CN113621873A - Weather-resistant structural steel with stabilized rust layer and preparation method thereof - Google Patents
Weather-resistant structural steel with stabilized rust layer and preparation 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
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/004—Very low carbon steels, i.e. having a carbon content of less than 0,01%
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
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- 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
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
- C22C33/06—Making ferrous alloys by melting using master alloys
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- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
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- 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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- 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
- C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
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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
- C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
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Abstract
A weather-resistant structural steel with a stabilized rust layer and a preparation method thereof are disclosed, and the weather-resistant structural steel comprises the following chemical components in percentage by mass: less than or equal to 0.15% of C, less than or equal to 0.20% of Si, 0.80-1.20% of Mn, 0.040-0.070% of P, less than or equal to 0.003% of S, 0.35-0.45% of Ni, 0.22-0.32% of Cu, 0.015-0.030% of Ce, 0.02-0.10% of Sb, and the balance of Fe and inevitable impurity elements; during preparation, firstly preparing a steel plate through smelting, rolling and cooling processes, and then stabilizing the rust layer of the steel plate to obtain the steel plate; the preparation process disclosed by the invention is simple in flow, low in production cost, green and environment-friendly, strong in operability, and capable of quickly and economically forming the weather-resistant structural steel with the stabilized rust layer, and the formation time of the stabilized rust layer is within the manufacturing period of the steel structure, so that the manufacturing requirements of structural members such as buildings, towers, ocean platforms and the like are met.
Description
Technical Field
The invention relates to the technical field of steel manufacturing, in particular to weather-resistant structural steel with a stabilized rust layer and a preparation method thereof.
Background
Corrosion of ferrous materials in the use environment medium is one of the major causes of material failure. Among them, steel is exposed to the atmosphere, and atmospheric corrosion caused by chemical and electrochemical actions of water, oxygen and the like in the atmosphere is the most common corrosion form of steel. The relevant data show that the steel material lost by corrosion in China is more than 1000 million tons per year, wherein the loss caused by atmospheric corrosion accounts for more than 50 percent. And with the aggravation of air pollution caused by the rapid development of the industry, the corrosion problem of the engineering structural steel used in the atmospheric environment is more serious.
The weathering steel is prepared by adding alloy elements such as copper, phosphorus, chromium, nickel, molybdenum, bismuth, antimony and the like into steel and adding a reasonable process to obtain good performance and proper structure and has good atmospheric corrosion resistance in different environments. In the application process, the surface form of the paint has three modes of bare coating, light coating and rust layer stabilization. Under the naked use mode, a compact and stable protective rust layer taking alpha-FeOOH as a main component is formed on the surface of the weathering steel through long-time dry-wet alternation, so that the penetration of an external corrosion medium is hindered, and the corrosion is slowed down. However, if the weathering steel is naturally exposed and used in the atmospheric environment, the generation time of the compact and stable protective rust layer is very long, generally 4-10 years are needed, and certain moisture, acidity and Cl are contained-Under the condition of severe corrosion environment, the time is longer and even longerSo that a stable rust layer cannot be formed, and the corrosion is seriously lost, thereby causing safety accidents. In addition, in the process of forming the stabilized rust layer, the problems of non-uniform color, rust liquid sagging, local pitting and the like appear on the exposed surface of the steel plate due to the environment, the structure, the climate and the like, thereby causing confusion to people.
In addition, in the coating and using process of the structural steel, the organic solvent in the paint contains a large amount of toxic and harmful substances, which can cause harm to human bodies and pollution to the environment. With the construction requirements of resource-saving and environment-friendly society, weather-resistant structural steel and a coating-free use technology thereof in a steel structure are favored. Before the invention is proposed, some of the related technologies relate to the stabilization of the weather-resistant structural steel and the rust layer thereof, but some of the related technologies do not consider the stabilized rust layer, have different stabilized rust layer forming modes, have overhigh cost and complicated production processes, and cannot meet the requirements of the market on the weather-resistant structural steel.
