CN115094331A - Low-cost Q690 steel plate and production method thereof - Google Patents

Low-cost Q690 steel plate and production method thereof Download PDF

Info

Publication number
CN115094331A
CN115094331A CN202210843516.7A CN202210843516A CN115094331A CN 115094331 A CN115094331 A CN 115094331A CN 202210843516 A CN202210843516 A CN 202210843516A CN 115094331 A CN115094331 A CN 115094331A
Authority
CN
China
Prior art keywords
steel plate
equal
cost
less
low
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
CN202210843516.7A
Other languages
Chinese (zh)
Inventor
钱学海
杨跃标
廖耀俊
叶姜
李显
李宗强
甘雯雯
黄日康
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.)
Guangxi Liugang Huachuang Technology R & D Co ltd
Liuzhou Iron and Steel Co Ltd
Original Assignee
Guangxi Liugang Huachuang Technology R & D Co ltd
Liuzhou Iron and 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 Guangxi Liugang Huachuang Technology R & D Co ltd, Liuzhou Iron and Steel Co Ltd filed Critical Guangxi Liugang Huachuang Technology R & D Co ltd
Priority to CN202210843516.7A priority Critical patent/CN115094331A/en
Publication of CN115094331A publication Critical patent/CN115094331A/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
    • 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent 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
    • C21D6/001—Heat treatment of ferrous alloys containing Ni
    • 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
    • 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
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
    • 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
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
    • 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

Abstract

The invention provides a low-cost Q690 steel plate and a production method thereof, wherein the production method of the Q690 steel plate comprises the following process steps which are sequentially carried out: heating by a heating furnace, removing phosphorus by high-pressure water, rough rolling, cooling, finish rolling, straightening by a pre-straightening machine, electromagnetic induction heating, quenching, hot straightening, cooling by a cooling bed and tempering heat treatment. The Q690 structural steel plate comprises the following chemical components in percentage by weight: c: 0.12-0.18%, Si is less than or equal to 0.45%, Mn: 1.45-1.60%, P is less than or equal to 0.020%, S is less than or equal to 0.010%, Alt: 0.02 to 0.040%, Nb: 0.045-0.06%, Ti: 0.015 to 0.025%, B: 0.0025-0.0040%, N: 0.0040-0.0065 percent of carbon equivalent CEV, less than or equal to 0.44 percent of carbon equivalent CEV, and the balance of Cu, Ni and As, less than or equal to 0.80 percent and 0.080 percent. The invention effectively reduces the production cost of the Q690 steel plate, and has low energy consumption and high production efficiency.

