CN116607074A - Steel for thin blank production of thick 390MPa high-toughness tubular pile and production method thereof - Google Patents

Steel for thin blank production of thick 390MPa high-toughness tubular pile and production method thereof Download PDF

Info

Publication number
CN116607074A
CN116607074A CN202310603122.9A CN202310603122A CN116607074A CN 116607074 A CN116607074 A CN 116607074A CN 202310603122 A CN202310603122 A CN 202310603122A CN 116607074 A CN116607074 A CN 116607074A
Authority
CN
China
Prior art keywords
percent
steel
toughness
thick
390mpa
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.)
Pending
Application number
CN202310603122.9A
Other languages
Chinese (zh)
Inventor
王杨
孔祥磊
张瑜
黄国建
徐烽
栗锐
翟永彬
董洋
黄明浩
张英慧
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Angang Steel Co Ltd
Original Assignee
Angang Steel Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Angang Steel Co Ltd filed Critical Angang Steel Co Ltd
Priority to CN202310603122.9A priority Critical patent/CN116607074A/en
Publication of CN116607074A publication Critical patent/CN116607074A/en
Pending legal-status Critical Current

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
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
    • B21B1/24—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process
    • B21B1/26—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process by hot-rolling, e.g. Steckel hot mill
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B15/00—Arrangements for performing additional metal-working operations specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • 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
    • 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
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
    • 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
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling
    • 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
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • 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
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
    • 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
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B15/00—Arrangements for performing additional metal-working operations specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B2015/0057—Coiling the rolled product
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B2261/00—Product parameters
    • B21B2261/02—Transverse dimensions
    • B21B2261/04—Thickness, gauge
    • 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
    • C21D2211/005—Ferrite
    • 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
    • C21D2211/009—Pearlite
    • 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)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

The invention relates to steel for producing a thick 390MPa high-toughness tubular pile by a thin blank and a production method thereof, wherein the steel for producing the thick 390MPa high-toughness tubular pile by the thin blank comprises the following chemical components in percentage by weight: 0.069 to 0.079 percent of C, 0.10 to 0.20 percent of Si, 1.15 to 1.22 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.015 percent of S, 0.015 to 0.030 percent of Als, 0.032 to 0.042 percent of Nb, 0.034 to 0.043 percent of Ti, and the balance of iron and unavoidable impurities. Can realize continuous casting and rolling of sheet billet (135-170 mm) to produce steel hot rolled coil plate for 390MPa high-strength and high-toughness tubular pile with thick specification (20-24 mm).