The Chinese invention patent application No. 201910359721.4 discloses a bare weathering steel with a stable rust layer and a manufacturing method thereof, and the patent discloses a bare weathering steel with a stable rust layer, wherein the surface of the bare weathering steel is provided with a rust layer formed within 2 h. In addition, the invention also discloses a manufacturing method of the bare weathering steel with the stable rust layer, which comprises the following steps: (1) cleaning the surface of the steel plate and removing residual moisture; (2) applying a reagent on the surface of the steel plate to convert the simple substance iron on the surface of the steel plate into iron in an ionic state; (3) spraying water on the surface of the steel plate to enable the surface of the steel to be soaked by the water film, spraying the water film again after the water film on the surface of the steel plate is dried, repeating the spraying and spraying steps for a plurality of times so as to enable the ionic-state iron to be hydrolyzed into iron hydroxide precipitate, and then dehydrating to form a rust layer. The bare weathering steel has an even rust layer, the rust layer is stable and compact, the corrosion resistance is excellent, the problems of uneven color and the like before the rust layer of the conventional weathering steel is stabilized in the prior art are solved, and the bare weathering steel can be directly used in a bare manner without any surface treatment on the use site. However, the patent does not clearly show the chemical composition of the bare weathering steel with a stable rust layer and the steel plate production process, and the process for stabilizing the rust layer of the base steel plate is emphasized.
The Chinese patent application No. 201610004995.8 discloses a method for treating the surface of weathering resistant steel, which comprises the following steps: 1) carrying out surface shot blasting treatment on the weather-resistant steel to ensure that the surface roughness of the weather-resistant steel is Ra2.50 mu m-Ra3.50 mu m; 2) and (3) oxidizing the weathering steel subjected to shot blasting at the high temperature of 250-350 ℃ for 1-4 h to obtain a compact reddish brown oxide layer. The oxide layer has an appearance color similar to that of the weathering steel after long-term service, and can promote the formation of a stable rust layer. The method has simple process, lower cost and environmental protection, and avoids the pollution of the common coating surface stabilizing coating method for rapid stabilization of the weathering steel to the environment. However, the patent does not specify the specific brand, chemical composition and steel type application range of the base steel plate, and only describes that the base steel plate is applicable to Cu-containing weathering steel, and in addition, the steel plate is oxidized at a high temperature of 250-350 ℃ for 1-4 h, so that blue brittleness is easy to occur, and the plasticity and toughness of the steel plate are reduced.
The Chinese invention patent application number 202010749761.2 discloses 600MPa grade high-corrosion-resistance weathering steel and a preparation method thereof, and the patent discloses that the steel comprises the following chemical components: according to weight percentage, C is less than or equal to 0.12 percent, Si: 1.20-2.00%, Mn is less than or equal to 1.50%, P: 0.060-0.150%, S is less than or equal to 0.015%, Cr: 2.90-3.70%, Ni: 0.10-0.40%, Cu: 0.20-0.60%, Als is more than or equal to 0.010%, and the balance is Fe and inevitable impurities. The atmospheric corrosion resistance index I of the high-corrosion-resistance weathering steel reaches 12.61-14.02, which is obviously higher than 6.0, and the excellent atmospheric corrosion resistance of the product is realized. Meanwhile, the corrosion rate of the alloy relative to Q355B is less than or equal to 25%, the yield strength is 600-670 MPa, the tensile strength is 850-950 MPa, the elongation A is more than or equal to 18%, and the impact value at minus 40 ℃ is more than or equal to 27J, so that the alloy can be used in a hot and humid area in an exposed manner, can be widely applied to the fields of buildings, bridge construction or vehicle manufacturing, and has good application value. However, the P content is too high, which is not favorable for the toughness and cold bending processing of the steel plate, the Cr content is too high, which is also unfavorable for the toughness, and simultaneously influences the welding processing and the toughness and plasticity of the welding joint, and the manufactured steel plate can not meet the requirements of the steel structures such as bridges and the like and buildings on the toughness and the welding performance of the steel plate.
In view of the above-mentioned shortcomings of the weathering steel in the prior art, the present invention provides a weathering structural steel with a stabilized rust layer and a preparation method thereof, which are the technical problems to be solved in the present invention.
Disclosure of Invention
The invention aims to provide weather-resistant structural steel with a stabilized rust layer and a preparation method thereof aiming at the problem that the current steel plate cannot meet the requirement of the market on the weather-resistant structural steel.
The invention is realized by the following technical scheme:
the invention relates to weather-resistant structural steel with a stabilized rust layer, which comprises the following chemical components in percentage by mass: less than or equal to 0.15% of C, less than or equal to 0.20% of Si, 0.80-1.20% of Mn, 0.040-0.070% of P, less than or equal to 0.003% of S, 0.35-0.45% of Ni, 0.22-0.32% of Cu, 0.015-0.030% of Ce, 0.02-0.10% of Sb, and the balance of Fe and inevitable impurity elements.
