CN113652609A - Low-cost 42CrMoA round steel and production method thereof - Google Patents
Low-cost 42CrMoA round steel and production method thereof Download PDFInfo
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Abstract
The invention belongs to the technical field of round steel, and particularly relates to low-cost 42CrMoA round steel and a production method thereof; the steel comprises the following components: c: 0.41 to 0.43%, Mn: 0.63-0.66%, Si: 0.20 to 0.35%, Mo: 0.16-0.17%, Cr: 0.98-0.99%, Ni: less than or equal to 0.30 percent, P: less than or equal to 0.020%, S: less than or equal to 0.020%, Cu: less than or equal to 0.20 percent, Alt: 0.010-0.030%, and the balance of Fe and inevitable impurities; the method comprises the steps of converter smelting, LF refining, continuous casting, casting blank wind shielding and stack cooling, heating, rolling, high-temperature shearing and hot steel collection; according to the invention, by optimizing the components and the process, the cost of each ton of steel is reduced, and the strength and the toughness of the steel are improved; the 42CrMoA round steel with the performance and flaw detection protection is obtained, and the application prospect is good.
Description
Technical Field
The invention belongs to the technical field of small round steel bars in continuous casting production, and particularly relates to low-cost 42CrMoA round steel and a production method thereof.
Background
The 42CrMoA is common high-hardenability alloy structural steel, has higher strength and good toughness, good cold strain plasticity and no obvious temper brittleness. After quenching and tempering or carburizing treatment, the alloy has higher fatigue limit and impact resistance, has good comprehensive mechanical property, and is widely applied to processing high-pressure pipelines and mechanical parts such as fasteners, gears, shafts and the like; but the production cost of the 42CrMoA round steel is always in a higher level at present; with the increasing market competition, the cost of steel per ton is reduced at the forefront.
In the production process of round steel at present, the continuous casting billet has center segregation and the cooling process in the rolling process is improper, so that the end part of the steel product generates center cracks, and the mechanical property of the round steel cannot be ensured; meanwhile, in order to reduce the cost of steel per ton, the use of certain noble metal elements is reduced blindly, and the performance of the steel is damaged while the cost is reduced.
Disclosure of Invention
The invention aims to overcome the technical defects in the prior art, and reduce the cost of steel per ton while ensuring the mechanical property of round steel.
In order to achieve the purpose, the invention firstly provides a low-cost 42CrMoA round steel which comprises the following components in percentage by weight:
c: 0.38-0.44%, Mn: 0.50-0.80%, Si: 0.17 to 0.35%, Mo: 0.15 to 0.25%, Cr: 0.90-1.20%, Ni: less than or equal to 0.30 percent, P: less than or equal to 0.020%, S: less than or equal to 0.020%, Cu: less than or equal to 0.20 percent, Alt: 0.010-0.030%, and the balance of Fe and inevitable impurities.
Designing chemical components:
in order to meet the requirement of structure design, the production process and the technical level of smelting are considered, and the chemical components of the 42CrMoA steel are designed from the perspective of saving cost on the premise of meeting the chemical components, the mechanical properties and the macrostructure specified by the standard (as shown in Table 1).
Table 1 ingredient design:
the specific components are optimally designed as follows: c: 0.41 to 0.43%, Mn: 0.63-0.66%, Si: 0.20 to 0.25%, Mo: 0.16-0.17%, Cr: 0.98-0.99%, Ni: less than or equal to 0.30 percent, P: less than or equal to 0.020%, S: less than or equal to 0.020%, Cu: less than or equal to 0.20 percent, Alt: 0.010-0.030%, and the balance of Fe and inevitable impurities.
The chemical components of the 42CrMoA combined round steel developed for research and development are compared with those of the traditional component alloy structural steel; as can be seen from the table, the ranges of the components of Si and Mn are reduced, and the addition of Al can play a role in refining and strengthening crystal grains, thereby being beneficial to the stability of product performance and the processing of the product.
Mn is a solid solution strengthening element and is beneficial to improving the strength and the toughness of the round steel; cr and iron form a continuous solid solution, an austenite phase region is reduced, the strength and the hardenability are obviously improved, the strength of the round steel is improved, and the round steel has good wear resistance; mo is dissolved in steel in a solid state and has the functions of eliminating temper brittleness, refining grains and improving the hardenability of the steel. On the basis of ensuring that the mechanical property is qualified, in order to save cost, the lower limit of the Mo content in 42CrMoA is controlled to be 0.16-0.17%.