Description

Low-cost Q690 steel plate and production method thereof
Technical Field
The invention relates to the field of metallurgy, in particular to a Q690 steel plate and a production method thereof, and especially relates to a low-cost Q690 steel plate and a production method thereof.
Background
At present, with the lighter weight and larger size of products in industries such as engineering machinery and the like, more and more high-strength medium plate products such as Q690 and the like are used, and most of the high-strength medium plate products in the industries are produced by adding a large amount of alloy elements such as Ni, Cr, Mo, V and the like and performing quenching and tempering treatment, so that the cost is higher and the production period is longer.
In summary, the following problems exist in the prior art: the Q690 steel plate is high in production cost and long in production period.
Disclosure of Invention
The invention provides a Q690 steel plate and a production method thereof, in particular to a low-cost Q690 steel plate and a production method thereof, and aims to solve the problems that the Q690 steel plate is high in production cost and long in production period.
Therefore, the invention provides a production method of a low-cost Q690 steel plate, and the content ratio of chemical components of the low-cost Q690 steel plate is C: 0.12-0.18%, Si is less than or equal to 0.45%, Mn: 1.45-1.60%, P is less than or equal to 0.020%, S is less than or equal to 0.010%, Alt: 0.02 to 0.040%, Nb: 0.045-0.06%, Ti: 0.015-0.025%, B: 0.0025-0.0040%, N: 0.0040 to 0.0065 percent of carbon equivalent CEV which is less than or equal to 0.44 percent, and the balance of Cu which is less than or equal to 0.80 percent, Ni which is less than or equal to 0.80 percent and As which is less than or equal to 0.080 percent;
the production method of the low-cost Q690 steel plate comprises the following process steps which are sequentially carried out: heating by a heating furnace, removing phosphorus by high-pressure water, rough rolling, cooling, finish rolling, straightening by a pre-straightening machine, electromagnetic induction heating, quenching, hot straightening, cooling by a cooling bed and tempering heat treatment.
In the rough rolling stage, the single-pass reduction rate is increased, and the final reduction rate of 2-3 passes is more than 20%; and in the finish rolling stage, increasing the single-pass reduction rate, wherein the pass reduction rate is more than 10%, discharging the steel plate out of a finish rolling unit, measuring the surface temperature of the steel plate through a pre-straightening machine to form a temperature curve, adjusting the heating power according to the surface temperature curve of the steel plate, and controlling the surface temperature to be uniform.
Further, the thickness of the steel plate is 6-50 mm.
Furthermore, the heating time of the heating furnace is 230-250 min, wherein the soaking time is more than or equal to 45 min.
Further, the rough rolling is carried out at the initial rolling temperature of 1100-1180 ℃ in a longitudinal-transverse-longitudinal rolling mode.
Further, the cooling controls the temperature of the steel plate to be 960-1060 ℃ and the finish rolling is started.
Furthermore, the finish rolling temperature is controlled to be 900-960 ℃, the thin specification is controlled according to the upper limit, and the thick specification is controlled by the lower limit.
Furthermore, the quenching temperature is controlled to be 770-830 ℃, the thin specification is controlled by an upper limit, and the thick specification is controlled by a lower limit.
Further, the tempering temperature is 690 ℃ -700 ℃, and the tempering time is the thickness of the steel plate +50 min.
The invention also provides a low-cost Q690 steel plate, and the low-cost Q690 steel plate has the chemical component content ratio of C: 0.12-0.18%, Si is less than or equal to 0.45%, Mn: 1.45-1.60%, P is less than or equal to 0.020%, S is less than or equal to 0.010%, Alt: 0.02 to 0.040%, Nb: 0.045-0.06%, Ti: 0.015-0.025%, B: 0.0025-0.0040%, N: 0.0040-0.0065 percent of carbon equivalent CEV, less than or equal to 0.44 percent of carbon equivalent CEV, and the balance of Cu, Ni and As, less than or equal to 0.80 percent and 0.080 percent.
Further, the thickness of the low-cost Q690 steel plate is 6-50 mm.
The principle of the invention is as follows: (1) cheap alloy elements are adopted to replace expensive elements to improve hardenability and austenite recrystallization temperature; (2) during rolling, high-temperature finish rolling is adopted, and the temperature is controlled after rolling so as to meet the temperature requirement during on-line quenching, so that the off-line heating quenching process is reduced; (3) and the production of the Q690 steel plate with the thickness of 6-50 mm is realized by adopting a reasonable heat treatment process. The measures comprise undetermined component design, production line arrangement, reasonable steel rolling process and heat treatment process.
Based on the principle, the invention discloses a low-cost Q690 steel plate and a production method thereof, and the specific measures comprise the following steps:
1. designing specific components: the low-cost B element is used for replacing expensive Ni, Cr and Mo, so that the hardenability is improved, and the steel plate can be completely quenched after being rolled to form a uniform martensite structure; the content of C is designed to be in the middle and upper limits of the standard, and A is reduced 3 The temperature reduces the quenching temperature requirement of the rolled steel plate, promotes the formation of martensite structure, and can change low-carbon-content high-purity alloy (metal manganese, low-carbon manganese, ferrosilicon and the like) which must be added during low-C design into low-cost silicomanganese alloy, thereby reducing the cost; adding microalloy elements such as Nb and Ti to increase the austenite recrystallization temperature, so that the billet is still in an austenite recrystallization region when finish rolling is carried out at a higher temperature, Ti can fix N in the steel to form nitrides, the strength is improved, the formation of nitrides between N and B is avoided, and the hardenability improvement effect of B is reduced, as shown in tables 1 and 2.