Preferably, the chemical components and the mass percentage thereof of the invention are as follows: 0.08-0.14% of C, less than or equal to 0.20% of Si, 1.00-1.20% of Mn, 0.040-0.050% of P, less than or equal to 0.001% of S, 0.35-0.45% of Ni, 0.22-0.32% of Cu, 0.015-0.030% of Ce, 0.05-0.08% of Sb, and the balance of Fe and inevitable impurity elements.
Further, the chemical components and the mass percentage thereof of the invention are as follows: 0.10% of C, 0.12% of Si, 1.00% of Mn, 0.055% of P, 0.003% of S, 0.39% of Ni, 0.29% of Cu, 0.026% of Ce, 0.06% of Sb and the balance of Fe and inevitable impurity elements.
The invention discloses a preparation method of weather-resistant structural steel with a stabilized rust layer, which comprises the following steps:
(1) molten iron desulfurization, converter smelting and LF refining: adding molten iron into a molten iron tank, carrying out desulfurization treatment on the molten iron, then smelting in a top-bottom combined blown converter, and finally refining in a ladle furnace LF;
(2) and (3) RH furnace vacuum treatment: putting the refined molten iron into an RH furnace for vacuum treatment, adding Sb alloy in the treatment process, and ensuring that the net cycle time is more than or equal to 15min under the ultimate vacuum degree and the content of Sb at the end point meets the target requirement;
(3) protection pouring: the rare earth Re mixture containing Ce element is stably added into the crystallizer, and the rare earth element is utilized to change the inclusion characteristics of steel, thereby improving the toughness and fatigue performance of the steel;
(4) rough rolling and finish rolling: rolling the steel billet in two stages, wherein the initial rolling temperature of rough rolling is 1060-1160 ℃, and the thickness of the intermediate billet is 30-140 mm; the initial rolling temperature of finish rolling is not more than 945 ℃, the rolling thickness specification is 6-64 mm, and the final rolling temperature is 750-840 ℃;
(5) and (3) controlling cooling: controlling the starting cooling temperature to be 720-820 ℃, controlling the cooling speed to be 5-30 ℃/s, and controlling the temperature of red return to be 360-650 ℃;
(6) shot blasting treatment: placing the cooled steel plate in a shot blasting machine at normal temperature for shot blasting to remove the floating rust and the iron scale on the surface of the steel plate, wherein the shot blasting speed is 4-5.5 m/min, and the shot diameter is 0.8-1.8 mm, so that the surface quality of the steel plate reaches the AS 2.5-AS 3.0 level;
(7) and (3) quick rust treatment of the steel plate: flatly paving a steel plate on a track or a cooling bed with a lower water spraying header, then performing periodic watering action, automatically spraying water on the lower surface of the steel plate by using the header, automatically spraying water or manually spraying water on the upper surface of the steel plate for 3 times every 8 hours, keeping dry and wet alternation, and continuously spraying water for more than or equal to 7 days until a uniform yellow rust layer is produced on the surface of the steel plate;
(8) and (3) rust layer stabilization treatment: 5 to 10 mass percent of potassium phosphate solution is uniformly sprayed on the upper surface and the lower surface of the steel plate for stabilization treatment, and if the surface of the steel plate causes local damage in the later processing process, the potassium phosphate solution is adopted for repairing.
The reason for limiting the main chemical components of the weathering structural steel of the present invention is as follows:
the steel composition design of the invention has economical efficiency, the alloy element Cr added in the traditional weathering steel is cancelled, the microalloying element Nb or V is not added, the steel plate strength is ensured by C, Mn with proper content, the corrosion resistance of the steel is improved by adding corrosion resistance elements such as Cu, Ni, Sb, P and the like, and the comprehensive performance of the steel is improved by adding trace rare earth elements.
The element C is a guarantee of the strength of the steel. The strength of the steel is improved along with the increase of the carbon content, but the control difficulty of the center segregation of the casting blank is increased, the control difficulty of the ductility and toughness is increased, and the welding performance is also reduced. In order to ensure that the steel plate obtains good comprehensive performance, the carbon element content of the steel is designed to be less than or equal to 0.15 percent, and in order to take the strength and the toughness into consideration, and simultaneously, in consideration of low carbon equivalent, the carbon element content is preferably 0.08-0.12 percent.
