water is controlled to be 0.5+/-0.2L/kg; the vibration frequency of the crystallizer is 140-240 cpm, and the amplitude is 3-7 mm; the water gap insertion depth of the continuous casting crystallizer is controlled to be 120-180 mm; the taper of the narrow face of the crystallizer is 1.0-1.25%.
Table 2 below sets forth specific process parameters of the manufacturing method of the medium carbon nitrogen-containing steel of examples 1 to 6.
Table 2:
the following table 3 lists the cast slab quality and product characteristics of the medium carbon nitrogen-containing steels of examples 1 to 6. The low-power performance test method of the continuous casting slab adopts a YB/T4003-2016 continuous casting slab low-power tissue defect rating chart.
Table 3:
| numbering device | HR30T hardness | Tensile Strength (kg/mm) 2 ) | Casting blank quality |
| Example 1 | 78 | 85 | No crack, class A center segregation 1.0 |
| Example 2 | 77 | 83 | No crack, class A center segregation 0.5 |
| Example 3 | 74 | 77 | No crack, class A center segregation 0.5 |
| Example 4 | 76 | 81 | No crack, class A center segregation 1.5 |
| Example 5 | 75 | 79 | No crack, class A center segregation 1.5 |
| Example 6 | 73 | 75 | No crack, class A center segregation 1.0 |
Finally, it should be noted that: the above embodiments are only for illustrating the present invention and not for limiting the technical solution described in the present invention; thus, while the invention has been described in detail with reference to the various embodiments described above, it will be understood by those skilled in the art that the invention may be modified or equivalents; all technical solutions and modifications thereof that do not depart from the spirit and scope of the present invention are intended to be included in the scope of the appended claims.
Claims (10)
1. The medium carbon nitrogen-containing steel is characterized by comprising the following elements or components in percentage by weight:
c:0.15 to 0.60 percent, si is more than 0.7 and less than or equal to 2.0 percent, mn is more than 0.4 and less than or equal to 4.0 percent, P is less than or equal to 0.04 percent, S is less than or equal to 0.04 percent, mn/S is less than or equal to 10 and less than or equal to 100 percent, al:0.1 to 0.2 percent, N:0.01 to 0.2 percent; one or more of Ti, B and Nb, wherein each content is 0.01-0.3%, and Ti+B+Nb/N is 2-5; the balance of Fe and unavoidable impurities; the slab of the medium carbon nitrogen-containing steel is prepared by adopting a continuous casting production method of the following continuous casting procedure:
the section thickness of the slab x the width of the slab is (150-300) mm x (900-2150) mm, the superheat degree of molten steel in the tundish is controlled at 10-40 ℃, and the average pulling speed is 1.0-2.5 m/min;
the electromagnetic stirring current of the crystallizer is 500-600A, and the secondary cooling electromagnetic stirring current is 1000-2200A;
the water quantity of the wide surface and the narrow surface of the crystallizer is 1400-3000L/min and 320-480L/min respectively, and the specific water quantity of the secondary cooling water is controlled to be 0.5+/-0.2L/kg;
the vibration frequency of the crystallizer is 140-240 times/min, and the amplitude is 3-7 mm; the water gap insertion depth of the continuous casting crystallizer is controlled to be 120-180 mm; the taper of the narrow face of the crystallizer is 1.0-1.25%.
2. The medium carbon nitrogen-containing steel according to claim 1, comprising the following elements or components in weight percent:
c:0.20 to 0.50 percent, 0.8< Si less than or equal to 1.8 percent, 0.4< Mn less than or equal to 4.0 percent, P less than or equal to 0.02 percent, S less than or equal to 0.02 percent, mn/S less than or equal to 10 and less than or equal to 100 percent, al:0.11 to 0.18 percent, N:0.01 to 0.18 percent; one or more of Ti, B and Nb, wherein each content is 0.01-0.3%, and Ti+B+Nb/N is 2-5; the balance being Fe and unavoidable impurities.