TABLE 1 chemical composition of low-cost Q690 steel plate (content percentage:%)
Figure BDA0003751272090000031
TABLE 2 Low cost Q690 Steel plate specification
Figure BDA0003751272090000032
(1) C content: the control is controlled at the middle and upper limit of the standard, and C element influences A of the steel 3 Temperature, increase in C content A 3 The temperature is reduced, and the quenching needs to be at A 3 Is carried out at a temperature higher than the temperature; therefore, the higher C content can ensure that the steel plate is quenched in a wider temperature range after being rolled, the process window area before quenching is enlarged, and the control difficulty is reduced.
(2) Si and Mn: the increase of Si content is favorable for strength but unfavorable for plasticity, so that the Si content should be controlled in a lower range; mn can improve the strength, plasticity and hardenability of the steel and should be controlled in a higher range.
(3) P, S are all harmful elements and should be controlled at a low level.
(4) Alt is a strong deoxidizing element, can refine grains and improve plasticity, and should be controlled within a certain range.
(5) Nb can increase the austenite recrystallization temperature, so that the steel billet is still in an austenite recrystallization region when finish rolling is carried out at a higher temperature, the temperature of the steel plate after rolling is increased, and the steel plate is still in the austenite region when quenching is carried out after rolling. Nb has precipitation strengthening effect, and can refine crystal grains and improve strength and plasticity.
(6) Ti, N, B: ti element raises austenite recrystallization temperature, so that the steel billet is still in an austenite recrystallization region when finish rolling is carried out at higher temperature, and Ti can fix N in steel to form nitride, thereby improving strength and welding performance; if the content of N is too low and the content of Ti matched with the N is too high, coarse TiN is formed to be unfavorable to plasticity, if the content of N is too high and the content of Ti matched with the N is too low, solid solution N is increased to be unfavorable to plasticity, and the improvement of hardenability brought by B is reduced, so that the content of N is matched with the content of Ti; the element B can improve the hardenability, the solid solution N is reduced after the Ti is added, the hardenability effect that the N and the B form nitride to reduce the B can be avoided, and the thicker the rolling specification, the higher the content of the B is.
(7) Ni, Cr, Mo, V: ni, Cr and Mo can improve hardenability and plasticity, but are expensive and are not added during production; the V element has strong precipitation strengthening effect and weak fine-grain strengthening effect, and the excessive precipitation strengthening causes the V element to be unfavorable to plasticity and expensive, so the V element is not added.
(8) Production organization: q690 can be produced in one tundish with Q345 and Q355 in steelmaking production, and the mixed pouring part of two steel grades can be judged as Q345 or Q355, so that the loss of mixed pouring is reduced, and the production cost is reduced.
2. Production line arrangement and production process
Heating furnace heating → high-pressure water descaling → roughing mill group → cooling device → finishing mill group → pre-straightening machine → electromagnetic induction heating → rapid cooling device (quenching) → hot straightening → cooling bed → tempering heat treatment.
The electromagnetic induction heating can adopt the existing slab induction heating device, when thin specifications (for example, 6mm-10mm) are produced, the surface temperature of the steel plate is quickly reduced after the finishing mill group is finished, the temperature before quenching is lower than the Ar3 temperature, and the steel plate enters a two-phase region to generate a ferrite structure. Therefore, an electromagnetic induction heating device is arranged behind the pre-straightening machine, the steel plate is heated by the skin effect of electromagnetic induction, so that the steel plate is in an austenite region and can be uniformly heated, and the temperature after heating is controlled to be 790-830 ℃.
Conventionally, there is no heating or temperature raising step after finish rolling and before quenching. Therefore, the steel plate can not be ensured to be in the austenitic low body region during the production of thin steel plates, and the thin steel plates are generally subjected to an off-line heating and then quenching process.
The induction heating device is introduced into a steel rolling production line, and the off-line heating before quenching is changed into on-line real-time heating, so that the interruption of a steel rolling process is avoided, and the production can be continuously carried out in real time.
The induction heating device is introduced into a steel rolling production line, the corresponding process is improved, for example, a multipoint temperature measuring device needs to be arranged in front of the induction heating device, temperature measuring data are transmitted into a computer to form a temperature curve, and when a steel plate reaches the induction heating device, the power of the induction heating device is dynamically adjusted by the computer according to the temperature curve, so that the surface temperature of the steel plate is ensured to be 790-830 ℃, and meanwhile, excessive waste is avoided.