Si is not combined with carbon in steel, but can be dissolved in ferrite to play a role of solid solution strengthening, so that the strength and the hardness of the ferrite are improved. The Si element is excessively added, so that the surface quality of the steel plate is poor, the formation of island-shaped martensite is promoted when the Si content is increased, and the toughness of a welding heat affected zone is damaged, so that the Si content is controlled to be less than or equal to 0.20 percent.
Mn is an important element of toughness in steel, but Mn element is easy to generate segregation in the core of a steel plate, so that the low-temperature toughness is reduced, and even the phenomenon of impact fracture delamination occurs. In order to ensure the strength of the steel plate and take toughness into consideration, the Mn content of the steel plate is designed to be 0.80-1.20%. In order to ensure the strength of the steel plate, the content of Mn is preferably 1.00-1.20%.
P is one of the harmful elements in steel. The phosphorus content is increased, the strength of the steel is improved, and the plasticity and the toughness are reduced. However, for the weathering structural steel, when P, Cu, Ni and the like are added into the steel in a compounding way, a good compounding effect can be shown, and the corrosion resistance of the steel can be obviously improved. Considering the application range of the steel and the requirement on the toughness and the plasticity of the steel, the content of the P element is designed to be 0.040-0.070%. In order to give consideration to cold-bending processability, toughness and plasticity and corrosion resistance, the content of the P element is preferably 0.040-0.050%.
S is an impurity element in steel. S element is easy to segregate and enrich in steel, and is not beneficial to the corrosion resistance of the steel plate; long-strip MnS inclusions are formed in the steel, and the impact toughness of the steel plate is reduced. The S element easily causes hot brittleness of the steel, resulting in a decrease in weldability, impact toughness, fatigue resistance, corrosion resistance, and the like of the steel. The level of sulfur content is therefore strictly controlled in the steel of the invention, i.e. S.ltoreq.0.003%, preferably S.ltoreq.0.001%.
The corrosion resistance of the steel can be improved by Cu, the compounds of Cu are enriched in the rust layer to isolate corrosion media, the corrosion of chloride ions and sulfate ions to a steel plate is reduced, meanwhile, the polarization resistance of the steel is increased by the compounds of Cu of the steel, the protection of the rust layer is enhanced, and the corrosion resistance of the steel is improved, so that the content of Cu is controlled to be 0.22-0.32%.
The Ni element can improve the stability and compactness of the rust layer, increase the bonding degree of the rust layer and the matrix, and avoid the peeling of the rust layer, thereby improving the corrosion resistance of the steel in severe environment. The Ni element can reduce the resistance of dislocation movement in the steel and reduce the internal stress in the steel, thereby improving the low-temperature toughness, so the Ni content of the steel is controlled to be 0.35-0.45%.
Rare earth element Ce (mainly referring to mixture of Re in the invention) can spheroidize Al2O3The inclusion improves the longitudinal and transverse impact properties of the steel and reduces the anisotropy of the steel, so the Ce content is controlled to be 0.015-0.030%.
Recent studies have shown that Sb element can improve the corrosion resistance of steel in industrial and rural environments, and that in marine environments, the corrosion resistance of Sb-containing steel increases as the PH of seawater decreases. However, the element Sb is disadvantageous to the strength and brittleness of steel. In consideration of insufficient brittleness and ductility of the Sb element, the steel of the present invention controls Sb to be 0.02 to 0.10%, preferably 0.05 to 0.08%.
The reason for setting the production process of the weather-resistant structural steel of the present invention is as follows:
(1) steel-smelting process
Cu and Ni alloys are added along with scrap steel during smelting in a converter, the LF refining time is ensured, S is fully removed, impurities are promoted to float to the maximum extent, and the production rhythm of the upper process and the lower process is coordinated through temperature rise and fall; sb is added in the RH process, the number of net circulation periods is ensured to reach 5-6, each net circulation treatment time is 2-3 min, H, O and other gas impurities in the steel are fully removed, and the guarantee is provided for obtaining good performance. And continuous casting is carried out for protective pouring, so that secondary oxidation of molten steel is reduced. Under the condition that the liquid level of the crystallizer is stable, a rare earth Re mixture of Ce element is added, and the rare earth element is utilized to change the inclusion characteristics of steel, so that the toughness and fatigue property of the steel are improved.
