CN110923549A - 900 MPa-grade hot-rolled high-strength structural steel for crane boom and production method thereof - Google Patents
900 MPa-grade hot-rolled high-strength structural steel for crane boom and production method thereof Download PDFInfo
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- 229910000746 Structural steel Inorganic materials 0.000 title claims abstract description 23
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 19
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 41
- 239000010959 steel Substances 0.000 claims abstract description 41
- 239000000126 substance Substances 0.000 claims abstract description 4
- 238000001816 cooling Methods 0.000 claims description 20
- 238000005096 rolling process Methods 0.000 claims description 15
- 238000005266 casting Methods 0.000 claims description 10
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 10
- 229910045601 alloy Inorganic materials 0.000 claims description 9
- 239000000956 alloy Substances 0.000 claims description 9
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0203—Cooling
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/002—Heat treatment of ferrous alloys containing Cr
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/005—Heat treatment of ferrous alloys containing Mn
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/008—Heat treatment of ferrous alloys containing Si
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0081—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for slabs; for billets
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/002—Bainite
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/008—Martensite
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Abstract
The invention provides a 900 MPa-level hot-rolled high-strength structural steel for a crane boom and a production method thereof, wherein the structural steel comprises the following chemical components in percentage by weight: the invention adopts low-carbon alloy components, steel making and a proper TMCP process to produce the steel with 900 MPa-level tensile strength, the yield strength of the steel reaches more than 800MPa, the tensile strength of the steel is more than 900MPa, the elongation of the steel is more than or equal to 21 percent, the Charpy impact toughness impact energy at minus 20 ℃ is more than 84J, the cold bending d at 180 degrees is qualified as 2a, and the welding performance is good.
Description
Technical Field
The invention belongs to the technical field of structural steel production, and particularly relates to 900 MPa-level hot-rolled high-strength structural steel for a crane boom and a production method thereof.
Background
The steel used at important parts such as crane booms and the like is required to have high strength and also required to have good plastic toughness and welding performance so as to ensure the safety performance, the steel is used as a hoisting device which is different from the working environment of other engineering vehicles and mainly bears the hoisting work of high-weight goods, and the steel needs to have high strength to ensure the safety in the case of severe working environment, but the steel is low in strength of the steel for crane booms developed at home at present, so that the development of the steel for the high-strength crane booms is necessary.
Disclosure of Invention
In order to solve the technical problems, the invention provides 900 MPa-grade hot-rolled high-strength structural steel for a crane boom and a production method thereof. The hot-rolled structural steel with 900 MPa-level tensile strength, good plastic toughness and good welding performance is produced by adopting low-carbon alloy components, steel making and a proper TMCP (thermal mechanical control processing) process.
The technical scheme adopted by the invention is as follows:
the structural steel for the 900 MPa-level hot-rolled high-strength crane boom comprises the following chemical components in percentage by weight: 0.050 to 0.070C, 0.10 to 0.20 Si, 1.70 to 1.90 Mn, less than or equal to 0.020P, less than or equal to 0.010S, 0.020 to 0.060 Als0.06 to 0.08 Nb0.08 Mo0.08 to 0.12 Ti, 0.11 to 0.13 Cr, and the balance of Fe and inevitable impurities.
Furthermore, the metallographic structure of the structural steel for the 900 MPa-grade hot-rolled high-strength crane boom is acicular ferrite, granular bainite and tempered martensite, wherein the percentage of the granular bainite and the tempered martensite is 45% -40% and 15% -10%, respectively, and the grain size grade of the structural steel is 8 grade.
The invention also provides a production method of the 900 MPa-level hot-rolled high-strength structural steel for the crane boom, which comprises the following steps: molten iron pretreatment → converter smelting → alloy fine tuning station → LF refining → continuous casting → casting blank heat treatment → controlled rolling and controlled cooling → leveling → transverse cutting → finished product; wherein, the casting blank requires stacking and slow cooling treatment, the red blank is stacked in time, and the slow cooling time is 96 hours.
Further, the molten iron is subjected to desulfurization pretreatment to reduce the S content, and slag skimming is performed before and after; the converter production department needs to strengthen the slag stopping work of tapping, deoxidation alloying is carried out in the slag discharging process, and an alloy fine adjustment station adds aluminum particles and strongly stirs to preliminarily reduce top slag.
