[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

CN118166287A - High-strength steel for high heat input welding and manufacturing method thereof - Google Patents

High-strength steel for high heat input welding and manufacturing method thereof Download PDF

Info

Publication number
CN118166287A
CN118166287A CN202410430104.XA CN202410430104A CN118166287A CN 118166287 A CN118166287 A CN 118166287A CN 202410430104 A CN202410430104 A CN 202410430104A CN 118166287 A CN118166287 A CN 118166287A
Authority
CN
China
Prior art keywords
heat input
high heat
input welding
steel
rolling
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
CN202410430104.XA
Other languages
Chinese (zh)
Inventor
丁庆丰
陈德才
吴腊珍
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.)
Hubei University of Automotive Technology
Original Assignee
Hubei University of Automotive Technology
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 Hubei University of Automotive Technology filed Critical Hubei University of Automotive Technology
Priority to CN202410430104.XA priority Critical patent/CN118166287A/en
Publication of CN118166287A publication Critical patent/CN118166287A/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
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • 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
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/1206—Accessories for subsequent treating or working cast stock in situ for plastic shaping of strands
    • 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
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/128—Accessories for subsequent treating or working cast stock in situ for removing
    • 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
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/0006—Adding metallic additives
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/06—Deoxidising, e.g. killing
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/064—Dephosphorising; Desulfurising
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/10—Handling in a vacuum
    • 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
    • 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
    • C22C33/06—Making ferrous alloys by melting using master alloys
    • 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
    • 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
    • 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)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

The invention discloses high-strength steel for high heat input welding and a manufacturing method thereof. The steel comprises the chemical components of ：C:0.11～0.15％、Si:0.15～0.45％、Mn:1.65～1.95％、Ti:0.030～0.050％、V:0.020～0.050％、Als≤0.008％、N≤0.0050％、Cr≤0.10％、P≤0.015％、S≤0.005％, and the balance of Fe and unavoidable impurity elements. The free O content is controlled in the smelting process, the formation of TiOx is better promoted, and the thin and dispersed TiOx-containing composite oxide is formed in the casting blank and the steel plate, so that the prior austenite grains are prevented from growing in the heating process of the casting blank, and the effect of refining the grains is achieved. In the process of high heat input welding, the composite oxides promote acicular ferrite to form, so as to achieve the effect of inhibiting coarsening of crystal grains in a welding heat affected zone, improve the low-temperature toughness of the welding heat affected zone with high heat input at-40 ℃, and enable the steel to have the characteristic of high heat input welding resistance. By controlling the low S content and Ti oxide, the long-strip MnS caused by the higher Mn content is modified into a short rod shape or a round shape, and the shape, the size and the distribution of the inclusions are improved by the modification of the inclusions, so that the low-temperature toughness of the steel is improved.