In order to achieve various properties of finished products and ensure that the strength and the plasticity of the steel are well matched, the chemical components of steel are strictly controlled, the content of Mn needs to be properly increased, the content of Si needs to be reduced, the content of Mo needs to be properly reduced, partial Mn and Cr need to replace partial Mo alloy elements, and the cost of per ton steel is reduced; the method seems to be simple adjustment, and is a result which can be obtained through a large amount of creative experiments, the dosage of the method needs to be strictly controlled, the method is not realized by simple adjustment, and otherwise, the performance of steel is influenced; the tempering stability can be ensured under the limited condition of the invention; meanwhile, the content of Al is controlled, so that the content is not too large, otherwise, side effects are caused; the dosage is controlled to be 0.010-0.030 percent, Al in the steel is mainly used for fixing free N in the steel and reducing work hardening in the cold machining process, and on the other hand, the Al also plays a role in refining grains.
The invention also provides a production method of the low-cost 42CrMoA round steel, which comprises the following steps:
the method comprises the steps of converter smelting, LF refining, continuous casting, wind shielding and pile cooling of a casting blank, heating, rolling, high-temperature shearing and hot steel collection.
(1) In the converter smelting: the carbon content of the converter tapping is 0.12-0.20%, and the phosphorus content P of the converter tapping is less than or equal to 0.015%; the end point temperature is more than or equal to 1600 ℃;
(2) LF refining, in which Al-Si is used as a main diffusion deoxidation component to improve the purity of molten steel, and Al refines the grain size of steel; the station-entering temperature is more than or equal to 1512 ℃, the station-exiting temperature is 1542-1557 ℃, and the white slag retention time is more than or equal to 15 min;
(3) continuous casting: the superheat degree of the molten steel in the tundish is 20-40 ℃; controlling the drawing speed of the continuous casting blank to be 1.0-1.1 m/min; electromagnetic stirring is adopted by a crystallizer in the continuous casting process;
(4) and (3) cooling in a heaped mode: wind-shielding and pile-cooling the continuous casting billet obtained after continuous casting for not less than 36 h;
(5) heating: heating and insulating the continuously cast bloom after the stack cooling treatment at 1150-1250 ℃, wherein the insulating time is not less than 3 hours; rolling the mixture into round steel after heat preservation;
(6) descaling and rolling: descaling round steel, wherein 1050-1220 ℃ is adopted in a rough rolling stage, 900-1050 ℃ is adopted in a finish rolling stage, and 800-900 ℃ is adopted in a cooling bed;
(7) shearing at high temperature after rolling, wherein the shearing temperature is more than or equal to 450 ℃, and obtaining sheared round steel;
(8) and (4) collecting hot steel.
Further, the end point temperature in the step (1) is 1607-1639 ℃.
Further, the arrival temperature in the step (2) is 1512-1520 ℃; the white slag holding time is 15-16 min.
Furthermore, in the step (3), the electromagnetic stirring adopts a process of first stirring I-400A, f-2 Hz, last stirring I-400A, and f-10 Hz, so that the columnar crystals can be broken, the equiaxial crystals can be increased, the growth of the columnar crystals can be effectively controlled, and the equiaxial crystal rate can be increased.
Further, the heap cooling time in the step (4) is 36-37 h.
Further, in the step (6), the dephosphorization pressure is 18-21 MPa.
Further, in the step (7), the shearing temperature is 450-460 ℃.
Further, in the step (8), the hot steel collection operation comprises the following specific steps: the stacking temperature of the cut round steel is more than or equal to 200 ℃, and the wind shielding and slow cooling are not less than 36 h; the central porosity of the round steel is not more than 1.0 grade, and the shrinkage cavity is not more than 0.5 grade.