FeTi70 is used at the LF furnace, and the total weak stirring time before and after the calcium feeding is ensured to be more than 15 min; the target temperature of the ladle in the continuous casting zone is controlled to be 30 ℃ above the liquidus temperature.
The casting blank is cold-charged into a furnace, and the in-furnace time is 4 hours; the tapping temperature of the steel billet is controlled according to 1300 ℃, the steel grade is required to reach the complete austenitizing temperature when the casting blank is heated in the furnace, but the steel grade can not be softened and energy loss can not be caused by too high heating, and the 1300 ℃ is most suitable in consideration of the heat loss of subsequent rough rolling, finish rolling and cooling sections.
In the controlled rolling and controlled cooling step, the pressing mode of the roughing mill is a 3+5 mode, and all seven frames of the finishing mill are put into use.
The reduction rate of the finishing mill group adopts a balanced distribution mode, the reduction of F4-F7 frames is increased to 35-25%, and the finish rolling compression ratio is controlled according to 4.0.
The cooling after rolling adopts a full-section laminar cooling mode, the cooling speed is controlled to be 40-45 ℃/s, the lowest cooling speed is controlled to be 40 ℃/s, the generation of granular bainite and tempered martensite can be increased by properly increasing the cooling speed, the strength of the plate blank is increased to a certain extent, the excessive transformation of ferrite is avoided, and the plasticity and toughness of the plate blank cannot be influenced. If the cooling speed is too fast, the strength is too high, the ductility and toughness are too low, the mechanical property is influenced, and the coiling is difficult in the subsequent slab coiling process.
The soaking temperature is 1300-1400 ℃, the finish rolling temperature is 850-900 ℃, and the coiling position temperature is 500-550 ℃.
According to the technical scheme provided by the invention, in the alloy components for reducing C and controlling low Si, the structural characteristics of steel grades are changed by adding a proper amount of alloy elements, and through multiple test summaries, steel grades with Nb, Mo, Ti and Cr elements added in the steel grades are developed, wherein the Mo element can keep the hardness of steel, increase the resistance to deformation, cracking and abrasion, eliminate residual stress to a certain extent and increase the ductility and toughness. Ti element raises the strength of steel, and can prevent the growth of crystal grains at high temperature to improve the welding performance of steel. The Nb element improves the creep strength of the steel, avoids hardening and tempering brittleness, and improves the low-temperature and high-temperature performance of the steel. The Cr element can improve the strength and hardness of steel and can also improve the corrosion resistance and oxidation resistance of the steel, if the content of the Cr element is less than 0.15 percent, the Cr element does not play a role in improving the strength of the steel, but can cause the waste of the addition of the alloy element with the content, if the Cr element is added too much, the strength of the steel is too high, the ductility and toughness are reduced, the alloy component which is added in a certain amount of excess is slightly improved on the strength of the steel, and the waste cost of the alloy element is too high. The addition of the elements can effectively exert the performance advantages of the steel used for the structural components of crane jib and other hoisting bearing forces.
And in the subsequent rolling process, the optimal performance of the steel is controlled by adopting a production process of increasing the reduction rate of a finishing mill set, adopting full cooling section cooling to increase the cooling rate and reducing the temperature of a coiling section in the laminar cooling stage.
Compared with the prior art, the technical scheme of the invention has the following advantages:
1) the structural hot rolled steel plate for the structural parts for lifting bearing capacity such as the 900 MPa-level hot rolled high-strength crane boom and the like has stable components on chemical elements, and has high strength, good plastic toughness and good welding performance.
2) The steel plate produced by the method has the mechanical properties that the yield strength reaches more than 800MPa and the tensile strength reaches more than 900MPa, specifically, the yield strength is 820-860 MPa and the tensile strength is 910-990 MPa; the elongation is more than or equal to 21 percent, the Charpy impact toughness impact energy at minus 20 ℃ is more than 84J, the cold bending d at 180 degrees is qualified as 2a, and the welding performance is good.
Drawings
FIG. 1 is a metallographic structure diagram of a steel material produced by the present invention;
FIG. 2 is a metallographic structure diagram of a steel material produced by the present invention;
FIG. 3 is a cold bending test (positive bending) diagram of a steel material produced by the present invention;
FIG. 4 is a diagram of a cold bending test (back bending) of steel produced by the present invention;
FIG. 5 is a metallographic structure diagram of a weld zone, a fusion zone, a coarse grain zone and a fine grain zone of a steel material produced by the present invention.