Description

High-strength steel for high heat input welding and manufacturing method thereof
Technical Field
The invention relates to the technical field of metal metallurgy, in particular to high-strength steel for high heat input welding and a manufacturing method thereof.
Background
With the gradual maturity of the electro-gas welding technology, the electro-gas welding technology is widely applied to various industries such as high-rise buildings, bridges, large ships, containers, pressure containers and the like, so that the labor intensity of workers is obviously reduced, and the working efficiency is improved. However, with the gradual complexity of the use environment and the increasing competition of cost, the existing steel grade is difficult to meet the requirements of high heat input welding resistance and low temperature toughness.
Disclosure of Invention
The invention provides high-strength steel for high heat input welding and a manufacturing method thereof, which can simultaneously meet the requirements of high heat input welding resistance and low-temperature toughness.
The invention provides high-strength steel for high heat input welding resistance and a manufacturing method thereof.
One or more technical schemes provided by the invention have at least the following technical effects or advantages:
the component design of the high-strength steel for high heat input welding provided by the invention is based on C+Mn system, only Ti and V microalloying is added, mnS is modified by the weak oxidizing atmosphere of molten steel, fine high-temperature composite oxide containing TiO x is formed, grains are refined, and the low-temperature toughness and high heat input welding performance of super-thick building steel can be improved. Specifically, through reasonable collocation of C, mn elements, the strength of the extra-thick plate is improved, the low-temperature toughness of the extra-thick plate can be controlled, and the occurrence of the condition that the weldability is influenced due to the fact that the carbon equivalent is too high can be prevented. Considering the performance requirements comprehensively, the content of C is 0.10-0.14%, and the content of Mn is 1.65-1.90%.
In addition, si can improve the strength of steel sheets and welded joints, but too high thereof affects the low-temperature toughness and surface quality of steel, so the content of Si is 0.10 to 0.45%.
P, S, N is unavoidable as an impurity element in steel, but is detrimental to weldability, low-temperature toughness, hot workability, etc. of steel sheets, and therefore, the lower the content is, the better the content is, the less than 0.015%, the less than 0.005% of S, and the less than 0.005% of N.
Al is an important deoxidizing element, a large amount of Al 2O3 inclusions are easily formed in steel to influence the quality and performance of the steel, al material is not used for deoxidizing to avoid influencing the formation of Ti oxide, silicon, manganese and titanium are used for deoxidizing for secondary deoxidizing, and the content of Als is strictly controlled to be less than or equal to 0.008 percent.
V is an important microalloying element which can react with C, N to form a carbon nitrogen compound, and is separated out in the stacking slow cooling process after the steel plate is rolled, so that the strength of the super-thick steel is improved, and the low-temperature toughness of the super-thick steel is improved, and therefore, the V content is 0.020-0.050%.
Ti is added when a certain free O element exists in molten steel, forms Ti 2O3 oxide with the free O element, has higher melting point of Ti 2O3, is finely dispersed and distributed in a casting blank, can prevent coarsening of prior austenite when the casting blank is heated, and is used as a nucleation core to promote acicular ferrite to form in the high heat input welding process of the steel plate, so that grains of a welding heat affected zone are further refined, and the low-temperature toughness of the welding heat affected zone is improved. However, excessive amounts of Ti and O deteriorate the low temperature toughness of the steel sheet and the weld heat affected zone. Therefore, the Ti content is 0.030 to 0.050%.
In summary, the high-strength steel for large-line energy welding provided by the invention adopts a low-carbon component design, is assisted with trace Ti oxide metallurgy, strictly controls the free [ O ] content at each stage in the smelting process, controls the ferrotitanium adding sequence and nodes so as to better promote the formation of TiOx, and forms tiny and dispersed TiOx-containing composite oxides in casting blanks and steel plates, wherein the TiOx-containing composite oxides not only prevent the growth of original austenite grains in the heating process of the casting blanks, but also play a role in refining the grains. In the process of large heat input welding, the dispersed TiOx-containing composite oxides promote acicular ferrite to form, so that the effect of inhibiting coarsening of crystal grains in a welding heat affected zone is achieved, and the crystal grains in the welding heat affected zone are refined, thereby obviously improving the low-temperature toughness of the welding heat affected zone with large heat input at-40 ℃, and the high-strength steel for welding with large heat input resistance has the characteristic of welding with large heat input resistance. The invention realizes the