CN111926253B - Hydrogen sulfide corrosion resistant high-strength toughness normalized steel and manufacturing method thereof - Google Patents
Hydrogen sulfide corrosion resistant high-strength toughness normalized steel and manufacturing method thereof Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- C—CHEMISTRY; METALLURGY
- 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
- C21D1/26—Methods of annealing
- C21D1/28—Normalising
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
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- C—CHEMISTRY; METALLURGY
- 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
- C21D2211/001—Austenite
Abstract
The invention discloses a normalized steel with hydrogen sulfide corrosion resistance and high strength and toughness, which comprises the following components: c: 0.08-0.11%; si: 0.25 to 0.40 percent; mn: 1.30-1.40%; cr: 0.20-0.30%; nb: 0.030-0.045%; ti: 0.010-0.020%; and (3) Alt: 0.020-0.040%; p: less than or equal to 0.012 percent; s: less than or equal to 0.0020 percent; n: less than or equal to 0.0045 percent; h: less than or equal to 0.0002 percent; ca: 0.0025-0.0040%. The invention also discloses a manufacturing method of the steel plate, which comprises the steps of molten iron pretreatment, converter smelting, LF furnace refining, RH vacuum treatment, continuous casting billet casting, continuous casting billet heating and rolling and normalizing heat treatment. The steel material has stable comprehensive mechanical property and meets the requirement of H resistance2S corrosion requirements and also meets the requirements of low-crack sensitivity steel.
Description
Technical Field
The invention belongs to the technical field of metal material manufacturing, and particularly relates to normalized steel with hydrogen sulfide corrosion resistance and high strength and toughness and a manufacturing method thereof, in particular to normalized steel with high strength, high toughness and a normalized state and moisture-proof hydrogen sulfide (H)2S) corrosion-resistant steel, namely low-alloy structural steel with yield strength of more than or equal to 355MPa, tensile strength of more than or equal to 510MPa grade, transverse impact energy of more than or equal to 100J at-60 ℃, and excellent Hydrogen Induced Cracking (HIC) and sulfide stress corrosion cracking (SSC) resistance under the normalizing condition.
Background
With the trend of deterioration of resource quality, large-scale equipment and light-weight equipment, high-strength and high-toughness steel grades need to be selected in design. Combines different new technologies and new processes of refining, continuous casting, die casting, electroslag remelting, controlled rolling and the like, adopts a microalloying technology, controls lower inclusion content and low S, low H and uniform and fine grain structure, can ensure steel grades with higher strength grade, and has good H resistance2S corrosion performance.
Since the middle of the 90 s of the 20 th century, petrochemical enterprises have gradually progressedThe proportion of high-S-content crude oil in the middle east of refining is increased, the acid value and the S content of domestic crude oil are gradually increased, and the problem of low-temperature corrosion of sulfide is more and more prominent. Wet H2The corrosion of pressure vessels and pipelines, HIC, SSC and other accidents caused under the S environment are in a continuously rising trend, and the safe operation of production devices of petrochemical enterprises is seriously disturbed. Wet H2The loss caused by the destruction of equipment caused by S environment is huge, and is one of the most prominent corrosion problems and technical problems in the current oil extraction, oil refining, chemical industry and gas production. Meanwhile, the wet H tends to decrease in wall thickness with the increase in size and weight of the apparatus2The demand of the steel plate for the S environment is increased year by year, and the steel plate is mainly used for petroleum and petrochemical enterprises and natural gas extraction enterprises for extracting, transporting, storing and pretreating crude oil and natural gas. Hydrogen induced cracking of steel is usually initiated without significant warning, resulting in sudden cracking of the container, which is extremely destructive. Therefore, the steel sheet for oil and gas storage containers is required to have not only excellent properties such as sufficient strength, hardness, impact toughness, low-temperature fracture toughness, good welding properties and workability, but also good acid resistance, i.e., sufficient HIC resistance and SSC resistance.
The selection of engineering equipment materials firstly determines corresponding performance requirements according to application range, stress condition, failure mode, service environment and the like, gives full play to potential performance of material selection, and reasonably utilizes steel. In recent years, with the development of large-scale boiler and pressure vessel products and the increasingly harsh application environment, the demand and demand for steel plates have been increasing and increasing. The development of pressure vessel steels having good toughness, acid resistance, and corrosion resistance has become increasingly urgent. At present, high-grade and large-thickness steel plates are the main research and development directions of steel for oil and gas transportation and storage in China for safe, efficient and economic transportation and oil and gas resource storage.
In the prior art 1, the Chinese patent with the application number of CN 107034414A, namely the high-strength normalizing container steel with the yield strength of 415MPa and the heat treatment method thereof, different normalizing heating temperatures and different normalizing heating methods are adopted on the premise of designing high V (0.10-0.18%) and high Ni (0.40-0.70%) componentsThe corresponding heating time is adopted to obtain the high-strength container steel with the yield strength of more than or equal to 415MPa, the tensile strength of 550-. The addition of excessive V, Ni alloy elements greatly increases the alloy cost; meanwhile, the patent has loose P, S requirements, and the requirement is satisfied with 0.035%. Under the design condition of the components, the strength grade can reach 415MPa grade through normalizing treatment, but the impact toughness of the steel has a problem; meanwhile, the toughness index is not reflected in the embodiment, and the patent cannot meet the requirements of the high-strength high-toughness normalized steel; this patent does not mention anti-H2S corrosion performance index.
Prior art 2, Chinese patent invention with application number "CN 104694836A", an acid-resistant steel plate for steel structure engineering, comprises "high C (0.27-0.29%), low Mn (0.35-0.37%), low P (0.006-0.008%)," high C (0.27-0.29%), low Mn (0.35-0.37%), and,
The steel plate with good obdurability and acid resistance is obtained by the component design of low S (0.002-0.005%), Nb (0.03-0.05%), V (0.04-0.06%), high Ti (0.15-0.17%), high Ni (1.65-1.67%), high Cr (0.54-0.56%) and Mo (0.13-0.15%), and by adopting the heat treatment process of 'primary normalizing, secondary normalizing and tempering'. After normalizing or tempering, a complex cross cooling process is adopted, such as air cooling, compressed air or mist quenching liquid and air cooling and the like, and the temperature is cooled to the room temperature from the normalizing or tempering temperature in a sectional manner. Through strict limitation of components and a heat treatment process, reasonable two-phase ratio, fine ferrite and pearlite in dispersed distribution are obtained, and the formation of a banded structure is avoided. The comprehensive mechanical properties of the steel plate in the embodiment comprise: yield strength of 314-
39.5 percent, the reduction of area is 60.5-70.0 percent, and the impact energy at minus 20 ℃ is 230-. The patent adopts a higher alloy design, and the production cost is inevitably higher. In addition, the heat treatment process is too complex, and the heat treatment process is generally difficult to popularize and apply in industrial production. In addition, despite their good HIC and SSC resistance, the strength grades are low, with toughness indexes of only-20 ℃. By adopting the high component design and the complex process requirement, only the steel with lower obdurability for steel structure engineering is obtained, which is not in the way of the development trend of resource-saving and environment-friendly green steel.