Detailed Description
The present invention will be described in detail with reference to examples.
The chemical compositions and weight percentages of the hot-rolled high-strength structural steel for crane arms of examples 1 to 5 are shown in table 1.
TABLE 1
The production method of the 900 MPa-level hot-rolled high-strength structural steel for crane boom in examples 1 to 5 includes the steps of:
1) slagging off before and after molten iron pretreatment is required;
2) strengthening slag blocking work of tapping at a converter production place, and carrying out deoxidation alloying in a slag tapping process;
3) adding aluminum particles into the alloy fine adjustment station and carrying out strong stirring to carry out primary reduction on the top slag;
4) FeTi70 is used at the LF furnace, and the total weak stirring time before and after the calcium feeding is ensured to be more than 15 min;
5) controlling the target temperature of the tundish in the continuous casting area to be 30 ℃ above the liquidus temperature;
6) the casting blanks of the steel grades require stacking and slow cooling treatment, the red blanks need to be stacked in time, the slow cooling time is 96 hours, and the casting blanks need to be checked after 96 hours;
7) the casting blank is cold-charged into a furnace, and the in-furnace time is 4 hours; controlling the discharging temperature of the steel billet according to 1300 ℃;
8) target thickness of the intermediate blank of the plate coil: 60 mm;
9) the roughing mill pressing mode is a 3+5 mode, and the seven frames of the finishing mill are all put into use;
10) the reduction rate of the finishing mill group adopts a balanced distribution mode, the reduction of F4-F7 frames is properly increased by 35-25%, and the finish rolling compression ratio is more than or equal to 4.0;
11) cooling after rolling adopts a full-section laminar cooling mode, and the cooling speed is 40 ℃/S-45 ℃/S;
12) the soaking temperature is 1300 ℃, the finish rolling target temperature is 850 ℃, and the coiling position target temperature is 550 ℃.
The specific process parameter control in each example is shown in table 2.
TABLE 2
The tensile, impact and cold bending tests were carried out on the 900MPa hot-rolled high-strength structural steel for crane boom in the examples, and the results are shown in Table 3.
TABLE 3
The 900 MPa-grade hot-rolled high-strength structural steel plate for the crane boom adopts a steel group which reduces C and controls Si and is added with Nb, Mo, Ti and Cr elements, has stable components on chemical elements, and has higher strength, good ductility and toughness and good welding performance compared with a comparative example in performance.
The metallographic structure of the structural steel for the hot-rolled high-strength crane boom of 900MPa grade prepared by the invention is shown in fig. 1 and 2, and the metallographic structure of the structural steel comprises acicular ferrite, granular bainite and a small amount of tempered martensite, wherein the percentages of the granular bainite and the tempered martensite are respectively 45% -40% and 15% -10%, and the grain size grade of the granular bainite and the tempered martensite is 8 grade. The existence of martensite structure increases the hardness of the material to a certain extent, and increases the resistance to deformation, cracking and abrasion, and the bainite is a non-laminated mixed structure of ferrite and carbide, so that the strength and the plasticity and toughness of the material are matched. Fine crystal grains, and the welding performance of the material is improved.
The steel plate produced by the method has the mechanical properties that the yield strength reaches more than 800MPa, the tensile strength is more than 900MPa, the elongation reaches more than 20 percent, the Charpy impact energy at minus 20 ℃ is more than 80J, and the 180-degree cold bending d-2 a is all qualified under the condition that the elongation and the Charpy impact energy at minus 20 ℃ meet the requirements, and the yield strength and the tensile strength of the steel plate are obviously superior to those of a comparative example. .
Through cold bending and observation experiments of a welding line area, as shown in fig. 5, firstly, by observing the metallographic structure of the welding line area, the metallographic structures of a base metal area, the welding line area and the welding line fusion area are in good transition fusion, and cracks on the surface, the root and the cross section of the welding line are all 0; secondly, as can be seen from the cold bending test results of the weld zone, as shown in fig. 3 and 4, the forward bending and the back bending are both good, no crack occurs, and the welding cold bending performance is good. And the impact energy of the welding seam at the temperature of-20 ℃ in the welding seam area can reach more than 80J, and the cold bending performance and the joint toughness of the welding are good.
The above detailed description of the 900MPa class hot rolled high strength structural steel for crane boom and the method for producing the same with reference to the embodiments is illustrative and not restrictive, and several embodiments can be cited within the limits thereof, so that changes and modifications without departing from the general concept of the present invention shall fall within the scope of the present invention.