purpose of improving the low-temperature toughness of the high-strength steel for high heat input welding by strictly controlling the low S content (less than or equal to 0.005%wt) and Ti oxide metallurgy, so that the long-strip MnS caused by the higher Mn content is modified into a short rod shape or a round shape, and the shape, the size and the distribution of the inclusions are improved through the modification of the inclusions. And after the ACC weak cooling is finished, the high-strength steel plate with the thickness of 90-100mm is rapidly subjected to off-line stacking and slow cooling, so that the off-line temperature of the surface of the steel plate is not lower than 400 ℃, and the second phase V (C, N) is promoted to be separated out in the process of the steel plate stacking and slow cooling, thereby further improving the toughness matching of the super-thick steel plate.
Drawings
FIG. 1 is a flow chart of a method for manufacturing high-strength steel for high heat input welding according to an embodiment of the present invention;
FIG. 2 is a schematic view of the microstructure of the surface layer of a steel sheet obtained by the example of the present invention;
FIG. 3 is a schematic diagram of the structure of a 200KJ/cm large heat input weld heat affected zone of a steel plate obtained by an example of the present invention, and the result of analysis of a typical Ti-containing composite oxide energy spectrum.
Detailed Description
The embodiment of the invention can simultaneously meet the requirements of high heat input welding resistance and low-temperature toughness by providing the high-strength steel for high heat input welding resistance and the manufacturing method thereof.
In order to better understand the above technical solutions, the following detailed description will refer to the accompanying drawings and specific embodiments.
The high-strength steel for high heat input welding provided by the embodiment of the invention comprises the following chemical components in percentage by weight (wt%) and the balance of ：C:0.11～0.15％、Si:0.15～0.45％、Mn:1.65～1.95％、Ti:0.030～0.050％、V:0.020～0.050％、Als≤0.008％、N≤0.0050％、Cr≤0.10％、P≤0.015％、S≤0.005％, Fe and unavoidable impurity elements.
Specifically, the yield strength R eL is more than or equal to 420MPa, the tensile strength R m is more than or equal to 550MPa, the yield ratio is less than or equal to 0.80, the elongation A is more than or equal to 23%, the impact toughness is more than or equal to 100J at-40 ℃ KV 2, and the impact toughness of a large heat input welding heat affected zone is less than or equal to 200KJ/cm and is more than or equal to 47J at-40 ℃ KV 2. The thickness of the steel ranges from 90 to 100mm.
Referring to fig. 1, the method for manufacturing high-strength steel for high heat input welding provided by the embodiment of the invention comprises the following steps:
step S110: smelting and continuously casting the high-strength steel for high heat input welding according to the chemical components of the high-strength steel for high heat input welding to obtain a casting blank;
the specific explanation of this step is that the casting blank is obtained by smelting and continuously casting the chemical components of the high-strength steel for high heat input welding, which comprises the following steps:
Pretreating blast furnace molten iron, smelting molten iron with the content of [ S ] being less than or equal to 0.003 percent in a converter, deeply dephosphorizing in the converter, ensuring the content of [ P ] being less than or equal to 0.012 percent in tapping, adding ferrosilicon and ferromanganese to adjust the content of Si and Mn and deoxidizing during tapping, and not adopting aluminum-containing materials such as aluminum particles, aluminum wires, aluminum ingots and the like to deoxidize; adding manganese alloy and ferrovanadium to adjust Si, mn and V contents during refining in an LF ladle furnace; when [ O ] is 0.0020-0.0040%, adding Ti alloy, and refining without deoxidizing aluminum-containing materials such as aluminum wire; then degassing in an RH vacuum furnace; and the continuous casting adopts argon protection casting and soft reduction technology, and is cast into a casting blank with the thickness of 450mm, and the casting blank is stacked and slowly cooled for at least 24 hours.
Step S120: heating the casting blank;
The specific explanation of this step, heating the casting blank, includes:
The blank is hot-fed, and the surface temperature of the blank is not more than 500 ℃ during hot charging, and the soaking section temperature of the heating furnace is 1200-1260 ℃.
Step S130: rolling the heated blank, and after finishing rolling, adopting ACC cooling water for weak cooling, wherein the reddening temperature is 650-700 ℃;
Specifically, rolling the heated billet comprises:
Adopting a two-stage rolling method, wherein the first-stage cross rolling widens and longitudinal rolling is performed to the bottom, so that the single pass rolling reduction is not lower than 45mm when at least 2 passes of longitudinal rolling is performed, and the final rolling temperature is 980-1030 ℃; the second stage rolling temperature is 830-860 deg.c and the final rolling temperature is 800-830 deg.c.
Step S140: the steel plates are rapidly cooled down by stacking and slow cooling, and are piled and cooled for at least 48 hours.
The present invention will be described in further detail with reference to specific examples.