The invention has the advantages and technical effects that:
the 42CrMoA round steel with excellent strength, toughness and processability is obtained; mn is a solid solution strengthening element and is beneficial to improving the strength and the toughness of the round steel; cr and iron form a continuous solid solution, an austenite phase region is reduced, the strength and the hardenability are obviously improved, the strength of the round steel is improved, and the round steel has good wear resistance; mo is dissolved in steel in a solid state and has the functions of eliminating temper brittleness, refining grains and improving the hardenability of the steel. On the basis of ensuring that the mechanical property is qualified, in order to save cost, the lower limit of the Mo content in 42CrMoA is controlled to be 0.16-0.17%; the invention has the advantages that the ranges of Si and Mn components are reduced, and Al is added to play a role in refining crystal grains, thereby being beneficial to the stable performance of products and the processing of the products; the cost of each ton of steel is reduced, and meanwhile, the strength and the toughness of the steel are improved.
The production process of the invention adopts a non-VD procedure for steel making in combination with the improvement of the process steps, thereby further saving the cost while not influencing the performance of steel.
The crystallizer in the continuous casting process adopts electromagnetic stirring; the electromagnetic stirring adopts the process of firstly stirring I (400A), f (2 Hz), secondly stirring I (400A) and finally stirring F (10 Hz), so that the columnar crystals can be broken, the isometric crystals can be increased, the growth of the columnar crystals can be effectively controlled, and the isometric crystal rate can be increased.
Through the simple and effective process flow design, the phenomenon that the end part of a steel product generates central cracks due to the fact that the continuous casting billet has central segregation and the cooling process is improper in the rolling process is avoided; the indexes of mechanical property, ultrasonic flaw detection and the like of the round steel are ensured; the cost is saved by 70-80 yuan/ton, the cost of steel per ton is greatly reduced, the 42CrMoA round steel with the specification of 20-50 mm and the performance and flaw detection guarantee is obtained at low cost, and the method has good popularization significance.
Detailed Description
The present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.
Comparative example 1:
this 42CrMoA round steel product diameter 50mm, traditional chemical composition: c: 0.42%, Si: 0.26%, Mn: 0.65%, Cr: 0.97%, Mo: 0.18%, P: 0.015%, S: 0.014%, Ni: 0.02%, Cu: 0.02%, the balance being Fe and unavoidable impurities;
the process comprises the following steps: the method comprises the steps of converter smelting, LF refining, VD vacuum, continuous casting, wind shielding and stack cooling of a casting blank, heating, rolling, high-temperature shearing and collection.
(1) In the converter smelting: the carbon content of the steel tapping is 0.12 percent, and the phosphorus content of the steel tapping is 0.014 percent; end temperature 1605 ℃;
(2) LF refining: adding lime and fluorite to adjust the fluidity of the slag, keeping the white slag for 15min, and keeping the leaving temperature at 1630 ℃.
(3) VD vacuum: high vacuum degree 67Pa, and holding time 15 min.
(4) Continuous casting: the superheat degree of the molten steel in the tundish is 40 ℃; controlling the drawing speed of the continuous casting blank to be 1.0 m/min;
(5) wind shielding and pile cooling are carried out on the continuous casting billet for 36 hours;
(6) heating: heating and preserving heat for 3 hours at 1150 ℃ for the continuous casting billet to be rolled into round steel;
(7) descaling and rolling: descaling the round steel, wherein the dephosphorization pressure is 21 MPa; the rough rolling stage is 1150 ℃, the finish rolling stage is 1050 ℃, and the temperature of the steel plate entering a cooling bed is 850 ℃;
(8) shearing at high temperature after rolling, wherein the shearing temperature is 400 ℃;
(9) collecting hot steel, stacking round steel among other hot steel, and keeping away from wind and slowly cooling for 36 h; the center of the hot-rolled round steel is loose by 1.0 grade, and the shrinkage cavity is contracted by 0.5 grade; the diameter of the round steel product is 50 mm.
Example 1:
the diameter of the 42CrMoA round steel product is 45mm, and the chemical components and the mass percentage are shown in Table 3.
The method comprises the following steps: the method comprises the steps of converter smelting, LF refining, continuous casting, wind shielding and pile cooling of a casting blank, heating, rolling, high-temperature shearing and hot steel collection.
(1) In the converter smelting: the carbon content of the tapped steel is 0.12 percent, and the phosphorus content of the tapped steel is 0.015 percent; end temperature 1607 ℃;
(2) LF refining, wherein the station entering temperature is 1512 ℃, the station exiting temperature is 1542 ℃, and the white slag retention time is 16 min.