(2) Steel plate rolling and cooling process
Rough rolling and finish rolling: the rough rolling initial rolling temperature is 1060-1160 ℃, and the thickness of the intermediate blank is 30-140 mm; the initial rolling temperature of finish rolling is not more than 945 ℃, the rolling thickness specification is 6-64 mm, and the final rolling temperature is 750-840 ℃;
controlling cooling: controlling the starting cooling temperature to be 720-800 ℃, controlling the cooling speed to be 5-30 ℃/s, and controlling the temperature of red return to be 360-650 ℃;
the invention adopts the controlled rolling and controlled cooling process to produce the steel plate, and the delivery state of the steel plate is TMCP. The initial rolling temperature of rough rolling is 1060-1160 ℃, the thickness of the intermediate blank is selected to be 30-140 mm according to the thickness of the finished product, austenite grains are fully refined in a crystallization area through rolling austenite at high temperature and high pressure, and good toughness matching of the steel plate is guaranteed. And during finish rolling, rolling at the temperature of not more than 945 ℃, matching the rolling thickness specification of the finished steel plate to be 6-64 mm according to the thickness of the intermediate blank, controlling the finish rolling temperature to be 750-840 ℃, and rolling in a non-recrystallization area. The corresponding cooling temperature is controlled to be 720-800 ℃, and guarantee is provided for obtaining proper texture of the soft and hard phases. The cooling speed of the steel plate is controlled to be 5-30 ℃/s, and the temperature of red return is controlled to be 360-650 ℃. Under the guarantee of the process, the weather-resistant structural steel plate with excellent comprehensive performance is obtained.
(3) Steel plate rust layer stabilizing treatment process
Shot blasting treatment of steel plates: the defects of iron scale, iron dust, slag inclusion and the like on the surface of the steel plate can bring adverse effects on the stabilization of a rust layer and influence the uniformity of the rust layer. Meanwhile, the iron scale and the steel plate are contacted in a manner that the iron scale floats on the surface of the steel plate, the iron scale is embedded into the surface layer of the steel plate, the iron scale is adhered to the surface of the steel plate, and the iron scale is not a stable existing manner, particularly the embedded iron scale is often a source point of pitting corrosion of the steel plate. Therefore, shot blasting treatment of the steel plate is necessary to ensure that the steel plate achieves certain level of surface quality. The shot blasting process parameters selected by the steel are as follows: the shot blasting speed is 4-5.5 m/min, the shot diameter is 0.8-1.8 mm, and the surface quality of the steel plate reaches AS 2.5-AS 3.0 level;
quick rust treatment of the steel plate: spreading the steel plate on a track or a cooling bed with a lower water spraying header by a crane, and then periodically spraying waterThe lower surface of the steel plate adopts a collecting pipe to spray water automatically, the upper surface of the steel plate can spray water automatically or manually, the water is sprayed 1 time every 8 hours and 3 times every day, the alternation of dry and wet is kept, and the water is continuously sprayed for more than or equal to 7 days until a uniform yellow rust layer is produced on the surface of the steel plate. The steel quick-rusting process is simple and environment-friendly, only needs aqueous solution, and does not adopt any chemical reagent. The basic principle is as follows: in aqueous solution, the corrosion process of the weathering structural steel occurs as follows: fe → Fe2++2e-，1/2O2+H2O+2e-→2OH-，Fe+1/2O2+H2O→Fe(OH)2. In the rust layer, gamma-FeOOH and alpha-FeOOH are distributed, wherein the more alpha-FeOOH, the stronger the stability is, and the purpose of fast rust is to provide a uniform rust layer for the stabilization treatment of the next process rust layer in a short time. Through even steel plate full-surface fast rust treatment, a rust layer covering the full surface is formed on the surface of the steel plate in a short time, and the problems of uneven rust and local rust are avoided.