Description

Steel for thin blank production of thick 390MPa high-toughness tubular pile and production method thereof
Technical Field
The invention belongs to the technical field of metal material low-alloy hot rolled coils, and particularly relates to steel for producing a high-toughness tubular pile with a thickness of 390MPa from a thin blank and a production method thereof.
Background
Along with the development of Chinese economy and the promotion of town, various buildings and infrastructures are continuously developed and perfected, the tubular pile is widely applied as a common building material, and in order to ensure the larger bearing capacity and service safety of the tubular pile for the building, each large project has higher requirements on the thickness and the strength and the toughness of steel for the tubular pile.
The thickness of the continuous casting billet used in hot rolling in each large steel mill is generally more than 200mm, while the thickness of the continuous casting billet used in the invention is 135-170 mm, and the compression ratio is small, so the method has certain difficulty in producing a thick 390MPa hot rolled coil because of small strength and toughness contribution to the thick steel for the tubular pile, and the published data show that the toughness index of the current steel for the tubular pile is not high, and the strength and toughness index of the current steel for the tubular pile is difficult to completely meet engineering requirements.
The patent document is a high-strength thick-specification steel for tubular piles and a manufacturing method thereof, and the steel has the application number of CN200910251585.3, wherein the steel comprises 0.12 to 0.16 percent of C, 0.20 to 0.50 percent of Si, 1.3 to 1.5 percent of Mn, less than or equal to 0.010 percent of S, less than or equal to 0.015 percent of P, 0.020 to 0.030 percent of Nb and 0.015 to 0.040 percent of Al. The casting blank of the invention has 230mm, large compression ratio, high alloy cost by adopting Nb microalloying, high content of C and Si, and harm to the impact toughness of the product, and the yield strength of the product reaches 400MPa, but the impact energy at the temperature of minus 40 ℃ is only 150J.
Patent document of application number CN201310489482.7 discloses a corrosion-resistant steel for bridge pipe piles and a production method thereof, wherein the steel comprises the following components in percentage by weight: 0.07 to 0.13 percent of C, 0.3 to 0.65 percent of Si, 0.80 to 1.30 percent of Mn, 0.025 to 0.045 percent of P, less than or equal to 0.002 percent of S, 0.035 to 0.050 percent of V, 0.008 to 0.025 percent of Ti, 0.005 to 0.020 percent of Re and 0.006 to 0.012 percent of Zr. The S content in the invention is controlled lower, and the steelmaking cost is higher; the rare earth elements Re and Zr are contained, the alloy cost is higher, the yield strength of the product reaches 390MPa, but the impact energy at 0 ℃ is only more than 47J, and the actual engineering use is easy to fail.
Patent document CN201310407630.6 discloses a steel plate for 40-60 mm thick pipe piles and a production method thereof, and the patent contains descriptions of medium plates and does not relate to a production method of plate coils.
The paper "Q345 C_Hq molten steel cold welding test for Hangzhou Bay bridge pipe pile" ("iron and steel research" 2004.4, p 29-31) mentions that the steel plate for the pipe pile has high C (1.34%) and Mn (1.25% -1.35%) contents, serious segregation, low toughness and undescribed other elements addition and production process.
The paper "reasons for the generation of transverse cracks in multi-pass welding of wind power generation tubular pile S355 steel" ("welding" 2011.10, p 49-51) mentions a tubular pile steel with 86mm thickness, wherein the content of C (0.15%), si (0.3%) and Mn (1.56%) is higher, and noble metal Ni is added, so that the thickness, performance and production process of the product are not described.
The paper "structure and corrosion resistance of tubular pile steel for hydraulic engineering" ("Corrosion and protection" 2018.7, p 501-502) mentions 3 types of tubular pile steel, cu and Cr are adopted to be added singly or in combination, the yield strength can reach 339MPa at most, but the impact energy at 0 ℃ is only 90J at most, the practical application is easy to break and fail, and in addition, the paper does not describe the thickness and the production process of the product.
The paper 'study on the structure and corrosion resistance of the strength tubular pile steel' (heat processing technology 2018.6, p 56-57) mentions 3 tubular pile steels with different Cr contents, wherein the Cr contents are respectively 0.5, 1.0 and 1.5 percent, the Cr content is higher, and the product alloy cost is higher. Furthermore, the paper does not describe the product thickness, toughness index and production process.
The steel for the tubular pile, which is related to the publication, comprises a medium plate and a hot rolled coil, wherein the alloy design of the hot rolled coil product basically adopts high C and high Mn to ensure the strength of the product, and one or more of Nb, ti, cr, ni and Cu are added in a matching way; although the strength grade of the product is above 300MPa, the impact toughness is poor, most of impact tests are carried out at 0 ℃, and the impact energy is not high; in order to ensure the strength and toughness of the steel plate, the strength and toughness of the steel plate are generally improved by increasing the compression ratio and adding a large amount of alloy elements in the production process in the prior art, so that the slab for producing the hot rolled coil product is thicker, and the thickness is generally 200-230 mm. Through literature research, the prior published materials do not have a method for producing steel for 390 MPa-grade high-toughness tubular piles with thick specifications by using thin slabs.