(3) Continuous casting: the superheat degree of the molten steel in the tundish is 40 ℃; controlling the drawing speed of the continuous casting blank to be 1.0 m/min;
(4) and (3) cooling in a heaped mode: wind shielding and pile cooling are carried out on the continuous casting billet for 36 hours;
(5) heating: heating and preserving heat for 3 hours at 1160 ℃ for the continuous casting billet, and rolling the continuous casting billet into round steel;
(6) descaling and rolling: descaling the round steel, wherein the dephosphorization pressure is 24 MPa; the rough rolling stage is 1150 ℃, the finish rolling stage is 1050 ℃, and the temperature of the steel plate entering a cooling bed is 850 ℃;
(7) shearing at high temperature after rolling, wherein the shearing temperature is 450 ℃;
(8) and (4) collecting hot steel, stacking round steel among other hot steel, and keeping out wind for slow cooling for 37 h. The center of the hot-rolled round steel is loose by 1.0 grade, and the shrinkage cavity is contracted by 0.5 grade.
Example 2:
the diameter of the 42CrMoA round steel product is 40mm, and the chemical components and the mass percentage are shown in Table 3.
The method comprises the following steps: the method comprises the steps of converter smelting, LF refining, continuous casting, wind shielding and pile cooling of a casting blank, heating, rolling, high-temperature shearing and hot steel collection.
(1) In the converter smelting: the carbon content of the steel tapping is 0.13 percent, and the phosphorus content of the steel tapping is 0.007 percent; end point temperature 1639 ℃;
(2) LF refining: the station entrance temperature is 1520 ℃, the station exit temperature is 1545 ℃, and the white slag holding time is 15 min;
(3) continuous casting: the superheat degree of the molten steel in the tundish is 40 ℃; controlling the drawing speed of the continuous casting blank to be 1.0 m/min;
(4) and (3) cooling in a heaped mode: wind shielding and pile cooling are carried out on the continuous casting billet for 37 hours;
(5) heating: heating the continuous casting billet at 1170 ℃, preserving heat for 3 hours and rolling the continuous casting billet into round steel;
(6) descaling and rolling: descaling the round steel, wherein the dephosphorization pressure is 21 MPa; the rough rolling stage is 1100 ℃, the finish rolling stage is 950 ℃, and the temperature of the steel plate entering a cooling bed is 900 ℃;
(7) shearing at high temperature of 460 ℃ after rolling;
(8) and (4) collecting hot steel, stacking round steel among other hot steel, and keeping away wind for slow cooling for 36.5 h. The center of the hot-rolled round steel is loose by 1.0 grade, and the shrinkage cavity is contracted by 0.5 grade.
Example 3:
the diameter of the 42CrMoA round steel product is 50mm, and the chemical components and the mass percentage are shown in Table 3.
The method comprises the following steps: the method comprises the steps of converter smelting, LF refining, continuous casting, wind shielding and pile cooling of a casting blank, heating, rolling, high-temperature shearing and hot steel collection.
(1) In the converter smelting: the carbon content of the steel tapping is 0.12 percent, and the phosphorus content of the steel tapping is 0.010 percent; the end point temperature is 1610 ℃;
(2) LF refining, wherein the station entry temperature is 1518 ℃, the station exit temperature is 1550 ℃, and the white slag retention time is 15 min;
(3) continuous casting: the superheat degree of the molten steel in the tundish is 35 ℃; controlling the drawing speed of the continuous casting blank to be 1.1 m/min;
(4) and (3) cooling in a heaped mode: wind shielding and pile cooling are carried out on the continuous casting billet for 36 hours;
(5) heating: heating and preserving heat of the continuous casting billet at 1180 ℃ for 3 hours, and rolling the continuous casting billet into round steel;
(6) descaling and rolling: descaling the round steel, wherein the dephosphorization pressure is 21 MPa; the rough rolling stage is 1190 ℃, the finish rolling stage is 960 ℃, and the temperature of the steel plate entering a cooling bed is 810 ℃;
(7) shearing at high temperature after rolling, wherein the shearing temperature is 450 ℃;
(8) and (4) collecting hot steel, stacking round steel among other hot steel, and keeping out wind for slow cooling for 37.5 h. The center of the hot-rolled round steel is loose by 1.0 grade, and the shrinkage cavity is contracted by 0.5 grade.