③ stabilizing and treating the rust layer: uniformly spraying 5-10% of potassium phosphate solution on the upper surface and the lower surface of the steel plate for stabilization; for the weathering structural steel, the rust layer formed rapidly cannot solve the problem of further corrosion of the substrate, and the rust layer needs to be stabilized to prevent the substrate from fully contacting with air, so that a compact rust layer mainly comprising alpha-FeOOH is formed on the surface of the weathering structural steel to hinder the substrate in the rust layer from further corrosion. 5 to 10 mass percent of potassium phosphate solution is taken as a stabilizer, when a steel plate is immersed in the stabilizer, anode dissolution occurs, and a compact FePO with good coverage is generated in a rust layer4And (5) passivating the film. The chemical reaction is as follows: PO (PO)4 3-+Fe3+→FePO4. The presence of the passive film prevents the corrosive medium from contacting the substrate under the layer of rust, and the corrosion of the substrate is slowed down until little corrosion occurs.
Repairing the rust layer: in the operation and the later processing, if the surface of the steel plate causes less local damage, 5 to 10 mass percent of potassium phosphate solution can be adopted for repairing.
Compared with the prior art, the invention has the following advantages:
(1) the preparation process disclosed by the invention is simple in flow, low in production cost, green and environment-friendly, strong in operability and capable of being realized in common metallurgical enterprises and steel structure manufacturing plants;
(2) the weather-resistant structural steel with the stabilized rust layer can be quickly and economically formed, the formation time of the stabilized rust layer is within the manufacturing period of the steel structure, additional manufacturing time is not needed, and the manufacturing requirements of structural members such as buildings, towers, ocean platforms and the like are met.
Detailed Description
The present invention will be described in further detail with reference to examples to facilitate the clear understanding of the present invention, but the present invention is not limited thereto.
In order to highlight the performance of the weathering structural steel with stabilized rust layer according to the present invention, 6 examples were prepared according to the requirements of chemical element components, mass percentages and process parameters of the preparation process of the present invention, and 2 comparative examples were simultaneously performed, wherein table 1 shows values of the element components and weight percentages in examples 1 to 6 of the present invention and comparative examples 1 to 2, table 2 shows production process parameters of examples 1 to 6 of the present invention and comparative examples 1 to 2, and table 3 shows performance test results of the steels prepared in examples 1 to 6 of the present invention and the steels prepared in comparative examples 1 to 2.
TABLE 1 chemical composition (wt%) of steel grades of examples of the invention and comparative examples
TABLE 2 heating and rolling process for steel grades of examples and comparative examples of the invention
TABLE 3 mechanical test results of steel grades prepared in examples of the present invention and comparative examples
As can be seen from tables 1-3 above, the steel sheets prepared in examples 1-6 of the present invention had the following physical property levels: the yield strength is 380-445 MPa, the tensile strength is 520-585 MPa, the low-temperature toughness is excellent, and the KV at minus 40 ℃ is2The rust layer stabilization time is 7-15 days, and the stabilization can be completed within the flow time range of the steel structure manufacturing cycle without prolonging the time. While the composition design of comparative examples 1-2 is to improve the corrosion resistance of steel by adding conventional Ni, Cr, Cu and to improve the strength by adding higher Mn, too high Cr and Mn elements are disadvantageous to the toughness of steel. In terms of forming a stabilized rust layer, comparative example 1 could be formed in 7 days with much higher cost than the present invention; in contrast, comparative example 2, which was not treated, the stabilized rust layer was formed for a much longer time than in the examples of the present invention, and even the stabilized rust layer could not be formed.
The embodiment 3 of the invention is the best embodiment, the carbon content and the alloy content are moderate in chemical composition, the composition design can ensure that the steel plate prepared by the invention has good process adaptability, and the produced steel plate has good comprehensive performance. The toughness is matched, the tissue is uniform, and good conditions are created for the subsequent process.
In conclusion, the steel obtained in the embodiments 1 to 6 of the present invention has good physical properties and application properties, is simple in production process, green and environment-friendly, has low cost, and is suitable for the manufacturing requirements of structural members such as buildings, towers, ocean platforms, etc.
The specific embodiments of the present invention are merely illustrative, and not restrictive of the present invention.
Claims (4)
1. A weather-resistant structural steel with a stabilized rust layer is characterized by comprising the following chemical components in percentage by mass: less than or equal to 0.15% of C, less than or equal to 0.20% of Si, 0.80-1.20% of Mn, 0.040-0.070% of P, less than or equal to 0.003% of S, 0.35-0.45% of Ni, 0.22-0.32% of Cu, 0.015-0.030% of Ce, 0.02-0.10% of Sb, and the balance of Fe and inevitable impurity elements.