Disclosure of Invention
The invention aims to provide steel for a thick-specification high-strength and high-toughness 390 MPa-grade high-toughness tubular pile and a production method thereof by adopting an economic and reasonable alloy design and matching proper production process, and can realize continuous casting and rolling of a thin slab (135-170 mm) to produce a thick-specification (20-24 mm) hot-rolled coil of the steel for the 390MPa high-strength and high-toughness tubular pile.
In order to achieve the above purpose, the invention is realized by adopting the following technical scheme:
the steel for the thick 390MPa high-toughness tubular pile is produced from thin billets and is characterized by comprising the following chemical components in percentage by weight: 0.069 to 0.079 percent of C, 0.10 to 0.20 percent of Si, 1.15 to 1.22 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.015 percent of S, 0.015 to 0.030 percent of Als, 0.032 to 0.042 percent of Nb, 0.034 to 0.043 percent of Ti, and the balance of iron and unavoidable impurities.
According to the invention, the components of 390MPa tubular pile steel are designed by adopting C-Mn-Nb-Ti alloy, grains are refined through Nb microalloying, the coiling temperature and the cooling speed are controlled by improving the finishing temperature, the strength is improved by utilizing the strengthening effect of TiC, the MnS content is reduced by adding Ti to improve the toughness, and a uniform and fine ferrite-pearlite (F-P) structure is obtained by a comprehensive component process, wherein the ferrite volume fraction is 4% -5%, so that the tubular pile steel has excellent toughness, and the main elements have the following functions and selection reasons:
c: the invention relates to a steel, which is the most main element next to iron in the steel, wherein C is the most economical element for improving the strength of the steel, but the toughness and the weldability of the steel are gradually deteriorated along with the improvement of the content of C, and the low carbon content design is the basic guarantee for ensuring the excellent toughness and good weldability of the steel for the tubular pile after being welded in a combined part in the construction industry.
Si: is an important reducing agent and deoxidizer in the steelmaking process, and for many materials in carbon steel, si is contained below 0.5%, the Si can obviously improve the strength of ferrite-pearlite structure types, but the high Si content can lose the plasticity and toughness of the materials, so that the Si content is controlled to be lower. Therefore, the Si content of the present invention is controlled to be 0.10% to 0.20%.
Mn: the Mn has the solid solution strengthening effect, can reduce the gamma-alpha transformation temperature, further refine ferrite grains, and in addition, the Mn is added in the invention, so that the transformation from ferrite to pearlite can be delayed, the pearlite content is reduced, the toughness of the product is beneficial, but the excessive Mn content can cause serious segregation and loss of the toughness of the material. Therefore, the manganese content is controlled to be 1.15-1.22 percent.
Nb: the niobium can improve the performance of steel through various strengthening mechanisms such as precipitation strengthening, phase change strengthening and the like, and the effect of refining grains can improve yield strength and impact toughness, reduce brittle transition temperature and benefit welding performance. But Nb is a noble element and the strengthening effect is no longer obvious after adding a certain amount. Therefore, the Nb content is controlled to be 0.032% -0.042%.
Ti: the high-strength TiN-based alloy is an extremely strong nitride forming element, and TiN is difficult to decompose at high temperature, so that stable and fine TiN particles can effectively prevent austenite from growing in the reheating process of a casting blank on one hand and improve the impact toughness of a welding heat affected zone on the other hand. In addition, the bonding capability of Ti and S is stronger than that of Mn, so that the MnS content can be reduced to a certain extent, and the impact toughness of the material is improved, but excessive Ti element content can form carbonitride with enlarged size, and the toughness is lost instead, and the precipitated TiC is tiny by being matched with proper finishing temperature and coiling temperature, so that the precipitation strengthening effect is realized. Therefore, the Ti element is added in the invention to compensate the loss of toughness caused by insufficient compression ratio, if the Ti content is too high, large-sized TiN with sharp corners is easy to form, and the toughness is lost, so the Ti content of the invention is 0.034-0.043 percent.
Als: deoxidizing element and proper amount of aluminum are added to form fine and dispersed AlN particles, which is favorable for refining grains and improving the toughness of steel. Therefore, the Als content of the invention is 0.015 to 0.030 percent.