And (3) displaying effect data:
(1) cost-effectiveness:
calculated at the current market price: the Mn is increased by 0.01 percent, and the cost of each ton of steel is about 1.0 yuan; 0.01 percent of Cr is added, and the cost of each ton of steel is about 1.5 yuan; 0.01 percent of Mo is added, and the cost of each ton of steel is about 22 yuan.
1) Comparative example 1: the component (A) contains Mn: 0.64%, Cr: 0.97%, Mo: 0.18 percent;
example 1: the component (A) contains Mn: 0.65%, Cr: 0.99%, Mo: 0.17 percent;
example 2: the component (A) contains Mn: 0.66%, Cr: 0.99%, Mo: 0.16 percent;
example 3: the component (A) contains Mn: 0.66%, Cr: 0.99%, Mo: 0.16 percent;
in the embodiment, part of Mn and Cr are used for replacing part of Mo alloy elements, the cost of Mn per ton of steel is increased by 1.0-2.0 yuan, the cost of Cr per ton of steel is increased by 3.0 yuan, the cost of Mo per ton of steel is reduced by 22 yuan, and the total composition of Mn and Cr is not more than 5.0 yuan; the pure photosynthetic gold reduces the cost by about 17 yuan.
2) The VD procedure is simplified and cancelled in the process steps, and the cost is saved by 60 yuan/ton;
through component and process optimization, the cost is saved by 70-80 yuan/ton, and the method has good popularization significance.
(2) Chemical components:
TABLE 2 melting composition
(3) Performance indexes are as follows:
TABLE 342 CrMoA round steel product mechanical property test results
The results show that the 42CrMoA round steel with excellent strength, toughness and processability is obtained; mn is a solid solution strengthening element and is beneficial to improving the strength and the toughness of the round steel; cr and iron form a continuous solid solution, an austenite phase region is reduced, the strength and the hardenability are obviously improved, the strength of the round steel is improved, and the round steel has good wear resistance; mo is dissolved in steel in a solid state and has the functions of eliminating temper brittleness, refining grains and improving the hardenability of the steel. On the basis of ensuring that the mechanical property is qualified, in order to save cost, the lower limit of the Mo content in 42CrMoA is controlled to be 0.16-0.17%; the invention has the advantages that the ranges of Si and Mn components are reduced, and Al is added to play a role in refining crystal grains, thereby being beneficial to the stable performance of products and the processing of the products; the cost of each ton of steel is reduced, and meanwhile, the strength and the toughness of the steel are improved.
The production process of the invention adopts a non-VD procedure for steel making in combination with the improvement of the process steps, thereby further saving the cost while not influencing the performance of steel.
Description of the drawings: the above embodiments are only used to illustrate the present invention and do not limit the technical solutions described in the present invention; thus, while the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted; all such modifications and variations are intended to be included herein within the scope of this disclosure and the present invention and protected by the following claims.
Claims (10)
1. A low-cost 42CrMoA round steel is characterized by comprising the following components in percentage by weight:
c: 0.38-0.44%, Si: 0.17-0.35%, Mn: 0.50-0.80%, P is less than or equal to 0.020%, S is less than or equal to 0.020%, Cr: 0.90-1.20%, Ni is less than or equal to 0.30%, Mo: 0.15-0.25%, less than or equal to 0.030% of Al, less than or equal to 0.2% of Cu, and the balance of Fe and inevitable impurities.
2. The low-cost 42CrMoA round steel as claimed in claim 1, which is prepared from the following components in percentage by weight: c: 0.41-0.43, Mn%: 0.63-0.66%, Si: 0.20 to 0.25%, Mo: 0.16-0.17%, Cr: 0.98-0.99%, Ni: less than or equal to 0.30 percent, P: less than or equal to 0.020%, S: less than or equal to 0.020%, Cu: less than or equal to 0.20 percent, Alt: 0.010-0.030%, and the balance of Fe and inevitable impurities; the diameter of the round steel is 20-50 mm.