3. A slab continuous casting production method of medium carbon nitrogen-containing steel is characterized in that in the continuous casting process, the section thickness of a slab x the width of the slab is (150-300) mm x (900-2150) mm, the superheat degree of molten steel in a tundish is controlled at 10-40 ℃, and the average pulling speed is 1.0-2.5 m/min; the electromagnetic stirring current of the crystallizer is 500-600A, and the secondary cooling electromagnetic stirring current is 1000-2200A; the water quantity of the wide surface and the narrow surface of the crystallizer is 1400-3000L/min and 320-480L/min respectively, and the specific water quantity of the secondary cooling water is controlled to be 0.5+/-0.2L/kg; the vibration frequency of the crystallizer is 140-240 times/min, and the amplitude is 3-7 mm; the water gap insertion depth of the continuous casting crystallizer is controlled to be 120-180 mm; the taper of the narrow face of the crystallizer is 1.0-1.25%.
4. A slab continuous casting production method according to claim 3, wherein the superheat degree of molten steel in the tundish is controlled to be 20-35 ℃ and the average pulling speed is controlled to be 1.2-2.4 m/min.
5. A slab continuous casting production method according to claim 3, wherein the crystallizer electromagnetic stirring current is 520-580A, and the secondary cooling electromagnetic stirring current is 1200-2000A.
6. A slab continuous casting production method according to claim 3, wherein the water quantity of the wide surface and the narrow surface of the crystallizer is 1400-2800L/min and 350-450L/min respectively, and the specific water quantity of the secondary cooling water is controlled to be 0.5+/-0.1L/kg.
7. A slab continuous casting production method according to claim 3, wherein the vibration frequency of the crystallizer is 150-220 times/min, and the amplitude is 4-6 mm.
8. A slab continuous casting production method according to claim 3, wherein the insertion depth of the nozzle of the continuous casting crystallizer is controlled to be 130-160 mm.
9. A slab casting process according to claim 3 wherein the narrow face taper of the crystallizer is 1.05 to 1.20%.
10. A slab continuous casting production method according to claim 3, wherein the HR30T hardness of the temper degree T-5CA after the cast slab is continuously withdrawn by hot rolling and cold rolling is 73 to 78; after secondary cold rolling, the tensile strength in the rolling direction is 75-85 kg/mm 2 。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110712314.4A CN115522118B (en) | 2021-06-25 | 2021-06-25 | Medium-carbon nitrogen-containing steel and slab continuous casting production method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110712314.4A CN115522118B (en) | 2021-06-25 | 2021-06-25 | Medium-carbon nitrogen-containing steel and slab continuous casting production method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115522118A CN115522118A (en) | 2022-12-27 |
| CN115522118B true CN115522118B (en) | 2023-08-11 |
Family
ID=84693591
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110712314.4A Active CN115522118B (en) | 2021-06-25 | 2021-06-25 | Medium-carbon nitrogen-containing steel and slab continuous casting production method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115522118B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102051530A (en) * | 2011-01-12 | 2011-05-11 | 南京钢铁股份有限公司 | 48MnV nitrogenous steel and nitrogen adding process thereof |
| JP2014008513A (en) * | 2012-06-28 | 2014-01-20 | Jfe Steel Corp | Method for manufacturing continuously cast slab and method for manufacturing high strength cold-rolled steel sheet |
| JP2017066453A (en) * | 2015-09-29 | 2017-04-06 | Ｊｆｅスチール株式会社 | Cold rolled steel sheet, plating steel sheet and manufacturing method of them |
| CN108286023A (en) * | 2018-01-10 | 2018-07-17 | 唐山钢铁集团有限责任公司 | A kind of high manganese superhigh intensity cold rolling galvanized steel of middle carbon and its production method |
| CN110343954A (en) * | 2019-07-10 | 2019-10-18 | 宝钢特钢韶关有限公司 | A kind of connection rod of automobile engine steel and its manufacturing method |
| CN112442629A (en) * | 2019-08-28 | 2021-03-05 | 宝山钢铁股份有限公司 | Medium-carbon steel for mechanical structure and manufacturing method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105925887B (en) * | 2016-06-21 | 2018-01-30 | 宝山钢铁股份有限公司 | A kind of 980MPa levels hot-rolled ferrite-bainite dual-phase steel and its manufacture method |