P: the steel is extremely easy to highly segregate during molten steel solidification, a banded F-P structure can be formed, P can greatly reduce the benefits brought by C reduction in the steel for the tubular pile, the toughness of the steel is lost, and the steel is required to be used as less harmful elements as possible, but the cost is increased due to the excessively low requirement. Therefore, the P content of the present invention is controlled to be 0.020% or less.
S: the lower the steel, the better the toughness of the steel is generally desired, but the lower the requirement, the higher the production cost is. Therefore, S is less than or equal to 0.015 percent.
A production method for producing thick 390MPa high-toughness steel for tubular piles by using thin blanks relates to the following production process flow: molten iron pretreatment, converter smelting, external refining (LF+Ca treatment), continuous casting, slab heating, rolling, laminar cooling and coiling. Wherein:
1) Smelting continuous casting process: molten iron pretreatment, and converter smelting adopts top blowing or top-bottom combined blowing; the external refining adopts LF light desulfurization treatment and calcium treatment to control the quantity and shape of inclusions; continuous casting adopts a dynamic light pressure mode, and the thickness of the obtained casting blank is 135-170 mm;
2) The rolling process comprises the following steps: heating a continuous casting slab to 1174-1183 ℃ through a stepping heating furnace to enable Nb and Ti to be fully solid-solved, playing a role of precipitation strengthening in the subsequent rolling process, and then performing two-stage controlled rolling through a rough rolling and finishing mill group, wherein the rough rolling finishing temperature is 1012-1019 ℃; the finish rolling temperature is 845-852 ℃, then the finish rolling is carried out at the speed of 27.7-28.6 ℃/s to 596-608 ℃ by adopting a laminar cooling mode, and finally the coiling is carried out, the air cooling is carried out to room temperature, and the higher coiling temperature ensures the extensibility index of the thick product.
The steel hot rolled coil for 390 MPa-level piling pipe has excellent strength and toughness: the yield strength of the steel plate is 390-410 MPa, the tensile strength is more than or equal to 490MPa, and the elongation after fracture is more than or equal to 23%; charpy impact energy (average value of 3 samples) A at-60 DEG C kv ≥217J。
The thickness of the steel plate finished product is 20-24 mm.
Compared with the prior art, the method has the advantages that the compression ratio is small, and the method has small contribution to the toughness of the steel for the thick tubular pile, so that the production of the thick 390 MPa-grade hot rolled coil has certain difficulty, and the defects of the insufficient compression ratio on the control of the toughness index are overcome through the technical work of the following second and third aspects, and the method has the beneficial effects that:
1) The invention adopts the sheet billet with 135-170 mm to roll the steel plate coil for the high-strength and high-toughness 390 MPa-level tubular pile with thick specification (20-24 mm), thereby improving the production efficiency and saving the production resources;
2) In the aspect of alloy design, the invention adopts C-Mn-Nb-Ti series alloy design, respectively adopts low C design to reduce the pearlite content, adds Mn to delay pearlite transformation and improve toughness, and adds Nb in proper amount to mainly exert the function of refining grains so as to improve toughness, and Ti is added to inhibit MnS from forming so as to improve toughness, and on the other hand, the invention combines a rolling process to exert TiC precipitation strengthening function so as to improve strength, thereby guaranteeing excellent toughness index of the product;
3) In the aspect of rolling technology, by combining the alloy design, a casting blank is heated to 1174-1183 ℃, the solid solubility of Nb can be improved by adding Ti, the strengthening effect of Nb and Ti can be fully exerted in the subsequent rolling process, high-temperature large-deformation rolling is adopted in the rough rolling stage, recrystallization refinement structure is continuously generated, and the higher coiling temperature ensures the extensibility index of thick-specification products;
4) The alloy of the product has the advantages of economical and reasonable design, simple and stable process route, easy execution, excellent physical quality of the product, 390-410 MPa of steel plate yield strength, more than or equal to 490MPa of tensile strength and more than or equal to 23% of elongation after fracture; charpy impact energy (average value of 3 samples) Akv is larger than or equal to 217J at minus 60 ℃.
Detailed Description
The present invention will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
The following examples are provided to illustrate the present invention and are not intended to limit the invention. The chemical compositions of the steel examples of the invention are shown in Table 1, the rolling process schedule of the steel examples of the invention is shown in Table 2, and the mechanical properties of the steel examples of the invention are shown in Table 3.
Table 1 example chemical composition (wt.%)
Table 2 example steel process schedule
TABLE 3 Main mechanical Properties of example steels