A cooling device is arranged between the roughing mill group and the finishing mill group: after the roughly rolled austenite is recrystallized and rolled, the steel plate is still in an austenite recrystallization region, austenite grains can grow up again to influence the plasticity, at the moment, the cooling device is used for cooling the temperature of the steel plate to the austenite recrystallization region immediately, the growth of austenite grains can be controlled, the strength and the plasticity of a steel plate finished product are improved, and the production efficiency is improved.
3. Reasonable steel rolling process
(1) The heating requirement is as follows: the heating time is 230-250 min, wherein the soaking time is more than or equal to 45 min.
(2) The initial rolling temperature of rough rolling is 1100-1180 ℃, and the same-plate difference of water-cooling black marks is eliminated by adopting a longitudinal-transverse-longitudinal rolling mode.
(3) Two-stage rolling is adopted, in the rough rolling stage, the single-pass reduction rate is increased, and the final reduction rate of 2-3 passes is more than 20%; in the finish rolling stage, the single-pass reduction rate is increased, and the pass reduction rate is more than 10%.
(4) High-temperature finish rolling: immediately after rough rolling is finished, controlling a cooling device behind the rough rolling to control the temperature of the steel plate to be 960-1060 ℃ and starting finish rolling, controlling the finish rolling temperature of the finish rolling to be 900-960 ℃, controlling the heat dissipation speed of the steel plate to be high when the steel plate is rolled to be in a thin specification and controlling the temperature to be at an upper limit, controlling the heat dissipation speed of the steel plate to be low when the steel plate is rolled to be in a thick specification and controlling the temperature to be at a lower limit; the thicker the rolled gauge, the lower the temperature.
4. Post-rolling heat treatment
(1) Quenching temperature (cooling temperature): the temperature is controlled to be 770-830 ℃, the thin specification is controlled according to the upper limit, and the thick specification is controlled according to the lower limit. And (3) taking the steel plate out of the finishing mill group, measuring the surface temperature of the steel plate through the pre-straightening machine, forming a temperature curve, starting the electromagnetic induction heating device to heat when the temperature is lower than the set temperature, adjusting the heating power according to the surface temperature curve of the steel plate, and homogenizing the surface temperature. The surface temperature (re-reddening temperature) of the steel sheet after cooling should be less than 100 ℃.
(2) Tempering: tempering temperature is 690-700 ℃, and tempering time is as follows: the thickness of the steel plate is +50 min.
(3) And (3) metallographic requirements after tempering are as follows: the tempered sorbite proportion of the surface structure is more than 85 percent, the 1/4 part and the central part structure are tempered sorbite, and ferrite structure cannot occur.
The invention has the beneficial effects that: the invention avoids the addition of noble alloy elements such as Ni, Cr, Mo, V and the like, Q690 can be produced in one middle package as Q345, Q355 and the like during steelmaking production, and the mixed pouring part of two steel grades can be directly judged as Q345 or Q355, thereby improving the production efficiency and reducing the cost; the invention utilizes the waste heat of the finish-rolled steel plate to directly quench, reduces the heating procedure of off-line heating quenching, and has low energy consumption and high production efficiency.
Detailed Description
The present invention will now be described in order to more clearly understand the technical features, objects, and effects of the present invention.
1. The invention firstly carries out reasonable component design: the low-cost B element is used to replace expensive Ni, Cr and Mo to improve hardenability, the C content is designed to be in the standard middle and upper limits, and A is reduced 3 The temperature reduces the quenching temperature requirement of the rolled steel plate, meanwhile, the low-cost silicomanganese alloy replaces high-purity alloy (metal manganese, low-carbon manganese, ferrosilicon and the like) with low carbon content, the cost is reduced, microalloy elements such as Nb and Ti are added to improve the austenite recrystallization temperature, the Ti can fix N in the steel to form nitride, the strength is improved, the N and B are prevented from forming nitride, and the hardenability improvement effect of B is reduced. Table 3 shows the chemical composition (in percentage by weight) of the steel sheets according to the examples of the present invention. As shown in table 3, the composition of the present invention was controlled as follows:
TABLE 3 Steel plate chemical composition (%)
Examples of the invention C Si Mn P S Alt Nb Ti N B
Example 1 0.15 0.32 1.50 0.019 0.004 0.032 0.048 0.017 0.0050 0.0027
Example 2 0.17 0.35 1.51 0.016 0.003 0.028 0.050 0.020 0.0060 0.0025
Example 3 0.12 0.38 1.46 0.020 0.005 0.030 0.051 0.022 0.0065 0.0026
Example 4 0.18 0.42 1.45 0.015 0.003 0.031 0.049 0.018 0.0050 0.0030
Example 5 0.17 0.29 1.48 0.016 0.002 0.029 0.053 0.021 0.0062 0.0041
2. Specific process parameters for producing the Q690 steel plate with the thickness of 6-50 mm are detailed in Table 4.
Table 4: specific process parameters of the examples
Figure BDA0003751272090000061
Figure BDA0003751272090000071
3. In the embodiment of the invention, the metallographic structure is tempered sorbite, the yield strength of the steel plate is 740-820 Mpa, the tensile strength is 800-870 Mpa, the elongation after fracture is 12-20%, the average impact value is 100-160J, and the detailed mechanical properties are shown in Table 5.
Table 5: specific mechanical Properties after Heat treatment of the examples
Figure BDA0003751272090000072