Prior art 3, Chinese patent of invention with application number "CN 102392185A", a normalized acid-resistant hot rolled steel sheet and a manufacturing method thereof, the component design comprises: c (0.061-0.151%), Si (0.10-0.45%), Mn (0.50-0.99%), P (less than or equal to 0.009%), S (less than or equal to 0.0015%), Alt (0.02-0.06%), V (0.045)
-0.085%), Ti (0.005-0.040%), Cr (0.05-0.35%), Mo (0.00-0.15%). Through the process of rolling control and normalizing, the yield strength is 440MPa in 300-. The alloy cost is high by adding alloy elements such as Cr, Mo, V and the like; in the refining process, only LF is adopted, and RH or VD vacuum treatment is lacked, so that the purity of the molten steel is difficult to ensure; the impact temperature is only 0 ℃, and the requirement of high toughness cannot be met. In general, the patent adopts normal metallurgical procedures to obtain the conventional acid-resistant product with performance and quality and no obvious characteristics or advantages.
Prior art 4, chinese patent application No. CN 105603304 a, a thick steel plate for Q370R pressure vessel with good HIC and SSCC resistance and a manufacturing method thereof; the component design is as follows: c: 0.12-
0.17％、Si:0.15-0.40％、Mn:1.40-1.65％、Cu:0.10-0.30％、Mo:0.05-0.08％、Nb:0.015-
0.040 percent, 0.015 to 0.050 percent of V, less than or equal to 0.012 percent of P and less than or equal to 0.002 percent of S; the pressure vessel with the specification of 10-60mm is produced by adopting a normalizing and water cooling process, and the water cooling speed is 5-40 ℃/s after the normalizing is finished. In the structure within 20% of the total thickness of the upper and lower surfaces of the steel sheet, the proportion of acicular ferrite and bainite is more than 50%, and no obvious banded structure exists. The addition of Cu, Mo and V alloy leads to high alloy cost. The unconventional normalizing process, namely accelerated cooling by water cooling after normalizing, has poor tissue uniformity. The steel plate has large structural difference in the thickness direction, easily generates structural stress, and has adverse effect on acid resistance. In addition, the thick steel plate produced by the normalizing and water cooling process has larger performance difference at different positions in the thickness direction, is not a normal and pure normalizing heat treatment process, and does not meet the definition and standard of normalizing.
In prior art 5, a high-toughness a516Gr60 sheet for an acid environment pipeline, which is a chinese patent with application number "CN 109811261 a", and a production method thereof, adopt "C: 0.15-0.20%, Si: 0.20-0.40%, Mn: 0.70-1.20%, P is less than or equal to 0.008%, S is less than or equal to 0.002%, Al: 0.020 to 0.040%, Nb: 0.010-0.015%, Mo: 0.05-0.12%, Ca: 0.0015-0.0030 percent, and less than or equal to 0.003 percent, and the process of rolling control and normalizing can produce the A516 Gr.60 sheet with the specification of 8-30mm for the acid environment pipeline with the yield strength of 315 plus 360MPa, the tensile strength of 430 plus 500MPa and the transverse impact energy of-50 ℃ of more than or equal to 100J. In the smelting process, the superheat degree of the molten steel is 10-20 ℃, and the throwing speed is 0.80-1.00 min/mm. In the controlled rolling process, the maximum heating temperature of the continuous casting billet is 1190-1210 ℃, and the total heating time is more than or equal to 11 min/mm; the rolling of the first stage requires that the single-pass reduction rate is 10-30%, the cumulative reduction rate is 30-50%, the single-pass reduction rate of the rolling of the second stage is 10-30%, and the cumulative reduction rate is 30-50%. In the normalized acid-resistant steel, a certain amount of the alloy element Mo is added, so that the cost is increased, and meanwhile, the precipitation of Mo and the carbide thereof is not necessarily favorable for the anti-HIC performance, especially under the normalized condition. In the casting process of the continuous casting billet, the superheat degree is required to be less than or equal to 20 ℃, the production difficulty is high, and the condition of batch industrial application is not met. Meanwhile, the continuous casting billet withdrawal speed is required to be 0.80-1.00min/mm, and the withdrawal speed is low, so that the production efficiency is extremely low and is contrary to the high efficiency of a normal continuous casting machine. In addition, in the heating process of the continuous casting billet, the ultra-long in-furnace time tends to seriously coarsen austenite grains. In the rolling process, the maximum single-pass reduction rate of the first stage and the maximum single-pass reduction rate of the second stage are both required to be 30%, but the cumulative reduction rate does not exceed 50%, and the excessively high single-pass reduction rate cannot be realized in the actual production process, and simultaneously limits the cumulative reduction rate and is seriously inconsistent with the actual rolling condition. The rolling schedule design (single pass reduction and cumulative reduction) is not reasonable and cannot be achieved, particularly in the examples. In general, the patent does not meet the actual conditions from component design to process requirements, and cannot be realized in actual production, or even if the patent can be realized, the production cost is too high, the efficiency is low, and the conditions of batch industrial popularization and application are not met.
Normalized anti-H2The steel for S corrosion refers to an acid-resistant steel grade requiring C, Mn elements for strength improvement, which generally requires a normalizing heat treatment after rolling. In order to ensure the strength after heat treatment, C, Mn elements are added, and other alloy elements which are favorable for improving the strength and toughness are properly added. Production of moisture-resistant H under the current metallurgical conditions2S corrosion resistant steel, under TMCP process conditions, by optimizing components and rolling process, H resistance is obtained2S corrosion favourable microstructures, such as acicular ferrite, can be achieved substantially while the yield strength levels can reach 450MPa or higher, such as HIC/SSC resistant pipeline steels, which can already reach X80 levels. However, under pure fire conditions, the high strength and high toughness of the material are ensured and the H resistance is also ensured under the influence of the components, the structure and the performance2The corrosion performance of S is difficult, related reports or researches are rarely made, and no mature product is produced.