Claims (5)

1. The steel for the thick 390MPa high-toughness tubular pile is produced from thin billets and is characterized by comprising the following chemical components in percentage by weight: 0.069 to 0.079 percent of C, 0.10 to 0.20 percent of Si, 1.15 to 1.22 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.015 percent of S, 0.015 to 0.030 percent of Als, 0.032 to 0.042 percent of Nb, 0.034 to 0.043 percent of Ti, and the balance of Fe and unavoidable impurities.
2. The steel for producing thick 390MPa high-toughness pipe piles from thin slabs according to claim 1, wherein the structure in the steel is ferrite-pearlite, wherein the volume fraction of ferrite is 4-5%.
3. The steel for producing thick 390MPa high-toughness tubular piles by using the thin blank according to claim 1, wherein the yield strength of the steel plate is 390-410 MPa, the tensile strength is more than or equal to 490MPa, and the elongation after fracture is more than or equal to 23%; charpy impact energy A at-60 DEG C kv ≥217J。
4. The steel for producing 390MPa thick high-toughness tubular piles from thin blanks according to claim 1, wherein the thickness of the steel plate is 20-24 mm.
5. A method for producing a steel for a thick 390MPa high-toughness tubular pile from a thin blank according to any one of claims 1 to 4, comprising:
the thickness of the continuous casting slab is 135-170 mm, the continuous casting slab is heated to 1174-1183 ℃ by a heating furnace, then is rolled by a rough rolling and finishing mill group in two stages, and the final rolling temperature of rough rolling is 1012-1019 ℃; the finish rolling temperature is 845-852 ℃, then the finish rolling is carried out at the speed of 27.7-28.6 ℃/s to 596-608 ℃ by adopting a laminar cooling mode, and finally the coiling is carried out, and finally the coiling is cooled to room temperature.
CN202310603122.9A 2023-05-26 2023-05-26 Steel for thin blank production of thick 390MPa high-toughness tubular pile and production method thereof Pending CN116607074A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310603122.9A CN116607074A (en) 2023-05-26 2023-05-26 Steel for thin blank production of thick 390MPa high-toughness tubular pile and production method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310603122.9A CN116607074A (en) 2023-05-26 2023-05-26 Steel for thin blank production of thick 390MPa high-toughness tubular pile and production method thereof

Publications (1)

Publication Number Publication Date
CN116607074A true CN116607074A (en) 2023-08-18

Family

ID=87676141

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310603122.9A Pending CN116607074A (en) 2023-05-26 2023-05-26 Steel for thin blank production of thick 390MPa high-toughness tubular pile and production method thereof

Country Status (1)

Country Link
CN (1) CN116607074A (en)

Similar Documents

Publication Publication Date Title
CN111455255B (en) Preparation method of EH36 steel for extra-thick offshore wind power with thickness of 80-100mm
CN110777296B (en) Ultra-thick X52 pipeline steel hot-rolled coil and production method thereof
CN114645183B (en) Production method of high-toughness low-yield-ratio low-alloy high-strength steel plate
CN111235464B (en) Titanium microalloyed economical high-strength weathering steel and production method thereof
CN112553532A (en) High-toughness reduced ship plate marine steel and preparation method thereof
CN102839320B (en) High-heat input steel plate for welding and manufacturing method thereof
CN112226673A (en) Hot rolled steel plate with 650 MPa-grade tensile strength and manufacturing method thereof
CN113430458A (en) Ultrahigh-strength steel plate with yield strength of more than 1040MPa and manufacturing method thereof
CN112553524A (en) Hot rolled steel plate with yield strength of 360MPa for pipeline and manufacturing method thereof
CN113802060A (en) Low-cost steel plate for engineering structure and manufacturing method thereof
CN113846269A (en) Cold-rolled high-weather-resistance steel plate with high strength and plasticity and preparation method thereof
CN101519752A (en) High strength and toughness pipeline steel roll in low-carbon and high-niobium-chromium system and preparation method thereof
CN116752056B (en) High-strength and high-toughness low-yield-ratio longitudinal variable-thickness weather-resistant bridge steel and manufacturing method thereof
CN114231826B (en) Production method of Q420qE bridge structural steel plate
CN114480976A (en) High-temperature rolled Q420qE bridge structural steel plate and production method thereof
CN110669990B (en) High-performance chromium-molybdenum steel plate and production method thereof
CN116607074A (en) Steel for thin blank production of thick 390MPa high-toughness tubular pile and production method thereof
CN115074639A (en) Hot-rolled steel plate for automobile beam with tensile strength of 600MPa
CN116607073A (en) Steel for producing thick 430MPa high-toughness tubular pile from thin blank and production method
CN116607075A (en) Steel for producing thick 355MPa high-toughness tubular pile from thin blank and production method
CN116752037A (en) Steel for producing thick 270MPa high-toughness tubular pile from thin blank and production method
CN116640990A (en) Steel for producing thick 320MPa high-toughness tubular pile from thin blank and production method
CN116623087A (en) Steel for producing thick 240MPa high-toughness tubular pile from thin blank and production method
CN115852246B (en) Boron-containing hot rolled steel plate for welded gas cylinders and manufacturing method thereof
CN116770190B (en) Low-yield-ratio longitudinal variable-thickness bridge steel 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