Claims (10)

1. The production method of the low-cost Q690 steel plate is characterized in that the low-cost Q690 steel plate has the chemical component content ratio of C: 0.12-0.18%, Si is less than or equal to 0.45%, Mn: 1.45-1.60%, P is less than or equal to 0.020%, S is less than or equal to 0.010%, Alt: 0.02 to 0.040%, Nb: 0.045-0.06%, Ti: 0.015-0.025%, B: 0.0025-0.0040%, N: 0.0040 to 0.0065 percent of carbon equivalent CEV which is less than or equal to 0.44 percent, and the balance of Cu which is less than or equal to 0.80 percent, Ni which is less than or equal to 0.80 percent and As which is less than or equal to 0.080 percent;
the production method of the low-cost Q690 steel plate comprises the following process steps of sequentially carrying out:
heating by a heating furnace, removing phosphorus by high-pressure water, rough rolling, cooling, finish rolling, straightening by a pre-straightening machine, electromagnetic induction heating, quenching, hot straightening, cooling bed and tempering heat treatment.
In the rough rolling stage, the single-pass reduction rate is increased, and the final reduction rate of 2-3 passes is more than 20%; and in the finish rolling stage, increasing the single-pass reduction rate, wherein the pass reduction rate is more than 10%, discharging the steel plate out of a finish rolling unit, measuring the surface temperature of the steel plate through a pre-straightening machine to form a temperature curve, adjusting the heating power according to the surface temperature curve of the steel plate, and controlling the surface temperature to be uniform.
2. The method for producing the low-cost Q690 steel plate as claimed in claim 1, wherein the thickness of the steel plate is 6-50 mm.
3. The method for producing the low-cost Q690 steel plate as claimed in claim 1, wherein the heating time of the heating furnace is 230-250 min, wherein the soaking time is more than or equal to 45 min.
4. The method for producing the low-cost Q690 steel plate as claimed in claim 1, wherein the rough rolling is performed at a controlled start rolling temperature of 1100-1180 ℃ by a longitudinal-transverse-longitudinal rolling mode.
5. The method of claim 1, wherein the cooling controls the temperature of the steel sheet to 960-1060 ℃ to start the finish rolling.
6. The method for producing the low-cost Q690 steel plate as claimed in claim 1, wherein the finish rolling temperature is controlled to 900 to 960 ℃, the thin gauge is controlled to an upper limit, and the thick gauge is controlled to a lower limit.
7. The method for producing the low-cost Q690 steel plate as claimed in claim 1, wherein the quenching temperature is controlled to 770-830 ℃, the thin gauge is controlled by an upper limit, and the thick gauge is controlled by a lower limit.
8. The method for producing the low-cost Q690 steel plate as claimed in claim 1, wherein the tempering temperature is 690-700 ℃ and the tempering time is +50 min.
9. A low-cost Q690 steel plate, characterized in that the low-cost Q690 steel plate has a chemical component content ratio of C: 0.12-0.18%, Si is less than or equal to 0.45%, Mn: 1.45-1.60%, P is less than or equal to 0.020%, S is less than or equal to 0.010%, Alt: 0.02 to 0.040%, Nb: 0.045-0.06%, Ti: 0.015-0.025%, B: 0.0025-0.0040%, N: 0.0040 to 0.0065 percent of carbon equivalent CEV which is less than or equal to 0.44 percent, and the balance of Cu which is less than or equal to 0.80 percent, Ni which is less than or equal to 0.80 percent and As which is less than or equal to 0.080 percent; the low-cost Q690 steel plate is produced by the method for producing the low-cost Q690 steel plate according to any one of claims 1 to 8.
10. The low-cost Q690 steel sheet of claim 9, wherein the thickness of said steel sheet is 6-50 mm.
CN202210843516.7A 2022-07-18 2022-07-18 Low-cost Q690 steel plate and production method thereof Pending CN115094331A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210843516.7A CN115094331A (en) 2022-07-18 2022-07-18 Low-cost Q690 steel plate and production method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210843516.7A CN115094331A (en) 2022-07-18 2022-07-18 Low-cost Q690 steel plate and production method thereof

Publications (1)

Publication Number Publication Date
CN115094331A true CN115094331A (en) 2022-09-23

Family

ID=83299266

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210843516.7A Pending CN115094331A (en) 2022-07-18 2022-07-18 Low-cost Q690 steel plate and production method thereof

Country Status (1)

Country Link
CN (1) CN115094331A (en)