Disclosure of Invention
The invention aims to provide a normalized steel with high strength and toughness and hydrogen sulfide corrosion resistance and a manufacturing method thereof, wherein the normalized steel has H resistance through reasonable design2The component system of S corrosion normalized steel is characterized by that on the basis of low C component system and on the premise of adding proper quantity of necessary low-cost alloy elements of Mn and Cr and micro-alloy elements of Nb and Ti, a two-stage controlled rolling, controlled cooling process and optimized normalizing heat treatment process are used to develop a normalized steel with high toughness and H-resistance whose tensile strength is greater than 510MPa grade2The S corrosion low alloy structural steel solves the problems of low strength grade, insufficient toughness and H resistance of the prior normalizing steel2And poor corrosion performance of S (HIC and SSC).
The invention is realized by the following technical scheme: the normalized steel with high strength and toughness and hydrogen sulfide corrosion resistance is characterized in that: comprises the following components in percentage by weight: c: 0.08-0.11%; si: 0.25 to 0.40 percent; mn: 1.30-1.40%; cr: 0.20-0.30%; nb: 0.030-0.045%; ti: 0.010-0.020%; and (3) Alt: 0.020-0.040%; p: less than or equal to 0.012 percent; s: less than or equal to 0.0020 percent; n: less than or equal to 0.0045 percent; h: less than or equal to 0.0002 percent; ca: 0.0025-0.0040%; the balance of Fe and inevitable impurities; wherein the carbon equivalent CEV is in the range of 0.34-0.39%, and the weld crack sensitivity index Pcm is in the range of 0.16-0.19%.
A manufacturing method of normalized steel with hydrogen sulfide corrosion resistance and high strength and toughness is characterized in that: the method comprises the following steps:
(1) a molten iron pretreatment step: adopting a deep desulfurization mode, adding 500kg of small-particle lime at the bottom of a ladle, setting the initial S content according to the actual value by 1.2 times, and setting the target S content to be less than or equal to 0.003%; the quantity of sprayed Mg is 10kg more than that of theoretical calculation, slag skimming operation is carried out after the spraying is finished, slag is skived for 4-5min, then 60-80kg of slag conglomeration agent is added, and the skimming is carried out for 3-4min after stopping for 2min, so that the net slag skimming time is guaranteed to be more than or equal to 7 min;
(2) a converter smelting step: the tapping temperature of the converter is 1650 +/-20 ℃; adopting a double-slag method, pulling C at low temperature to remove P, and then blowing to remove C, wherein the post-blowing rate is 100%; the blowing process adopts a bottom blowing argon mode, and the initial bottom blowing argon flow is 420 +/-10 m3Flow rate of bottom blowing argon 520 +/-10 m at the final stage of converting3H; when the steel is tapped at 1/3, lime and fluorite are added along with the steel flow for slag washing; after tapping, adding an aluminum grate on the slag surface;
(3) and (3) refining in an LF (ladle furnace): regulating Mn with low-carbon ferromanganese, wherein the LF finishing temperature is 1635 +/-10 ℃; controlling the Al content at the end of LF according to 0.020-0.050%, wherein the total aluminum adjusting amount of the LF is not more than 5 kg/ton of molten steel; adding ferrotitanium to adjust Ti before the LF is discharged, wherein the absorption rate is 80-85%; the content of P is between 0.005 and 0.006 percent; the content of S is between 0.0006 and 0.008 percent; the Ca content is between 25 and 40ppm, and the value of Ca/S is more than 1.25;
(4) RH vacuum treatment step: the RH processing ending temperature is 1585 +/-5 ℃, and the soft blowing ending temperature is 1565 +/-5 ℃; the argon flow is increased to 800-1200 NL/min, and the deep vacuum treatment time is guaranteed to be more than or equal to 15 min; after the final batch of alloy is adjusted, the vacuum treatment time is required to be more than or equal to 5 min; after the vacuum is finished, hydrogen determination is carried out; soft blowing is carried out on the molten steel before the ladle is hung, the flow of soft argon blowing is controlled to be less than or equal to 100L/min, the slag surface cannot be turned over, the soft blowing time of the molten steel is ensured to be more than or equal to 12min, and the molten steel calming time after the soft blowing is more than or equal to 5 min;
(5) and (3) casting a continuous casting blank: adopting a blank with the thickness of 300mm multiplied by 2000mm, the drawing speed is 0.75-0.85m/min, and the average superheat degree is less than or equal to 25 ℃; the reduction of the two-phase area and the solid phase area is increased under dynamic light pressure, the maximum reduction rate is 1.30mm/m, the maximum reduction of the two-phase area is 8mm, and the maximum reduction of the solid phase area is 1 mm;
(6) heating and rolling a continuous casting blank: a walking beam type heating furnace is adopted in the heating process, the heating soaking temperature is 1220-1260 ℃, and the in-furnace time is 280-360 min, so as to ensure the full austenitization of the continuous casting billet; in the rolling process, a controlled rolling control process is adopted, the rolling finishing temperature of the recrystallization zone is required to be 1000-1050 ℃, and the thickness to be heated is 2.0-4.5 times of the thickness of a finished steel plate. The total reduction rate of the rolling stage in the recrystallization zone is more than or equal to 60 percent, and in the longitudinal rolling process after widening, the single-pass reduction rate presents an increasing mode, and the single reduction of the last 2 passes of rolling in the recrystallization zone is required to be more than or equal to 35 mm. The rolling starting temperature of the non-recrystallization zone is 860-920 ℃, the rolling finishing temperature of the non-recrystallization zone is 800-840 ℃, and the total reduction rate of the rolling stage of the non-recrystallization zone is more than or equal to 50 percent; the single-pass reduction rate of all passes before the last 2 passes of rolling in the non-recrystallization region is more than or equal to 10 percent, the reduction of the last two passes is less than or equal to 5mm, after the steel plate is rolled, the steel plate quickly enters a cooling device for cooling, the water inlet temperature is 770-; rapidly performing off-line stack cooling after the steel plate is rolled, wherein the stack cooling temperature range is 400-500 ℃, and the stack cooling time range is 24-48 h;
(7) normalizing heat treatment: the normalizing temperature is 862-876 ℃; the total in-furnace time in the normalizing process = heating furnace coefficient x steel plate thickness + holding time.
Wherein: in the step (2), the addition amount of the lime is 2.5-2.8 kg/ton of molten steel, the addition amount of the fluorite is 0.05-0.06 kg/ton of molten steel, and the addition amount of the aluminum grate is 0.03-0.04 kg/ton of molten steel.
Wherein: in the step (2), when the low-carbon ferromanganese is used for regulating Mn, C: 0.20 to 0.70 percent; mn: 80.0% -90.0%; the balance being impurity S, P.
Wherein: in the step (7), the heating coefficient corresponding to the temperature is as follows: heating coefficient =1.65- (corresponding to temperature-860) × 0.005; the heat preservation time is 5-30 min.