The high-strength steel plate for high heat input welding provided by the embodiment of the invention has the thickness of 90mm and 100mm and comprises the following chemical components in percentage by weight: c:0.13%, si:0.26%, mn:1.68%, P:0.010%, S:0.001%, ti:0.035%, V:0.032%, als:0.004%, N:0.0036%.
(1) Smelting continuous casting process: pretreating blast furnace molten iron, smelting molten iron with the content of [ S ] being less than or equal to 0.003 percent in a converter, deeply dephosphorizing in the converter, ensuring the content of [ P ] being less than or equal to 0.012 percent in tapping, adding ferrosilicon and ferromanganese to adjust the content of Si and Mn and deoxidizing during tapping, and not adopting aluminum-containing materials such as aluminum particles, aluminum wires, aluminum ingots and the like to deoxidize; when the LF ladle furnace is refined, a proper amount of manganese alloy and ferrovanadium can be added to adjust the contents of Si, mn and V, and when the content of [ O ] is 0.0020-0.0040%, ti alloy is added, and aluminum-containing materials such as aluminum wires and the like are not required to be deoxidized in the refining process; then degassing in an RH vacuum furnace; and the continuous casting adopts argon protection casting and soft reduction technology, and is cast into a casting blank with the thickness of 450mm, and the casting blanks are stacked and slowly cooled for 36 hours.
(2) The heating and rolling process comprises the following steps: the blank is hot-fed, and the surface temperature of the blank is 425 ℃ and the soaking section temperature of the heating furnace is 1240-1250 ℃ during hot charging. The controlled rolling adopts two-stage rolling, the first-stage cross rolling widens and longitudinal rolling is performed to the bottom, the single pass rolling reduction is ensured to be 46 mm-50 mm when at least 2 passes of longitudinal rolling are performed, and the final rolling temperature is 990-1010 ℃; the second stage is to roll the steel plate with the thickness of 90mm and 100mm at the initial temperature of 820-840 ℃ and the final temperature of 810-830 ℃.
(3) And (3) a controlled cooling and stacking cooling process: and after finishing rolling, adopting ACC cooling water for weak cooling, wherein the reddening temperature is 660-680 ℃, and rapidly taking the steel plates off line for stacking and slow cooling, and stacking and cooling for 60 hours.
The microstructure of the surface layer of the steel plate obtained by the embodiment of the invention is shown in fig. 2, and the microstructure is ferrite and pearlite. The structure diagram of the 200KJ/cm large heat input welding heat affected zone of the steel plate obtained by the embodiment of the invention and the energy spectrum analysis result of the typical Ti-containing composite oxide are shown in FIG. 3. The typical Ti-containing composite oxide has a size of about 2um and shows a nucleation core state of acicular ferrite in a welding heat affected zone, and the fine distributed Ti-containing composite oxide is favorable for the formation of the acicular ferrite, can refine grains of the welding heat affected zone and improve the low-temperature toughness of the welding heat affected zone.
The tensile and impact properties of the steel sheet of the example of the present invention were measured by sampling 10mm longitudinally under the surface layer and performing mechanical property detection, as shown in Table 1.
TABLE 1
Therefore, the performance of the steel plate provided by the embodiment of the invention meets the index requirements that the yield strength R eL is more than or equal to 420MPa, the tensile strength R m is more than or equal to 550MPa, the yield ratio is less than or equal to 0.80, the elongation A is more than or equal to 23%, and the impact toughness is more than or equal to minus 40 ℃ KV 2 is more than or equal to 100J.
The steel plate of the embodiment of the invention is longitudinally sampled and processed into a welding thermal simulation sample of 11mm multiplied by 90mm, and different line energy welding thermal simulation tests are carried out on a Gleeble-3500 thermal-mechanical simulation test machine, and after the test is finished, the tensile and impact samples are processed for tensile and low-temperature impact tests. Table 2 shows the low temperature impact data for weld heat affected zones at-40℃for the examples of the present invention under different line energies.
TABLE 2
As can be seen from the test results in Table 2, the impact toughness of the steel plate provided by the embodiment of the invention in a welding heat affected zone meets the standard requirement that KV 2 is more than or equal to 47J at-40 ℃, and has a larger margin.
The steel plate provided by the embodiment of the invention has the characteristics of high strength, excellent low-temperature toughness, excellent large heat input welding resistance and the like, and has the advantages of short production process flow, low production cost, strong operability and good market prospect.
Embodiments of the present invention are not described in detail and are well known to those skilled in the art. Finally, it is noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made thereto without departing from the spirit and scope of the technical solution of the present invention, which is intended to be covered by the scope of the claims of the present invention.