Citations (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030056859A1 (en) * 2001-07-17 2003-03-27 Nissan Motor Co., Ltd. Case hardening steel and carburized part using same
CN102286691A (en) * 2011-09-07 2011-12-21 柳州钢铁股份有限公司 Steel plate for automobile axle housing and production method thereof
CN104264064A (en) * 2014-09-15 2015-01-07 江阴兴澄特种钢铁有限公司 Extra-thick-gauge Q690 high-strength Structural steel plate and preparation method of structural steel plate
CN106011626A (en) * 2016-07-04 2016-10-12 湖南华菱湘潭钢铁有限公司 Production method for hydrogenation medium-thickness steel plate
CN106319350A (en) * 2016-11-30 2017-01-11 湖南华菱涟源钢铁有限公司 Rolling and heat treatment production method of high-strength steel 900MPa-grade in yield strength
CN106435379A (en) * 2016-10-17 2017-02-22 江阴兴澄特种钢铁有限公司 550 MPa level extra-thick easy-welding high-toughness layered-tearing-resisting steel plate and manufacturing method thereof
CN106756542A (en) * 2016-12-09 2017-05-31 南京钢铁股份有限公司 A kind of low cost production thereof of high-strength shipbuilding section
CN106756618A (en) * 2016-11-26 2017-05-31 江阴兴澄特种钢铁有限公司 100mm thickness Q420GJCD controlled rolling state high-strength structure steel plates
US20180298463A1 (en) * 2016-04-19 2018-10-18 Jiangyin Xingcheng Special Steel Works Co., Ltd Pressure vessel steel plate resistant against hydrogen-induced cracking and manufacturing method thereof
CN109252107A (en) * 2018-11-30 2019-01-22 湖南华菱湘潭钢铁有限公司 A kind of production method of high straightness super-high strength steel
CN110423946A (en) * 2019-09-02 2019-11-08 湖南华菱湘潭钢铁有限公司 A kind of production method of low compression ratio super-high strength steel Q960E special heavy plate
CN110468326A (en) * 2019-08-01 2019-11-19 江阴兴澄特种钢铁有限公司 A kind of LNG storage tank ultra-thin specification 16MnDR steel plate and its manufacturing method
CN110699599A (en) * 2019-09-25 2020-01-17 南京钢铁股份有限公司 Q345R steel for ultralow temperature and manufacturing method thereof
US20200071783A1 (en) * 2016-10-18 2020-03-05 Jiangyin Xing Cheng Special Steel Works Co., Ltd A rack steel plate with a thickness up to 177.8 mm by a continuous casting slab and manufacturing method thereof
CN111172465A (en) * 2020-02-28 2020-05-19 鞍钢股份有限公司 Low-carbon equivalent large-thickness Q390GJ steel plate for building structure and manufacturing method thereof
CN111926234A (en) * 2020-08-12 2020-11-13 宝武集团鄂城钢铁有限公司 Production method for producing super-thick high-strength steel plate for building with excellent thickness directivity based on continuous casting billet single frame
WO2021017520A1 (en) * 2019-07-31 2021-02-04 江阴兴澄特种钢铁有限公司 Wear-resistant steel with excellent surface quality and preparation method therefor
CN112921241A (en) * 2021-01-25 2021-06-08 广西柳钢华创科技研发有限公司 Production method of Q460 grade building steel with low yield ratio and high toughness under air cooling
WO2021179443A1 (en) * 2020-03-11 2021-09-16 江阴兴澄特种钢铁有限公司 Ultra-thick container steel plate with good low-temperature impact toughness in core and manufacturing method therefor
WO2021196821A1 (en) * 2020-03-30 2021-10-07 江阴兴澄特种钢铁有限公司 Method for preparing 80-100 mm extra-thick eh36 steel for offshore wind power
WO2021208178A1 (en) * 2020-04-17 2021-10-21 南京钢铁股份有限公司 690 mpa-graded easy-to-weld corrosion-resisting high-strength steel and manufacturing method therefor
CN113528966A (en) * 2021-07-19 2021-10-22 新疆八一钢铁股份有限公司 Production method of steel plate with thickness of 50-80mm for building structure
CN113846266A (en) * 2021-09-16 2021-12-28 湖南华菱湘潭钢铁有限公司 Production method of high-ductility and toughness quenched and tempered steel plate with yield strength of 1300MPa
WO2022011935A1 (en) * 2020-07-17 2022-01-20 南京钢铁股份有限公司 High-strength container thick plate having excellent core toughness, and manufacturing method
WO2022011936A1 (en) * 2020-07-17 2022-01-20 南京钢铁股份有限公司 High-strength vessel plate having excellent low-temperature toughness and manufacturing method
WO2022022047A1 (en) * 2020-07-30 2022-02-03 江阴兴澄特种钢铁有限公司 Low-yield-ratio granular bainite high-strength steel plate used in low-temperature environment and manufacturing method therefor
WO2022033128A1 (en) * 2020-08-14 2022-02-17 江阴兴澄特种钢铁有限公司 Normalized-condition delivered 100-120mm thick fh36 steel plate for offshore wind power pipe piles and preparation method therefor
CN114369753A (en) * 2022-01-07 2022-04-19 鞍钢股份有限公司 Method for producing multi-strength-level alloy structural steel based on flexible rolling technology
CN114540580A (en) * 2022-03-11 2022-05-27 新疆八一钢铁股份有限公司 Production method of low-cost Q345Q series bridge steel plate
CN114645191A (en) * 2022-02-11 2022-06-21 柳州钢铁股份有限公司 Low-cost high-toughness high-weldability high-strength ship board and preparation method thereof
CN114737130A (en) * 2022-04-29 2022-07-12 鞍钢股份有限公司 355 MPa-grade low-temperature steel and manufacturing method thereof