The invention has the advantages that: the steel provided by the invention has stable comprehensive mechanical properties, better strength, plasticity and toughness, and meets the requirement of H resistance2Corrosion by SThe performance requirement and the design requirement of the low-crack sensitivity steel are completely met; under the condition of pure fire, the high strength and high toughness of the material can be ensured, and the H resistance of the material can be ensured2S corrosion performance. Compared with the prior steel, the steel of the invention resists H2The corrosion performance of S is greatly improved, and the HIC performance and the SSC loading stress capacity are obviously improved; can be widely applied to wet H2S in corrosive environment. The steel material of the invention integrates high strength, high toughness and H resistance under the normalizing condition2The S corrosion performance is integrated, the method can provide reference for the development of multipurpose multifunctional composite high-strength low-alloy steel in the future, and the method has a larger application space. The method can stably produce the normalized H-resistant steel with high strength and toughness through reasonable component proportion and process control process2The S corrosion steel has small fluctuation of yield strength and tensile strength, both within 60MPa, and small dispersion of material strength.
Drawings
FIG. 1 is a graph of simulated austenitization process temperature and phase composition comparison; (wherein the left figure shows the lower limit of the component and the right figure shows the upper limit of the component)
FIG. 2 is a line graph of the heating coefficient of the furnace during normalizing;
FIG. 3 is a typical microstructure after normalization;
FIG. 4 shows the internal quality of a slab of the example;
FIG. 5 shows the appearance of the HIC (left) and SSC (right) resistant samples after corrosion.
Detailed Description
The invention discloses a hydrogen sulfide corrosion resistant high-strength toughness normalized steel, which comprises the following chemical components (by weight percent): 0.08-0.11%; si: 0.25 to 0.40 percent; mn: 1.30-1.40%; cr: 0.20-0.30%; nb: 0.030-0.045%; ti: 0.010-0.020%; and (3) Alt: 0.020-0.040%; p: less than or equal to 0.012 percent; s: less than or equal to 0.0020 percent; n: less than or equal to 0.0045 percent; h: less than or equal to 0.0002 percent; ca: 0.0025-0.0040%; the balance of Fe and inevitable impurities, the carbon equivalent CEV is required to be in the range of 0.34-0.39%, and the welding crack sensitivity index Pcm is in the range of 0.16-0.19%.
C is a conventional strengthening element and is also an economic element, but it is a pairToughness and weldability are detrimental. As the content of C increases, carbide segregation is easy to occur, so that the hardness of the segregation zone is different from that of the surrounding tissues to resist H2S is not easy to corrode; comprehensively considering C to the structure, mechanical property and H resistance of the normalized steel2Influence of S corrosion performance, the content range of C in the scheme is 0.08-0.11%.
Mn mainly plays a role of solid solution strengthening. In the case of the same C content, as the Mn content increases, the strength increases and the brittle transition temperature decreases. Mn also plays a role in lowering the transformation temperature and contributes to grain refinement, so Mn is an indispensable element. However, too high Mn content results in a decrease in toughness, a severe band-like texture, an increase in anisotropy, and a decrease in H resistance2S corrosion performance. Therefore, controlling the Mn content in the steel improves the H resistance of the steel2S corrosion performance is of great significance. The Mn content range of the scheme is 1.30-1.40%.
Si also has a suitable solid solution strengthening effect, and can raise the γ → α phase transition temperature and promote the formation of proeutectoid ferrite. The main function of Si is deoxidation, and the Si is added with Al, so that the oxygen in steel can be eliminated during steel making and refining. Al is also an important metallurgical element, is extremely easy to oxidize, and forms compact Al on the surface of a substrate after oxidation2O3The film can prevent the substrate covered with the oxide film from further changing. The content ranges of Si and Al are 0.25-0.40% and 0.020-0.040%, respectively.
Among the alloy elements, Cu has the most obvious effect on hydrogen induced cracking, promotes the formation of a passive film, reduces the invasion of H, and prevents the formation of the hydrogen induced cracking. Ni is an element capable of improving impact toughness, and simultaneously, Ni can also reduce the harmful effect of Cu on hot brittleness; in the presence of H2In the acid gas environment of S, Ni also has the function of reducing the hydrogen absorption rate. However, in order to reduce the problem of production cost increase caused by the introduction of precious alloys, on the basis of the existing component design, on the premise of ensuring the toughness index of the normalized material, the invention selects not to add Ni and Cu.
Compared with Mn, Ni and Cu reduce the temperature range of delta-Fe, Cr keeps the temperature range of delta-Fe, increases the retention time of a delta-Fe high-temperature phase region, is beneficial to improving solute diffusion, promotes segregation redistribution of a casting structure, and therefore the hardness of a center line structure is lower, and the HIC resistance result is improved. The invention selects and adds proper Cr, the content range is 0.20-0.30%.
S is the influence of the steel on H resistance2S main elements of corrosion. When the S content in the steel is greater than 0.005%, the sensitivity of HIC significantly increases as the S content increases. When the S content in the steel is less than 0.002%, HIC is significantly reduced, even negligible. Since S is easily combined with Mn to generate MnS inclusions, Mn has a large influence on S segregation in steel, and the form and distribution of the sulfide Mn inclusions are directly influenced by the content of Mn. At H2In the S corrosion environment, the content of S in steel must be controlled in order to achieve an ideal corrosion resistance effect. P is highly segregated in the solidification process, and the segregation of the central P can be 10 times or 20 times of the actual P content in the steel; p segregation also promotes hydrogen induced crack formation. By combining the above analysis, the invention requires that the S content is less than or equal to 0.0020 percent and the P content is less than or equal to 0.012 percent.
The microalloying elements Nb, V and Ti mainly play a role in fine grain strengthening and precipitation strengthening. Nb limits the austenite grains to grow and refines the grains, thereby improving the strength and the toughness of the material. Ti carbon-nitrogen compounds are distributed on austenite crystal boundaries, particularly TiN can prevent austenite crystal grains from growing in heating; free nitrogen in the steel is eliminated due to the formation of insoluble TiN, thereby also improving the toughness of the steel. Compared with Nb and Ti, V has lower dissolution temperature, delays recrystallization only below 900 ℃, and has slight tissue refining effect and certain precipitation strengthening effect. In combination with the above analysis, the invention selects Nb and Ti as fine crystal elements, wherein the Nb content is 0.030-0.045%, and the Ti content is 0.010-0.020%.
Ca can improve the form and distribution of oxide, sulfide and carbide inclusions, and improve the cleanliness of steel in the metallurgical process. During Ca treatment of Al killed steel, O and S in the steel compete to react with Ca to convert Al2O3Conversion to calcium aluminate; the CaO-rich aluminate inclusions have a high S capacity and can absorb S in steel. When molten steel is solidified and cooled, the solubility of S in the inclusions is reduced, CaS is precipitated, and composite inclusions with calcium aluminate at the core and MnS and CaS surrounded by shells are formed. It has high melting point, no extension during rolling, and can eliminate MnAdverse effects of S. The scheme has the following content range of Ca: 0.0025-0.0040%, preferably the Ca content is in the range: 0.0030 to 0.0040 percent; meanwhile, the Ca/S ratio is required to be more than or equal to 1.25.