Claims (8)
1. The 900 MPa-grade hot-rolled high-strength structural steel for the crane boom is characterized by comprising the following chemical components in percentage by weight: 0.050-0.070% of C, 0.10-0.20% of Si, 1.70-1.90% of Mn, less than or equal to 0.020% of P, less than or equal to 0.010% of S, 0.020-0.060% of Als0.06-0.08% of Nb0.06-0.08% of Mo0.08-0.12% of Ti, 0.11-0.13% of Cr0.15-0.19% of Ti, and the balance of Fe and inevitable impurities.
2. The 900MPa grade hot-rolled high-strength structural steel for crane booms as claimed in claim 1, wherein the metallographic structure of the 900MPa grade hot-rolled high-strength structural steel for crane booms is acicular ferrite, granular bainite and tempered martensite, wherein the percentages of the granular bainite and the tempered martensite are about 45% -40% and 15% -10%, respectively, and the grain size grade is 8.
3. The production method of the 900 MPa-grade hot-rolled high-strength structural steel for crane boom according to claim 1 or 2, characterized in that the production method comprises the following steps: molten iron pretreatment → converter smelting → alloy fine tuning station → LF refining → continuous casting → casting blank heat treatment → controlled rolling and controlled cooling → leveling → transverse cutting → finished product; wherein, the casting blank requires stacking and slow cooling treatment, the red blank is stacked in time, and the slow cooling time is 96 hours.
4. The production method according to claim 3, wherein the casting blank is cold-charged into the furnace for a period of not less than 4 hours; the tapping temperature of the steel billet is controlled according to 1300 ℃.
5. The production method according to claim 3, wherein the roughing mill reduction mode is a 3+5 mode and the finishing mill seven stands are all put into use.
6. The production method of claim 3, wherein the reduction rate of the finishing mill group adopts a balanced distribution mode, the reduction of the F4-F7 frames is increased to 35-25%, and the finish rolling compression ratio is controlled according to 4.0.
7. The production method according to claim 3, wherein the post-rolling cooling adopts a full-stage laminar cooling mode at a cooling rate of 40 ℃/s to 45 ℃/s.
8. The production method according to claim 3, wherein the soaking temperature is 1300 ℃ to 1400 ℃, the finish rolling temperature is 850 ℃ to 900 ℃, and the coiling position temperature is 500 ℃ to 550 ℃.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911261948.1A CN110923549A (en) | 2019-12-10 | 2019-12-10 | 900 MPa-grade hot-rolled high-strength structural steel for crane boom and production method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911261948.1A CN110923549A (en) | 2019-12-10 | 2019-12-10 | 900 MPa-grade hot-rolled high-strength structural steel for crane boom and production method thereof |
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| CN111254360A (en) * | 2020-03-30 | 2020-06-09 | 武汉钢铁有限公司 | A kind of low deformation resistance high strength steel and its production method and application |
| CN111607737A (en) * | 2020-06-28 | 2020-09-01 | 马鞍山钢铁股份有限公司 | High-strength steel plate for large crude oil storage tank and production method thereof |
| CN112048659A (en) * | 2020-09-11 | 2020-12-08 | 上海大学 | High-strength high-ductility steel plate and preparation method thereof |
| CN112410676A (en) * | 2020-11-23 | 2021-02-26 | 马鞍山钢铁股份有限公司 | Hot-rolled low-carbon steel and production method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111254360A (en) * | 2020-03-30 | 2020-06-09 | 武汉钢铁有限公司 | A kind of low deformation resistance high strength steel and its production method and application |
| CN111607737A (en) * | 2020-06-28 | 2020-09-01 | 马鞍山钢铁股份有限公司 | High-strength steel plate for large crude oil storage tank and production method thereof |
| CN111607737B (en) * | 2020-06-28 | 2021-12-14 | 马鞍山钢铁股份有限公司 | High-strength steel plate for large crude oil storage tank and production method thereof |
| CN112048659A (en) * | 2020-09-11 | 2020-12-08 | 上海大学 | High-strength high-ductility steel plate and preparation method thereof |
| CN112410676A (en) * | 2020-11-23 | 2021-02-26 | 马鞍山钢铁股份有限公司 | Hot-rolled low-carbon steel and production method thereof |
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