Patent Citations (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030056859A1 (en) * 2001-07-17 2003-03-27 Nissan Motor Co., Ltd. Case hardening steel and carburized part using same
CN102286691A (en) * 2011-09-07 2011-12-21 柳州钢铁股份有限公司 Steel plate for automobile axle housing and production method thereof
CN104264064A (en) * 2014-09-15 2015-01-07 江阴兴澄特种钢铁有限公司 Extra-thick-gauge Q690 high-strength Structural steel plate and preparation method of structural steel plate
US20180298463A1 (en) * 2016-04-19 2018-10-18 Jiangyin Xingcheng Special Steel Works Co., Ltd Pressure vessel steel plate resistant against hydrogen-induced cracking and manufacturing method thereof
CN106011626A (en) * 2016-07-04 2016-10-12 湖南华菱湘潭钢铁有限公司 Production method for hydrogenation medium-thickness steel plate
CN106435379A (en) * 2016-10-17 2017-02-22 江阴兴澄特种钢铁有限公司 550 MPa level extra-thick easy-welding high-toughness layered-tearing-resisting steel plate and manufacturing method thereof
US20200071783A1 (en) * 2016-10-18 2020-03-05 Jiangyin Xing Cheng Special Steel Works Co., Ltd A rack steel plate with a thickness up to 177.8 mm by a continuous casting slab and manufacturing method thereof
CN106756618A (en) * 2016-11-26 2017-05-31 江阴兴澄特种钢铁有限公司 100mm thickness Q420GJCD controlled rolling state high-strength structure steel plates
CN106319350A (en) * 2016-11-30 2017-01-11 湖南华菱涟源钢铁有限公司 Rolling and heat treatment production method of high-strength steel 900MPa-grade in yield strength
CN106756542A (en) * 2016-12-09 2017-05-31 南京钢铁股份有限公司 A kind of low cost production thereof of high-strength shipbuilding section
CN109252107A (en) * 2018-11-30 2019-01-22 湖南华菱湘潭钢铁有限公司 A kind of production method of high straightness super-high strength steel
WO2021017520A1 (en) * 2019-07-31 2021-02-04 江阴兴澄特种钢铁有限公司 Wear-resistant steel with excellent surface quality and preparation method therefor
CN110468326A (en) * 2019-08-01 2019-11-19 江阴兴澄特种钢铁有限公司 A kind of LNG storage tank ultra-thin specification 16MnDR steel plate and its manufacturing method
CN110423946A (en) * 2019-09-02 2019-11-08 湖南华菱湘潭钢铁有限公司 A kind of production method of low compression ratio super-high strength steel Q960E special heavy plate
CN110699599A (en) * 2019-09-25 2020-01-17 南京钢铁股份有限公司 Q345R steel for ultralow temperature and manufacturing method thereof
CN111172465A (en) * 2020-02-28 2020-05-19 鞍钢股份有限公司 Low-carbon equivalent large-thickness Q390GJ steel plate for building structure and manufacturing method thereof
WO2021179443A1 (en) * 2020-03-11 2021-09-16 江阴兴澄特种钢铁有限公司 Ultra-thick container steel plate with good low-temperature impact toughness in core and manufacturing method therefor
WO2021196821A1 (en) * 2020-03-30 2021-10-07 江阴兴澄特种钢铁有限公司 Method for preparing 80-100 mm extra-thick eh36 steel for offshore wind power
WO2021208178A1 (en) * 2020-04-17 2021-10-21 南京钢铁股份有限公司 690 mpa-graded easy-to-weld corrosion-resisting high-strength steel and manufacturing method therefor
WO2022011935A1 (en) * 2020-07-17 2022-01-20 南京钢铁股份有限公司 High-strength container thick plate having excellent core toughness, and manufacturing method
WO2022011936A1 (en) * 2020-07-17 2022-01-20 南京钢铁股份有限公司 High-strength vessel plate having excellent low-temperature toughness and manufacturing method
WO2022022047A1 (en) * 2020-07-30 2022-02-03 江阴兴澄特种钢铁有限公司 Low-yield-ratio granular bainite high-strength steel plate used in low-temperature environment and manufacturing method therefor
CN111926234A (en) * 2020-08-12 2020-11-13 宝武集团鄂城钢铁有限公司 Production method for producing super-thick high-strength steel plate for building with excellent thickness directivity based on continuous casting billet single frame
WO2022033128A1 (en) * 2020-08-14 2022-02-17 江阴兴澄特种钢铁有限公司 Normalized-condition delivered 100-120mm thick fh36 steel plate for offshore wind power pipe piles and preparation method therefor
CN112921241A (en) * 2021-01-25 2021-06-08 广西柳钢华创科技研发有限公司 Production method of Q460 grade building steel with low yield ratio and high toughness under air cooling
CN113528966A (en) * 2021-07-19 2021-10-22 新疆八一钢铁股份有限公司 Production method of steel plate with thickness of 50-80mm for building structure
CN113846266A (en) * 2021-09-16 2021-12-28 湖南华菱湘潭钢铁有限公司 Production method of high-ductility and toughness quenched and tempered steel plate with yield strength of 1300MPa
CN114369753A (en) * 2022-01-07 2022-04-19 鞍钢股份有限公司 Method for producing multi-strength-level alloy structural steel based on flexible rolling technology
CN114645191A (en) * 2022-02-11 2022-06-21 柳州钢铁股份有限公司 Low-cost high-toughness high-weldability high-strength ship board and preparation method thereof
CN114540580A (en) * 2022-03-11 2022-05-27 新疆八一钢铁股份有限公司 Production method of low-cost Q345Q series bridge steel plate
CN114737130A (en) * 2022-04-29 2022-07-12 鞍钢股份有限公司 355 MPa-grade low-temperature steel and manufacturing method thereof