2. The weathering structural steel with a stabilized rust layer according to claim 1 is characterized by the chemical composition and mass percentages thereof being: 0.08-0.14% of C, less than or equal to 0.20% of Si, 1.00-1.20% of Mn, 0.040-0.050% of P, less than or equal to 0.001% of S, 0.35-0.45% of Ni, 0.22-0.32% of Cu, 0.015-0.030% of Ce, 0.05-0.08% of Sb, and the balance of Fe and inevitable impurity elements.
3. The weathering structural steel with a stabilized rust layer according to claim 1 is characterized by the chemical composition and mass percentages thereof being: 0.10% of C, 0.12% of Si, 1.00% of Mn, 0.055% of P, 0.003% of S, 0.39% of Ni, 0.29% of Cu, 0.026% of Ce, 0.06% of Sb and the balance of Fe and inevitable impurity elements.
4. The method for producing a weathering structural steel with a stabilized rust layer according to claim 1, 2 or 3, characterized in that it comprises the following steps:
(1) molten iron desulfurization, converter smelting and LF refining: adding molten iron into a molten iron tank, carrying out desulfurization treatment on the molten iron, then smelting in a top-bottom combined blown converter, and finally refining in a ladle furnace LF;
(2) and (3) RH furnace vacuum treatment: putting the refined molten iron into an RH furnace for vacuum treatment, adding Sb alloy in the treatment process, and ensuring that the net cycle time is more than or equal to 15min under the ultimate vacuum degree and the content of Sb at the end point meets the target requirement;
(3) protection pouring: the rare earth Re mixture containing Ce element is stably added into the crystallizer, and the rare earth element is utilized to change the inclusion characteristics of steel, thereby improving the toughness and fatigue performance of the steel;
(4) rough rolling and finish rolling: rolling the steel billet in two stages, wherein the initial rolling temperature of rough rolling is 1060-1160 ℃, and the thickness of the intermediate billet is 30-140 mm; the initial rolling temperature of finish rolling is not more than 945 ℃, the rolling thickness specification is 6-64 mm, and the final rolling temperature is 750-840 ℃;
(5) and (3) controlling cooling: controlling the starting cooling temperature to be 720-820 ℃, controlling the cooling speed to be 5-30 ℃/s, and controlling the temperature of red return to be 360-650 ℃;
(6) shot blasting treatment: placing the cooled steel plate in a shot blasting machine at normal temperature for shot blasting to remove the floating rust and the iron scale on the surface of the steel plate, wherein the shot blasting speed is 4-5.5 m/min, and the shot diameter is 0.8-1.8 mm, so that the surface quality of the steel plate reaches the AS 2.5-AS 3.0 level;
(7) and (3) quick rust treatment of the steel plate: flatly paving a steel plate on a track or a cooling bed with a lower water spraying header, then performing periodic watering action, automatically spraying water on the lower surface of the steel plate by using the header, automatically spraying water or manually spraying water on the upper surface of the steel plate for 3 times every 8 hours, keeping dry and wet alternation, and continuously spraying water for more than or equal to 7 days until a uniform yellow rust layer is produced on the surface of the steel plate;
(8) and (3) rust layer stabilization treatment: 5 to 10 mass percent of potassium phosphate solution is uniformly sprayed on the upper surface and the lower surface of the steel plate for stabilization treatment, and if the surface of the steel plate causes local damage in the later processing process, the potassium phosphate solution is adopted for repairing.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114959495A (en) * | 2022-06-25 | 2022-08-30 | 湖南华菱湘潭钢铁有限公司 | Marine climate resistant Q690qE bridge structural steel and production method thereof |
| CN115323142A (en) * | 2022-08-25 | 2022-11-11 | 湖南华菱湘潭钢铁有限公司 | Production method of marine atmospheric corrosion resistant steel plate |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6068712A (en) * | 1998-01-08 | 2000-05-30 | Kawasaki Steel Corporation | Steel products having superior weathering, method of producing the steel products, and method of forming weathering protective rust on steel product surfaces |