The invention also discloses a manufacturing method of the hydrogen sulfide corrosion resistant high-strength toughness normalizing steel, which comprises the steps of molten iron pretreatment, converter smelting, LF furnace refining, RH vacuum treatment, continuous casting billet casting, continuous casting billet heating and rolling and normalizing heat treatment, and specifically comprises the following steps:
(1) the molten iron pretreatment adopts a deep desulfurization mode, 500kg of small-particle lime is added at the bottom of a ladle, the initial S content is set according to the actual value by 1.2 times, and the target S content is set according to the proportion of less than or equal to 0.003 percent; the Mg spraying amount is 10kg more than the theoretical calculation amount so as to ensure the S removing effect. And after the blowing is finished, carrying out slag skimming operation, skimming for 4-5min, adding 60-80kg of slag conglomeration agent, and skimming for 3-4min after stopping for 2min, wherein the net slag skimming time is ensured to be more than or equal to 7min, and the bright surface reaches more than 95% after the slag skimming.
(2) A converter process: the tapping temperature of the converter is 1650 +/-20 ℃; ensuring that endpoint C, S, P is satisfactory. Adopting high-quality low-S scrap steel to reduce the return of S; a double-slag method is adopted, C is pulled at low temperature to remove P, and C is removed by post-blowing, wherein the post-blowing rate is 100%. The blowing process adopts a bottom blowing argon mode, and the initial bottom blowing argon flow is 420 +/-10 m3Flow rate of bottom blowing argon 520 +/-10 m at the final stage of converting3H is used as the reference value. When 1/3 steel is tapped, lime (2.5-2.8 kg/ton molten steel) and fluorite (0.05-0.06 kg/ton molten steel) are added along with the steel flow for slag washing. After tapping, adding aluminum grates (0.03-0.04 kg/ton molten steel) on the slag surface.
(3) And (3) refining in an LF furnace: the Mn (wherein C is 0.20-0.70%, Mn is 80.0-90.0%, and the balance is S, P) is adjusted by using low-carbon ferromanganese, the deoxidation and aluminum adjustment by using aluminum iron are forbidden in the treatment process, and aluminum particles are used for adjusting aluminum. LF end temperature 1635. + -. 10 ℃. The Al content at the end of LF is controlled according to 0.020-0.050%, and the total aluminum adjusting amount of the LF furnace is not more than 5 kg/ton molten steel. Adding ferrotitanium to adjust Ti before the LF is discharged from the LF furnace, wherein the reference absorption rate is 80-85%. anti-H2The steel for S corrosion has strict S, P content requirement, and the LF treatment period needs to be prolonged. A double-slag method, a large-slag-quantity, high-alkalinity and low-temperature tapping process is adopted to ensure that the P content is between 0.005 and 0.006 percent; adopts a deep desulfurization process and a low-S steel vacuum rinsing chamber process, and reduces the processThe process is continued to return to S, and the content of S is ensured to be between 0.0006 and 0.008 percent. Adopts calcification treatment, wherein a Si-Ca line of 300-.
(4) RH vacuum treatment process: the RH processing finishing temperature is 1585 +/-5 ℃, and the soft blowing finishing temperature is 1565 +/-5 ℃. The argon flow is increased to 800-1200 NL/min, and the deep vacuum treatment time is guaranteed to be more than or equal to 15min (target 16 min); after the final batch of alloy is adjusted, the vacuum treatment time is required to be more than or equal to 5min (target 6 min). And (5) after the vacuum is finished, hydrogen determination is carried out. And (3) soft blowing is carried out on the molten steel before the ladle is hung, the flow of soft argon blowing is controlled to be less than or equal to 100L/min, the slag surface cannot be turned over, the soft blowing time of the molten steel is guaranteed to be more than or equal to 12min (15 min of target), and the molten steel calming time after the soft blowing is more than or equal to 5min (6 min of target).
(5) And (3) casting a continuous casting blank: the superheat degree of molten steel is reduced, and a low drawing speed and soft reduction process is adopted to ensure the casting effect and the core quality of the continuous casting billet. Adopting a blank of 300mm multiplied by 2000mm, the drawing speed is 0.75-0.85m/min, and the average superheat degree is less than or equal to 25 ℃. The reduction of the two-phase area and the solid phase area is increased under dynamic light pressure, the maximum reduction rate is 1.30mm/m, the maximum reduction of the two-phase area is 8mm, and the maximum reduction of the solid phase area is 1 mm.
(6) Heating and rolling a continuous casting blank: to reduce the segregation of C, Mn, P, S and other elements and reduce the resistance of the band-shaped structure or inclusion to H2S, adverse influence of corrosion performance, and the processes of high-temperature heating of a continuous casting billet, large reduction in the rolling process, strong water cooling after rolling and the like are adopted. The heating process adopts a walking beam type heating furnace, the heating soaking temperature is 1220-1260 ℃ (the target soaking temperature is 1240 ℃), and the in-furnace time is 280-360 min (the target in-furnace heating time is 320 min) so as to ensure the full austenitizing of the continuous casting billet. In the rolling process, a controlled rolling control process is adopted, the rolling finishing temperature of the recrystallization zone is required to be 1000-1050 ℃, and the thickness to be heated is 2.0-4.5 times of the thickness of a finished steel plate. The total reduction rate of the rolling stage in the recrystallization zone is more than or equal to 60 percent, and in the longitudinal rolling process after widening, the single-pass reduction rate presents an increasing mode, and the single reduction of the last 2 passes of rolling in the recrystallization zone is required to be more than or equal to 35 mm. The rolling start temperature of the non-recrystallization zone is 860 ℃ and 920 ℃,the rolling finishing temperature of the non-recrystallization zone is 800-; the single-pass reduction rate of all passes before the last 2 passes of rolling in the non-recrystallization region is more than or equal to 10 percent, the reduction of the last two passes is less than or equal to 5mm, and the surface quality of the rolled steel plate is ensured while fully crushing austenite grains. After the steel plate is rolled, the steel plate quickly enters a cooling device for cooling, the water inlet temperature is 770-800 ℃, the final cooling temperature is 550-600 ℃, and the cooling speed is 15-25 ℃/S. And (3) rapidly performing off-line stack cooling after the steel plate is rolled, wherein the stack cooling temperature range is 400-500 ℃, and the stack cooling time range is 24-48 h.