Similar Documents

Publication Publication Date Title
CN106319378B (en) A kind of thin steel for saw blade substrate of major diameter and its manufacture method
CN110184525B (en) High-strength Q500GJE quenched and tempered steel plate for building structure and manufacturing method thereof
CN105088089B (en) Automobile cold-rolled selector fork steel beam column and production method
CN106319368A (en) Economical thin chain plate and manufacturing method thereof
CN111424219B (en) Method for manufacturing gear shaft steel capable of being directly subjected to cold forging
CN109112433B (en) Without 590MPa grades of cold-rolled biphase steels of striated surface defect and production method
CN105177422B (en) Ultra-long thin EH36 steel and production method of ultra-long thin EH36 steel on steckle mill
CN105401090B (en) A kind of precision stamping automotive seat regulation tooth plate cold-rolled steel sheet and its manufacture method
CN109252107B (en) Production method of high-flatness ultrahigh-strength steel
CN103451520A (en) Q345 engineering steel and production method thereof
CN107012398A (en) A kind of Nb-microalloying TRIP steel and preparation method thereof
CN111763883A (en) Steel for hollow stabilizer bar and production method thereof
CN109234612B (en) High-toughness B-containing hot-rolled low-carbon bainite steel plate and production method thereof
CN111647806B (en) Rolling process of Ti-containing low alloy steel
CN105274431A (en) Hot-rolling strip-steel harrow disk suitable for water quenching and manufacture method thereof
CN109609729A (en) A kind of yield strength 650MPa grades of stainless steel plates and manufacturing method
CN112501501A (en) TMCP (thermal mechanical control processing) on-line quenching high-strength wear-resistant steel NM450 coiled plate and production method thereof
CN106319376B (en) A kind of novel low welding crack sensibility high-strength steel plate
CN110938771A (en) Hot-rolled steel plate for wheel with tensile strength of 630MPa and manufacturing method thereof
CN111621716B (en) Nb-containing low alloy steel rolling process
CN105543680B (en) Micro- boron processing tensile strength 700MPa levels Wide and Thick Slab and manufacture method
CN113846266A (en) Production method of high-ductility and toughness quenched and tempered steel plate with yield strength of 1300MPa
CN112779401B (en) High-reaming hot-rolled pickled steel plate with yield strength of 550MPa
CN109988968B (en) Low-carbon equivalent large-thickness Q690E-grade high-strength steel plate and production method thereof
CN115094331A (en) Low-cost Q690 steel plate and production 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