| JP2002241972A (en) * | 2001-02-20 | 2002-08-28 | Kawasaki Steel Corp | Surface treated steel having excellent weather resistance |
| JP2002310889A (en) * | 2001-04-09 | 2002-10-23 | Nkk Corp | Rust stabilization degree evaluation method |
| JP2012117145A (en) * | 2010-11-10 | 2012-06-21 | Nippon Sharyo Seizo Kaisha Ltd | Method for forming rust layer on weather resistance steel at early stage |
| CN103459670A (en) * | 2011-03-29 | 2013-12-18 | 杰富意钢铁株式会社 | Steel material with rust layer, exhibiting excellent weather resistance even in high-salt environments |
| CN103952627A (en) * | 2014-05-16 | 2014-07-30 | 武汉钢铁(集团)公司 | High-elongation and low-yield-ratio ferrite weathering-resistant steel and production method thereof |
| CN108754474A (en) * | 2018-06-22 | 2018-11-06 | 燕山大学 | A kind of stabilized treatment fluid of acceleration weathering steel rusty scale |
| CN111593337A (en) * | 2020-05-19 | 2020-08-28 | 北京科技大学 | Environment-friendly weathering steel surface rust layer stabilizing treatment agent and preparation method thereof |
| CN111748734A (en) * | 2020-06-17 | 2020-10-09 | 武汉钢铁有限公司 | 550 MPa-grade weather-resistant steel with stable rust layer for hot-rolled container and production method thereof |
| CN111793394A (en) * | 2020-07-12 | 2020-10-20 | 首钢集团有限公司 | Agent for stabilizing rust layer on surface of weathering resistant steel and method for coating film on surface of weathering resistant steel |
| CN112011798A (en) * | 2020-08-31 | 2020-12-01 | 燕山大学 | Treatment method for accelerating stabilization of rust layer on surface of weathering resistant steel by using electric field |
-
2021
- 2021-08-19 CN CN202110952035.5A patent/CN113621873B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6068712A (en) * | 1998-01-08 | 2000-05-30 | Kawasaki Steel Corporation | Steel products having superior weathering, method of producing the steel products, and method of forming weathering protective rust on steel product surfaces |
| JP2002241972A (en) * | 2001-02-20 | 2002-08-28 | Kawasaki Steel Corp | Surface treated steel having excellent weather resistance |
| JP2002310889A (en) * | 2001-04-09 | 2002-10-23 | Nkk Corp | Rust stabilization degree evaluation method |
| JP2012117145A (en) * | 2010-11-10 | 2012-06-21 | Nippon Sharyo Seizo Kaisha Ltd | Method for forming rust layer on weather resistance steel at early stage |
| CN103459670A (en) * | 2011-03-29 | 2013-12-18 | 杰富意钢铁株式会社 | Steel material with rust layer, exhibiting excellent weather resistance even in high-salt environments |
| CN103952627A (en) * | 2014-05-16 | 2014-07-30 | 武汉钢铁(集团)公司 | High-elongation and low-yield-ratio ferrite weathering-resistant steel and production method thereof |
| CN108754474A (en) * | 2018-06-22 | 2018-11-06 | 燕山大学 | A kind of stabilized treatment fluid of acceleration weathering steel rusty scale |
| CN111593337A (en) * | 2020-05-19 | 2020-08-28 | 北京科技大学 | Environment-friendly weathering steel surface rust layer stabilizing treatment agent and preparation method thereof |
| CN111748734A (en) * | 2020-06-17 | 2020-10-09 | 武汉钢铁有限公司 | 550 MPa-grade weather-resistant steel with stable rust layer for hot-rolled container and production method thereof |
| CN111793394A (en) * | 2020-07-12 | 2020-10-20 | 首钢集团有限公司 | Agent for stabilizing rust layer on surface of weathering resistant steel and method for coating film on surface of weathering resistant steel |
| CN112011798A (en) * | 2020-08-31 | 2020-12-01 | 燕山大学 | Treatment method for accelerating stabilization of rust layer on surface of weathering resistant steel by using electric field |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114959495A (en) * | 2022-06-25 | 2022-08-30 | 湖南华菱湘潭钢铁有限公司 | Marine climate resistant Q690qE bridge structural steel and production method thereof |
| CN115323142A (en) * | 2022-08-25 | 2022-11-11 | 湖南华菱湘潭钢铁有限公司 | Production method of marine atmospheric corrosion resistant steel plate |
| CN115323142B (en) * | 2022-08-25 | 2023-10-24 | 湖南华菱湘潭钢铁有限公司 | Production method of marine atmospheric corrosion resistant steel plate |
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