3. The production process of the low-cost 42CrMoA round steel according to claim 1 or 2, characterized by comprising the following steps:
(1) in the converter smelting: the carbon content of the converter tapping is 0.12-0.20%, and the phosphorus content P of the converter tapping is less than or equal to 0.015%; the end point temperature is more than or equal to 1600 ℃;
(2) LF refining, namely performing diffusion deoxidation by taking Al-Si as a main component, improving the purity of molten steel, and refining the grain size of steel by Al; the station-entering temperature is more than or equal to 1512 ℃, the station-exiting temperature is 1542-1557 ℃, and the white slag retention time is more than or equal to 15 min;
(3) continuous casting: the superheat degree of the molten steel in the tundish is 20-40 ℃; controlling the drawing speed of the continuous casting blank to be 1.0-1.1 m/min; electromagnetic stirring is adopted by a crystallizer in the continuous casting process;
(4) and (3) cooling in a heaped mode: wind-shielding and pile-cooling the continuous casting billet obtained after continuous casting for not less than 36 h;
(5) heating: heating and insulating the continuously cast bloom after the stack cooling treatment at 1150-1250 ℃, wherein the insulating time is not less than 3 hours; rolling the mixture into round steel after heat preservation;
(6) descaling and rolling: descaling round steel, wherein 1050-1220 ℃ is adopted in a rough rolling stage, 900-1050 ℃ is adopted in a finish rolling stage, and 800-900 ℃ is adopted in a cooling bed;
(7) shearing at high temperature after rolling, wherein the shearing temperature is more than or equal to 450 ℃, and obtaining sheared round steel;
(8) and (4) collecting hot steel.
4. The production process of the low-cost 42CrMoA round steel as claimed in claim 3, wherein the end point temperature in step (1) is 1607-1639 ℃.
5. The production process of the low-cost 42CrMoA round steel according to claim 3, characterized in that the arrival temperature in the step (2) is 1512-1520 ℃; the white slag holding time is 15-16 min.
6. The process for producing 42CrMoA round steel with low cost according to claim 3, wherein the electromagnetic stirring in the step (3) adopts a process of firstly stirring I-400A, then stirring f-2 Hz, and secondly stirring I-400A, then stirring f-10 Hz.
7. The production process of the low-cost 42CrMoA round steel as claimed in claim 3, wherein the heap cooling time in the step (4) is 36-37 h.
8. The production process of the low-cost 42CrMoA round steel as claimed in claim 3, wherein in the step (6), the dephosphorization pressure is 18-21 MPa.
9. The production process of the low-cost 42CrMoA round steel as claimed in claim 3, wherein in the step (7), the shearing temperature is 450-460 ℃.
10. The production process of low-cost 42CrMoA round steel according to claim 3, characterized by comprising the following specific operations of hot steel collection in step (8): the stacking temperature of the cut round steel is more than or equal to 200 ℃, and the wind shielding and slow cooling are not less than 36 h; the central porosity of the round steel is not more than 1.0 grade, and the shrinkage cavity is not more than 0.5 grade.
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Cited By (4)
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| CN114717393A (en) * | 2022-04-22 | 2022-07-08 | 江苏永钢集团有限公司 | Rapid isothermal spheroidizing annealing method for 42CrMoA steel bar |
| CN115044823A (en) * | 2022-06-28 | 2022-09-13 | 江苏永钢集团有限公司 | Production process of ultra-supercritical high-pressure boiler steel P92 continuous casting round billet |
| CN115612938A (en) * | 2022-11-15 | 2023-01-17 | 江苏永钢集团有限公司 | High-low temperature resistant alloy structural steel for petroleum pipeline and production method thereof |
| CN116288002A (en) * | 2023-03-08 | 2023-06-23 | 武汉钢铁有限公司 | Medium-high carbon alloy structural steel for fine blanking and manufacturing method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114717393A (en) * | 2022-04-22 | 2022-07-08 | 江苏永钢集团有限公司 | Rapid isothermal spheroidizing annealing method for 42CrMoA steel bar |
| CN115044823A (en) * | 2022-06-28 | 2022-09-13 | 江苏永钢集团有限公司 | Production process of ultra-supercritical high-pressure boiler steel P92 continuous casting round billet |
| CN115612938A (en) * | 2022-11-15 | 2023-01-17 | 江苏永钢集团有限公司 | High-low temperature resistant alloy structural steel for petroleum pipeline and production method thereof |
| CN116288002A (en) * | 2023-03-08 | 2023-06-23 | 武汉钢铁有限公司 | Medium-high carbon alloy structural steel for fine blanking and manufacturing method thereof |
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