Claims (7)

1. A high-strength steel for high heat input welding is characterized by comprising the following chemical components in percentage by weight, wherein the balance of ：C:0.11～0.15％、Si:0.15～0.45％、Mn:1.65～1.95％、Ti:0.030～0.050％、V:0.020～0.050％、Als≤0.008％、N≤0.0050％、Cr≤0.10％、P≤0.015％、S≤0.005％, is Fe and unavoidable impurity elements.
2. The high-strength steel for high heat input welding according to claim 1, wherein the steel has a yield strength R eL of not less than 420MPa, a tensile strength R m of not less than 550MPa, a yield ratio of not less than 0.80, an elongation A of not less than 23%, an impact toughness of not less than 40 ℃ KV 2 of not less than 100J, an impact toughness of not more than 200KJ/cm in a high heat input welding heat affected zone of not less than 40 ℃ KV 2 of not less than 47J.
3. High-strength steel for high heat input welding according to claim 1, wherein the thickness of the steel is in the range of 90-100mm.
4. A method for manufacturing high-strength steel for high heat input welding, comprising the steps of:
smelting and continuously casting the chemical composition of the high-strength steel for high heat input welding according to any one of claims 1 to 3 to obtain a casting blank;
Heating the casting blank;
Rolling the heated blank, and after finishing rolling, adopting cooling water for weak cooling, wherein the reddening temperature is 650-700 ℃;
The steel plates are rapidly cooled down by stacking and slow cooling, and are piled and cooled for at least 48 hours.
5. The method for manufacturing high-strength steel for high heat input welding according to claim 4, wherein the continuous casting of the chemical components of the high-strength steel for high heat input welding according to any one of claims 1 to 3 comprises:
pretreating blast furnace molten iron, smelting molten iron with the content of [ S ] being less than or equal to 0.003 percent in a converter, deeply dephosphorizing in the converter, ensuring the content of [ P ] being less than or equal to 0.012 percent in tapping, adding ferrosilicon and ferromanganese to adjust the content of Si and Mn during tapping, and deoxidizing; adding manganese alloy and ferrovanadium to adjust Si, mn and V contents during refining in an LF ladle furnace; adding Ti alloy when [ O ] is 0.0020-0.0040%; then degassing in an RH vacuum furnace; and the continuous casting adopts argon protection casting and soft reduction technology, and is cast into a casting blank with the thickness of 450mm, and the casting blank is stacked and slowly cooled for at least 24 hours.
6. The method for manufacturing high-strength steel for high heat input welding according to claim 4, wherein said heating said cast slab comprises:
The blank is hot-fed, and the surface temperature of the blank is not more than 500 ℃ during hot charging, and the soaking section temperature of the heating furnace is 1200-1260 ℃.
7. The method for manufacturing high-strength steel for high heat input welding according to claim 4, wherein the rolling of the heated billet comprises:
Adopting a two-stage rolling method, wherein the first-stage cross rolling widens and longitudinal rolling is performed to the bottom, so that the single pass rolling reduction is not lower than 45mm when at least 2 passes of longitudinal rolling is performed, and the final rolling temperature is 980-1030 ℃; the second stage rolling temperature is 830-860 deg.c and the final rolling temperature is 800-830 deg.c.
CN202410430104.XA 2024-04-10 2024-04-10 High-strength steel for high heat input welding and manufacturing method thereof Pending CN118166287A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202410430104.XA CN118166287A (en) 2024-04-10 2024-04-10 High-strength steel for high heat input welding and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202410430104.XA CN118166287A (en) 2024-04-10 2024-04-10 High-strength steel for high heat input welding and manufacturing method thereof

Publications (1)

Publication Number Publication Date
CN118166287A true CN118166287A (en) 2024-06-11

Family

ID=91356843

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202410430104.XA Pending CN118166287A (en) 2024-04-10 2024-04-10 High-strength steel for high heat input welding and manufacturing method thereof

Country Status (1)

Country Link
CN (1) CN118166287A (en)

Similar Documents

Publication Publication Date Title
CN107151763B (en) Thin gauge is high-strength cold-formed to use hot rolled strip and its production method
US9771638B2 (en) Cold-rolled steel sheet
EP4089199B1 (en) Low temperature-resistant hot-rolled h-type steel for 355mpa marine engineering and preparation method therefor
CN107964624A (en) A kind of yield strength 500MPa level structure steel and preparation method thereof
CN106811684B (en) 750Mpa grades of container hot rolled steel plates of yield strength and its manufacturing method
CN114318140A (en) Pipeline steel with excellent acid resistance and manufacturing method thereof
CN113862559A (en) 520 MPa-grade low-yield-ratio wind power steel and preparation method thereof
CN113265502A (en) Preparation method of high-strength 550L automobile girder steel
CN115418553A (en) High-corrosion-resistance weathering steel and preparation method thereof
CN111321340A (en) Hot rolled steel plate with yield strength of 450MPa and manufacturing method thereof
JPH10226843A (en) Thin steel sheet small in defect and excellent in press formability and its production
JP3275783B2 (en) Method for producing Ti-added hot-rolled high-strength steel sheet excellent in formability
CN118166287A (en) High-strength steel for high heat input welding and manufacturing method thereof
JP4998365B2 (en) Ultra-low carbon steel sheet and manufacturing method thereof
CN108929987A (en) A kind of 460MPa grades of cold rolling micro-alloy high-strength steel and its manufacturing method
KR100856306B1 (en) Ferritic stainless steel having excellent low temperature formability of welded zone
JP2001020033A (en) Non-heattreated high tensile strength steel excellent in toughness of base material and weld heat-affected zone
JP2000256786A (en) Cold rolled steel sheet minimal in inplane anisotropy and excellent in baking hardenability and aging resistance
JP3739933B2 (en) Steel sheet for surface treatment with good workability and few defects and method for producing the same
KR101169510B1 (en) Cold-rolled steel sheet, galvannealed steel sheet and processes for production of both
CN118086651B (en) High Jiang Tehou steel plate and production method thereof
CN118086780B (en) Acid-resistant pipeline steel and manufacturing method thereof
JP2007177303A (en) Steel having excellent ductility and its production method
JP3474432B2 (en) Steel sheet for cans with few defects and small in-plane anisotropy and method for producing the same
JP3577383B2 (en) Steel sheet for cans with few defects and excellent bake hardenability and method for producing the same

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