(7) Normalizing heat treatment procedure: combining the designed components, adopting a metal phase diagram and material performance calculation software JMat-Pro, referring to the heating capacity of a normalizing furnace in the actual industrial production process, simulating the austenitizing process temperature and phase composition, and calculating the complete austenitizing temperature Ac3 to be 852-856 ℃ according to the upper limit and the lower limit of component design on the premise of 'the soaking temperature of 900 ℃, the heating speed of 0.30 ℃/s and the heat preservation time of 15 min'. Results of the austenitizing simulation process are shown in figure 1. The proposal requires that the normalizing temperature is increased by 10-20 ℃ on the basis of the austenitizing temperature, namely the normalizing temperature is 862-. In the normalizing process, the total in-furnace time (= heating furnace coefficient x steel plate thickness + heat preservation time), wherein the heating furnace coefficient is executed according to the attached figure 2, the heating coefficient is 1.65min/mm when the normalizing is carried out at 860 ℃, the heating coefficient is 1.60min/mm when the normalizing is carried out at 870 ℃, and the heating coefficient is 1.55min/mm when the normalizing is carried out at 880 ℃; according to the thickness of the steel plate, the heat preservation time is as follows: 5-30 min.
In the scheme, the steel material has H resistance2The corrosion performance test method comprises the following steps: one longitudinal sample is taken at each of the width 1/4, 1/2 and the edge of the steel plate, and the sample size is as follows: t (thickness) × 20mm (width) × 100mm (roll direction), the test was carried out according to the A test solution standard of NACE TM 0284 for 96 hours. And (4) acceptance standard: average of three sections: the Crack Sensitivity Rate (CSR) is less than or equal to 1 percent, the Crack Length Rate (CLR) is less than or equal to 10 percent, and the Crack Thickness Rate (CTR) is less than or equal to 3 percent.
Taking one longitudinal sample from each of the width 1/2 of the steel plate and the edge of the steel plate; sample size: the test piece is more than or equal to 115mm (length) multiplied by 15mm (width) multiplied by 5mm (thickness), a 4-point bending test is carried out in NACE TM 0177 solution A according to the ASTM G39 standard, the test time is 720 hours, and the loading stress of the test piece is 90 percent of the actual yield strength. And (4) acceptance standard: the sample was observed under a microscope at a magnification of 10 times without any cracks on the surface of the sample.
The H-resistant product produced by the process flow2The S-corrosion high-strength toughness normalized steel has stable comprehensive mechanical properties, better strength, plasticity and toughness, and meets the requirement of H resistance2The corrosion performance requirement of S is met, and simultaneously, the design requirement of low-crack sensitivity steel is completely met; the mechanical performance indexes are as follows: the yield strength is more than or equal to 355MPa and less than or equal to 415MPa, the tensile strength is more than or equal to 500MPa and less than or equal to 560MPa, the elongation after fracture is more than or equal to 30.0 percent and less than or equal to 45.0 percent, and the longitudinal impact at the temperature of between 80J and 60 ℃ is less than or equal to 200J; the high-strength high-toughness normalized steel has excellent H resistance2The S has excellent corrosion performance, wherein the HIC resistance indexes of CSR, CLR and CTR are all 0; SSC performance index-macroscopically three parallel specimens were free of cracks perpendicular to the direction of surface tensile stress. Typical microstructures after normalization were ferrite (ratio > 80) + pearlite (ratio < 20%), see fig. 3.
Example 1
According to the invention2The chemical composition range of the S corrosion high-strength toughness normalizing acid-resistant steel meets the requirement, and molten steel smelting, continuous casting billet casting, steel plate rolling and normalizing heat treatment are completed on a 5000mm wide and thick plate production line. And (3) blank molding of the continuous casting blank: 300mm 2000mm 3350 mm; specification of rolled steel plate: 30mm 2600mm 12000mm, 2-point.
The specific process parameters of the embodiment are controlled as follows:
the molten iron pretreatment adopts a deep desulfurization mode, 505kg of small-particle lime is added at the bottom of a ladle, 11kg of more sprayed Mg is added, and the S removal effect is ensured. In the slag skimming operation, the net slag skimming time is 8min, and the bright surface reaches 100 percent after slag skimming;
the after-blowing rate in the converter smelting process is 100 percent; the tapping temperature of the converter is 1657 ℃, and the initial bottom blowing argon flow is 430m3Flow rate of bottom-blown argon at the final stage of converting 515m3H is used as the reference value. 2.8kg of lime and 0.05kg of fluorite were added to the steel stream for slag washing when 1/3 steel was tapped. After tapping, 0.04kg of aluminum grate is added on the slag surface；
The LF finishing temperature is 1638 ℃, the Alt content at the LF finishing is 0.033%, and the total Al content of the LF furnace is adjusted to be 4.4 kg/ton of molten steel. The P content is 0.012%; a deep desulfurization process is adopted, and the S content is 0.0015%; feeding 350m of Si-Ca wire and 200 m of Ca wire, wherein the Ca/S ratio is =2.0, and the Ca content is 30 ppm;
the RH treatment finishing temperature is 1588 ℃, the soft blowing finishing temperature is 1560 ℃, the argon flow is 1000NL/min, and the deep vacuum treatment time is 17 min; after the alloy adjustment is finished, the vacuum treatment time is 6 min; soft argon blowing flow is 60L/min, soft blowing time is 12min, and molten steel after soft blowing is calmed for 5 min;
a300 mm × 2000mm blank is used, the drawing speed is 0.80m/min, the superheat degree is 23 ℃, the two-phase area reduction is 7.5mm, and the solid-phase area reduction is 0.8 mm. Through means of low drawing speed, superheat degree control, dynamic light pressing and the like, the center segregation level is controlled to be C-type 1.0, the internal quality is good, and the macroscopic morphology of the internal quality of the continuous casting billet is shown in an attached figure 3. The low power rating of the slab is shown in table 1.
The actual composition of the strand in the examples is shown in Table 2. The actual smelting components meet the design requirements.
The heating soaking temperature of the continuous casting billet is 1335 ℃, and the in-furnace time is 315 min. In the rolling process, the rolling finishing temperature of the recrystallization zone is 1035 ℃, and the thickness is 90.2 mm. The rolling start temperature of the non-recrystallization zone is 860 ℃ and 920 ℃ and the rolling end temperature of the non-recrystallization zone is 820 ℃. After the steel plate is rolled, the water inlet temperature is 793 ℃, the final cooling temperature is 556 ℃, and the cooling speed is 20.5 ℃/S. The heap cooling temperature is 450 ℃, and the heap cooling time range is 36 h. In the rolling stage of the recrystallization zone, the rolling reduction of the 5 th pass, the rolling reduction of the 6 th pass and the rolling reduction of the 7 th pass are respectively 36.5mm, 39.2mm and 35.2mm, the single-pass reduction rate presents an increasing trend, and the total reduction rate is 69.9 percent; in the rolling stage of the non-recrystallization zone, the single-pass reduction rate is over 10% in the 8 th to 12 th passes, the single-pass reduction amounts in the 13 th and 14 th passes are 4.2mm and 1.5mm, and the total reduction rate is 66.6%; the detailed rolling schedule of the examples is shown in table 3. In the normalizing heat treatment process, the actual normalizing temperature is 865 ℃, the heating coefficient is 1.60min/mm, the heat preservation time is 15min, and the total in-furnace time is 63 min.
The steel sheets of this example have comprehensive mechanical properties as shown in Table 4. The normalized steel has good mechanical property and meets the performance index requirement of the high-strength and high-toughness normalized steel.
Examples anti-H2The appearance and appearance of the S corrosion are shown in figure 5. After passing HIC and SSC tests, the appearance color of the surface of the sample is normal, and no cracks or other defects exist.
The anti-HIC test conditions and results are shown in Table 5. After 96h of test, the surface of the steel plate base material sample to be tested has no hydrogen bubbles, and the Crack Sensitivity Rate (CSR), the Crack Length Rate (CLR) and the Crack Thickness Rate (CTR) of the sample are all 0.
The SSC resistance test conditions are shown in Table 6; after the 720-hour test, the loading stress was 347.4MPa (386 MPa by 90%), and no cracks in the direction perpendicular to the surface tensile stress were observed by macroscopic examination of all three parallel specimens, and no cracks were observed by examination with a 10-fold magnifying glass.
In summary, the H-resistance produced by the method of the invention2The S-corrosion high-strength toughness normalized steel has stable comprehensive mechanical properties, better strength, plasticity and toughness, and meets the requirement of H resistance2The corrosion performance requirement of S is met, and simultaneously, the design requirement of low-crack sensitivity steel is completely met; the mechanical performance indexes are as follows: the yield strength is more than or equal to 355MPa and less than or equal to 415MPa, the tensile strength is more than or equal to 500MPa and less than or equal to 560MPa, the elongation after fracture is more than or equal to 30.0 percent and less than or equal to 45.0 percent, and the longitudinal impact at the temperature of between 80J and 60 ℃ is less than or equal to 200J; the high-strength high-toughness normalized steel has excellent H resistance2The S has excellent corrosion performance, wherein the HIC resistance indexes of CSR, CLR and CTR are all 0; SSC performance index-macroscopically three parallel specimens were free of cracks perpendicular to the direction of surface tensile stress.
Claims (4)
1. A manufacturing method of normalized steel with hydrogen sulfide corrosion resistance and high strength and toughness is characterized in that:
the normalizing steel comprises the following components in percentage by weight: c: 0.08-0.11%; si: 0.25 to 0.40 percent; mn: 1.30-1.40%; cr: 0.20-0.30%; nb: 0.030-0.045%; ti: 0.010-0.020%; and (3) Alt: 0.020-0.040%; p: less than or equal to 0.012 percent; s: less than or equal to 0.0020 percent; n: less than or equal to 0.0045 percent; h: less than or equal to 0.0002 percent; ca: 0.0025-0.0040%; the balance of Fe and inevitable impurities; wherein, the range of the carbon equivalent CEV is 0.34-0.39%, and the range of the welding crack sensitivity index Pcm is 0.16-0.19%;
the manufacturing method comprises the following steps:
(1) a molten iron pretreatment step: adopting a deep desulfurization mode, adding 500kg of small-particle lime at the bottom of a ladle, setting the initial S content according to the actual value by 1.2 times, and setting the target S content to be less than or equal to 0.003%; the quantity of sprayed Mg is 10kg more than that of theoretical calculation, slag skimming operation is carried out after the spraying is finished, slag is skived for 4-5min, then 60-80kg of slag conglomeration agent is added, and the skimming is carried out for 3-4min after the blowing is stopped for 2min, so that the net slag skimming time is guaranteed to be more than or equal to 7 min;
(2) a converter smelting step: the tapping temperature of the converter is 1650 +/-20 ℃; adopting a double-slag method, pulling C at low temperature to remove P, and then blowing to remove C, wherein the post-blowing rate is 100%; the blowing process adopts a bottom blowing argon mode, and the initial bottom blowing argon flow is 420 +/-10 m3Flow rate of bottom blowing argon 520 +/-10 m at the final stage of converting3H; when the steel is tapped at 1/3, lime and fluorite are added along with the steel flow for slag washing; after tapping, adding an aluminum grate on the slag surface;
(3) and (3) refining in an LF (ladle furnace): regulating Mn with low-carbon ferromanganese, wherein the LF finishing temperature is 1635 +/-10 ℃; controlling the Al content at the end of LF according to 0.020-0.050%, wherein the total aluminum adjusting amount of the LF is not more than 5 kg/ton of molten steel; adding ferrotitanium to adjust Ti before the LF is discharged, wherein the absorption rate is 80-85%; the content of P is between 0.005 and 0.006 percent; the content of S is between 0.0006 and 0.008 percent; the Ca content is between 25 and 40ppm, and the value of Ca/S is more than 1.25;
(4) RH vacuum treatment step: the RH processing ending temperature is 1585 +/-5 ℃, and the soft blowing ending temperature is 1565 +/-5 ℃; the argon flow is increased to 800-1200 NL/min, and the deep vacuum treatment time is guaranteed to be more than or equal to 15 min; after the final batch of alloy is adjusted, the vacuum treatment time is required to be more than or equal to 5 min; after the vacuum is finished, hydrogen determination is carried out; soft blowing is carried out on the molten steel before the ladle is hung, the flow of soft argon blowing is controlled to be less than or equal to 100L/min, the slag surface cannot be turned over, the soft blowing time of the molten steel is ensured to be more than or equal to 12min, and the molten steel calming time after the soft blowing is more than or equal to 5 min;
(5) and (3) casting a continuous casting blank: adopting a blank with the thickness of 300mm multiplied by 2000mm, the drawing speed is 0.75-0.85m/min, and the average superheat degree is less than or equal to 25 ℃; the reduction of the two-phase area and the solid phase area is increased under dynamic light pressure, the maximum reduction rate is 1.30mm/m, the maximum reduction of the two-phase area is 8mm, and the maximum reduction of the solid phase area is 1 mm;
(6) heating and rolling a continuous casting blank: a walking beam type heating furnace is adopted in the heating process, the heating soaking temperature is 1220-1260 ℃, and the in-furnace time is 280-360 min, so as to ensure the full austenitization of the continuous casting billet; in the rolling process, a controlled rolling control process is adopted, the rolling finishing temperature of the recrystallization zone is required to be 1000-1050 ℃, and the thickness of the temperature to be kept is 2.0-4.5 times of the thickness of the finished steel plate; the total reduction rate of the rolling stage in the recrystallization zone is more than or equal to 60 percent, and in the longitudinal rolling process after widening, the single-pass reduction rate presents an increasing mode, and the single reduction of the last 2 passes of rolling in the recrystallization zone is required to be more than or equal to 35 mm; the rolling starting temperature of the non-recrystallization zone is 860-920 ℃, the rolling finishing temperature of the non-recrystallization zone is 800-840 ℃, and the total reduction rate of the rolling stage of the non-recrystallization zone is more than or equal to 50 percent; the single-pass reduction rate of all passes before the last 2 passes of rolling in the non-recrystallization region is more than or equal to 10 percent, the reduction of the last two passes is less than or equal to 5mm, after the steel plate is rolled, the steel plate quickly enters a cooling device for cooling, the water inlet temperature is 770-; rapidly performing off-line stack cooling after the steel plate is rolled, wherein the stack cooling temperature range is 400-500 ℃, and the stack cooling time range is 24-48 h;
(7) normalizing heat treatment: the normalizing temperature is 862-876 ℃; the total in-furnace time during the normalizing process = heating coefficient x steel plate thickness + holding time.
2. The method of claim 1, wherein: in the step (2), the addition amount of the lime is 2.5-2.8 kg/ton of molten steel, the addition amount of the fluorite is 0.05-0.06 kg/ton of molten steel, and the addition amount of the aluminum grate is 0.03-0.04 kg/ton of molten steel.
3. The method of claim 1, wherein: in the step (2), when the low-carbon ferromanganese is used for regulating Mn, C: 0.20 to 0.70 percent; mn: 80.0% -90.0%; the balance being impurity S, P.
4. The method of claim 1, wherein: in the step (7), within the range of the normalizing temperature 862-876 ℃, the heating coefficients corresponding to the temperatures are as follows: heating coefficient =1.65- (corresponding to temperature-860) × 0.005; the heat preservation time is 5-30 min.
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006291348A (en) * | 2005-03-17 | 2006-10-26 | Jfe Steel Kk | Low yield-ratio high-tensile steel having excellent weldability, and its production method |
| CN102653844A (en) * | 2011-03-03 | 2012-09-05 | 中国石油天然气集团公司 | Electric-resistance-welded steel pipe resisting acidic environment corrosion and preparation method thereof |
| CN102732783A (en) * | 2012-06-15 | 2012-10-17 | 攀钢集团成都钢钒有限公司 | H2S corrosion-resistant steel and preparation method thereof |
| CN102925814A (en) * | 2012-11-28 | 2013-02-13 | 武汉钢铁(集团)公司 | Steel for hydrogen sulfide stress corrosion resisting pressure container and production method of steel |
| JP2015163730A (en) * | 2014-01-28 | 2015-09-10 | 株式会社神戸製鋼所 | Low-yield-ratio high-strength steel sheet high in work hardenability and excellent in uniform elongation and weldability and production method thereof |
| CN105603304A (en) * | 2016-01-15 | 2016-05-25 | 宝山钢铁股份有限公司 | Q370R pressure vessel applicable thick steel plate with good HIC (hydrogen induced cracking) and SSCC (sulfide stress corrosion cracking) resistance and manufacture method thereof |
| CN105925899A (en) * | 2016-07-13 | 2016-09-07 | 达力普石油专用管有限公司 | Quenched and tempered X52 hydrogen sulfide corrosion resisting seamless line pipe and preparation method thereof |
| CN106435396A (en) * | 2016-09-09 | 2017-02-22 | 武汉钢铁股份有限公司 | High temperature-resistant and hydrogen sulfide corrosion-resistant steel plate for pressure vessels and manufacturing method thereof |
| CN106756536A (en) * | 2016-11-26 | 2017-05-31 | 江阴兴澄特种钢铁有限公司 | A kind of automobile-used low-alloy steel of the normalizing type of resistance to hydrogen-type corrosion movable tank and preparation method thereof |
| CN108342649A (en) * | 2018-03-27 | 2018-07-31 | 武汉钢铁有限公司 | A kind of quenched steel for high strength pressure vessel and production method of acid corrosion-resistant |
| CN109923237A (en) * | 2016-11-11 | 2019-06-21 | 株式会社Posco | Pressure vessel steel and its manufacturing method with excellent hydrogen-induced cracking resistance |
-
2020
- 2020-07-31 CN CN202010756299.9A patent/CN111926253B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006291348A (en) * | 2005-03-17 | 2006-10-26 | Jfe Steel Kk | Low yield-ratio high-tensile steel having excellent weldability, and its production method |
| CN102653844A (en) * | 2011-03-03 | 2012-09-05 | 中国石油天然气集团公司 | Electric-resistance-welded steel pipe resisting acidic environment corrosion and preparation method thereof |
| CN102732783A (en) * | 2012-06-15 | 2012-10-17 | 攀钢集团成都钢钒有限公司 | H2S corrosion-resistant steel and preparation method thereof |
| CN102925814A (en) * | 2012-11-28 | 2013-02-13 | 武汉钢铁(集团)公司 | Steel for hydrogen sulfide stress corrosion resisting pressure container and production method of steel |
| JP2015163730A (en) * | 2014-01-28 | 2015-09-10 | 株式会社神戸製鋼所 | Low-yield-ratio high-strength steel sheet high in work hardenability and excellent in uniform elongation and weldability and production method thereof |
| CN105603304A (en) * | 2016-01-15 | 2016-05-25 | 宝山钢铁股份有限公司 | Q370R pressure vessel applicable thick steel plate with good HIC (hydrogen induced cracking) and SSCC (sulfide stress corrosion cracking) resistance and manufacture method thereof |
| CN105925899A (en) * | 2016-07-13 | 2016-09-07 | 达力普石油专用管有限公司 | Quenched and tempered X52 hydrogen sulfide corrosion resisting seamless line pipe and preparation method thereof |
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| CN109923237A (en) * | 2016-11-11 | 2019-06-21 | 株式会社Posco | Pressure vessel steel and its manufacturing method with excellent hydrogen-induced cracking resistance |
| CN106756536A (en) * | 2016-11-26 | 2017-05-31 | 江阴兴澄特种钢铁有限公司 | A kind of automobile-used low-alloy steel of the normalizing type of resistance to hydrogen-type corrosion movable tank and preparation method thereof |
| CN108342649A (en) * | 2018-03-27 | 2018-07-31 | 武汉钢铁有限公司 | A kind of quenched steel for high strength pressure vessel and production method of acid corrosion-resistant |
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