-
2021
- 2021-06-25 CN CN202110712314.4A patent/CN115522118B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102051530A (en) * | 2011-01-12 | 2011-05-11 | 南京钢铁股份有限公司 | 48MnV nitrogenous steel and nitrogen adding process thereof |
| JP2014008513A (en) * | 2012-06-28 | 2014-01-20 | Jfe Steel Corp | Method for manufacturing continuously cast slab and method for manufacturing high strength cold-rolled steel sheet |
| JP2017066453A (en) * | 2015-09-29 | 2017-04-06 | Ｊｆｅスチール株式会社 | Cold rolled steel sheet, plating steel sheet and manufacturing method of them |
| CN108286023A (en) * | 2018-01-10 | 2018-07-17 | 唐山钢铁集团有限责任公司 | A kind of high manganese superhigh intensity cold rolling galvanized steel of middle carbon and its production method |
| CN110343954A (en) * | 2019-07-10 | 2019-10-18 | 宝钢特钢韶关有限公司 | A kind of connection rod of automobile engine steel and its manufacturing method |
| CN112442629A (en) * | 2019-08-28 | 2021-03-05 | 宝山钢铁股份有限公司 | Medium-carbon steel for mechanical structure and manufacturing method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115522118A (en) | 2022-12-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113637917B (en) | 690 MPa-grade ultrahigh-strength extra-thick ship plate steel with excellent low-temperature impact performance and production method thereof | |
| CN109666856A (en) | A kind of high-strength tenacity semiaxis non-hardened and tempered steel and its production method instead of 42CrMo quenched and tempered steel | |
| CN108866444B (en) | Corrosion-resistant mirror surface die steel and preparation method thereof | |
| CN110629114A (en) | Low-cost high-strength high-toughness bridge steel and preparation method thereof | |
| CN104928576A (en) | Production method of 260-330MPa low-alloy high-strength steel | |
| CN114892094B (en) | Pre-hardened mirror plastic die steel and production method thereof | |
| CN109930063B (en) | Steel for engineering machinery crawler chassis wheel body and production method thereof | |
| CN113604745A (en) | High-sulfur free-cutting tool steel bar and preparation method thereof | |
| WO2019029533A1 (en) | Cast steel, preparation method for cast steel and use of cast steel | |
| CN106521332B (en) | A kind of resistance to stress guiding hydrogen induced cracking (HIC) steel plate and its production method | |
| CN113061815A (en) | 800 MPa-grade quenched and tempered high-strength steel with stable full-section impact performance and production method thereof | |
| CN112143970A (en) | High-strength high-toughness non-quenched and tempered front axle steel and production method thereof | |
| CN115522118B (en) | Medium-carbon nitrogen-containing steel and slab continuous casting production method thereof | |
| CN114807773A (en) | High-mechanical-property steel for wind driven generator shaft and preparation process thereof | |
| CN112143980A (en) | Steel 27SiMn2 for industrial forks and preparation method thereof | |
| CN116121629B (en) | Preparation method of gear steel 18CrNiMo7-6 | |
| CN115125434B (en) | Low-carbon high-nitrogen tinned substrate and slab continuous casting production method thereof | |
| CN116288000B (en) | Impact-welded axle housing steel plate with excellent ductility and welding performance and tensile strength of 630MPa and preparation method thereof | |
| CN115141985B (en) | Medium-carbon high-titanium boron-containing steel with high hardenability and slab continuous casting production method thereof | |
| CN115537663B (en) | High-silicon high-nitrogen non-quenched and tempered steel and preparation method thereof | |
| CN113549831B (en) | 1500MPa heat-treatment-free low-cost troostite cutting tool steel and production method thereof | |
| CN115094305B (en) | High-temperature carburized gear steel and manufacturing method thereof | |
| CN115044827B (en) | Production method of low-carbon gear steel free of isothermal annealing | |
| CN114774772B (en) | Corrosion-resistant 500HB martensite wear-resistant steel plate and production method thereof | |
| CN117210770B (en) | Steel plate for high-strength homogenized ferrite ultra-thick wind power structure and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |