A high-strength alloy steel hot-rolled plate and its preparation process

Abstract

This invention relates to the field of alloy materials technology, specifically to a high-strength alloy steel hot-rolled plate and its preparation process. The invention involves vacuum induction melting and electroslag remelting of raw materials to obtain electroslag ingots; homogenizing and forging the electroslag ingots to obtain slabs; hot-rolling and annealing the slabs, followed by coating with an anti-corrosion coating to obtain a hot-rolled plate. The anti-corrosion coating comprises the following components by weight: 40-50 parts water-based acrylic resin, 12-16 parts amino resin, 1-5 parts phosphate ester compound, 10-15 parts modified graphene, 5-15 parts deionized water, 0.1-0.5 parts dodecylbenzenesulfonic acid, 0.1-0.3 parts leveling agent, and 0.1-0.2 parts defoamer. The hot-rolled plate prepared by this invention exhibits excellent strength, corrosion resistance, and hydrophobicity, effectively extending its service life.

Description

Technical Field

[0001] This invention relates to the field of alloy materials technology, specifically to a high-strength alloy steel hot-rolled plate and its preparation process. Background Technology

[0002] With the development of industrialization and modernization, the demand for high-strength alloy steel hot-rolled plates is increasing. High-strength alloy steel hot-rolled plates possess excellent mechanical properties and wear resistance, and are widely used in aerospace, automotive manufacturing, shipbuilding, and other fields. Traditional manufacturing processes include steelmaking, continuous casting, and hot rolling, requiring strict control of process parameters and production processes to ensure product quality.

[0003] However, existing technologies have the following technical problems: 1. Insufficient strength: The strength of traditional hot-rolled alloy steel plates cannot meet the requirements of some high-strength applications, such as those used under high temperature and high pressure conditions in the aerospace field. 2. Poor corrosion resistance: Traditional hot-rolled alloy steel plates are easily damaged by corrosion in harsh environments, leading to a shortened service life. 3. Complex manufacturing process: Traditional manufacturing processes require multiple steps, have long production cycles, high costs, and high equipment requirements.

[0004] Therefore, we propose a high-strength alloy steel hot-rolled plate and its preparation process. Summary of the Invention

[0005] The purpose of this invention is to provide a high-strength alloy steel hot-rolled plate and its preparation process to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] A process for preparing a high-strength alloy steel hot-rolled plate includes the following steps:

[0008] Step S1: The raw materials are subjected to vacuum induction melting and electroslag remelting to obtain electroslag ingots;

[0009] Step S2: The electroslag ingot is homogenized and forged to obtain a slab;

[0010] Step S3: After hot rolling and annealing, the slab is coated with anti-corrosion paint, dried and cured to form an anti-corrosion coating, thus obtaining a hot-rolled plate;

[0011] In step S3, the preparation method of the anti-corrosion coating is as follows:

[0012] A water-based acrylic resin and an amino resin are mixed evenly, and then a phosphate ester compound, modified graphene, deionized water, dodecylbenzene sulfonic acid, leveling agent, and defoamer are added and mixed evenly to obtain an anti-corrosion coating.

[0013] Furthermore, in step S1, the raw materials comprise the following elements by weight percentage: C: 0.15-0.30%, Si: 0.05-0.20%, Mn: 0.4-1.2%, Cr: 3.2-4.0%, Mo: 2.50-3.25%, Ni: 0.3-0.5%, B: 0.001-0.003%, V: 0.3-0.5%, Nb: 0.02-0.03%, Ti: 0.01-0.02%, P≤0.02%, S≤0.01%, N≤0.004%, with the balance being Fe.

[0014] Furthermore, in step S1, the temperature of vacuum induction melting is 1540-1580℃, and the melting rate of electroslag remelting is 4-6 kg / min.

[0015] Furthermore, in step S2, the homogenization process conditions are as follows: first, hold at 850-900℃ for 2-4 hours, then raise to 1100-1130℃ and hold for 6-10 hours, finally raise to 1220-1280℃ and hold for 24-36 hours, then furnace cool to 800-900℃ and air cool to room temperature.

[0016] Furthermore, in step S2, the forging process conditions are: initial forging temperature 1200-1250℃, holding time 2-3h, and final forging temperature 900-920℃.

[0017] Furthermore, in step S3, the hot rolling process conditions are as follows: heating temperature 1200-1250℃, holding temperature 2-3h, initial rolling temperature 1150-1250℃, final rolling temperature 900-930℃, air cooling to room temperature, and cumulative deformation of 70-75%.

[0018] Furthermore, in step S3, the annealing process conditions are as follows: annealing for 1-3 hours under argon protection at an annealing temperature of 850-900℃.

[0019] Furthermore, the anti-corrosion coating comprises the following components by weight: 40-50 parts of waterborne acrylic resin, 12-16 parts of amino resin, 1-5 parts of phosphate ester compound, 10-15 parts of modified graphene, 5-15 parts of deionized water, 0.1-0.5 parts of dodecylbenzene sulfonic acid, 0.1-0.3 parts of leveling agent, and 0.1-0.2 parts of defoamer.

[0020] Furthermore, the preparation method of the phosphate ester compound is as follows:

[0021] Octafluoro-1,6-hexanediol and boron trifluoride diethyl ether were mixed evenly, and epichlorohydrin was added. The mixture was reacted at 60-70℃ for 6-8 hours. Tetramethylammonium bromide and sodium hydroxide were added and mixed evenly. The mixture was reacted at 35-45℃ for 3-5 hours. After filtration and vacuum distillation, an epoxidized fluorinated compound was obtained. Diethyl phosphate, the epoxidized fluorinated compound, and toluene were mixed evenly, and sodium hydroxide was added. The mixture was reacted at 80-100℃ for 4-6 hours. After cooling to room temperature, a phosphate compound was obtained.

[0022] In the above technical solution, a fluorinated epoxy compound is prepared using octafluoro-1,6-hexanediol and epichlorohydrin as raw materials. Then, a ring-opening reaction is conducted between the phosphoric hydroxyl groups in monoethyl phosphate and the epoxy groups in the fluorinated epoxy compound to obtain a phosphate ester compound. This phosphate ester compound not only introduces hydrophobic fluorinated groups, increasing the hydrophilicity of the metal surface, reducing surface tension, and decreasing water molecule adsorption, thereby reducing corrosion, but also contains phosphate ions that chelate with the metal surface, passivating the metal surface and forming a protective film. This effectively prevents further oxidation and corrosion reactions on the metal surface, extending the service life of the metal material.

[0023] Furthermore, the mass ratio of octafluoro-1,6-hexanediol, boron trifluoride ether, epichlorohydrin, tetramethylammonium bromide, and sodium hydroxide is 1:(0.1-0.3):(4-6):(0.02-0.04):(0.2-0.4).

[0024] Furthermore, the mass ratio of diethyl phosphate, epoxidized fluorinated compound, toluene and sodium hydroxide is 1:(1-2):(2-3):(0.01-0.03).

[0025] Furthermore, the modified graphene is prepared as follows:

[0026] Step (1): Mix 4-(2-thienyl)-2-aminopyrimidine and dodecyl glycidyl ether evenly and react at 40-50℃ for 8-10 h. After purification and drying, an amino alcohol compound is obtained.

[0027] Step (2): Mix graphene oxide and anhydrous N,N-dimethylformamide and ultrasonically disperse for 1-2 hours to obtain a graphene dispersion; under nitrogen protection, add isophorone diisocyanate and dibutyltin dilaurate, stir and react at 70-80℃ for 6-8 hours, and after filtration, washing and drying, obtain isocyanate-based graphene.

[0028] Step (3): Mix isocyanate-based graphene and anhydrous N,N-dimethylformamide, and ultrasonically disperse for 1-2 hours to obtain isocyanate-based graphene dispersion; under nitrogen protection, add amino alcohol compound and dibutyltin dilaurate, and stir at 70-80℃ for 2-4 hours. After filtration, washing and drying, modified graphene is obtained.

[0029] In the above technical solution, a hydrophobic long chain is introduced and hydroxyl groups are generated through the reaction of 4-(2-thienyl)-2-aminopyrimidine and dodecyl glycidyl ether, thus obtaining an amino alcohol compound with corrosion inhibition. The molecular structure of this amino alcohol compound contains O and N heteroatoms, which can inhibit the oxidation and corrosion reaction of metals. Next, graphene oxide is modified by isophorone diisocyanate to introduce isocyanate groups, thus obtaining isocyanate-based graphene. Finally, the amino alcohol compound is grafted onto the surface of the isocyanate-based graphene to improve the hydrophobicity and anti-corrosion properties of graphene, giving it better waterproof and corrosion-resistant capabilities.

[0030] Furthermore, in step (1), the mass ratio of 4-(2-thienyl)-2-aminopyrimidine to dodecyl glycidyl ether is 1:(1.2-1.5).

[0031] Furthermore, in step (2), the concentration of the graphene dispersion is 10 mg / mL.

[0032] Furthermore, in step (2), the mass ratio of graphene oxide, isophorone diisocyanate and dibutyltin dilaurate is 1:(4-6):(0.01-0.03).

[0033] Furthermore, in step (3), the concentration of the isocyanate-based graphene dispersion is 10 mg / mL.

[0034] Furthermore, in step (3), the mass ratio of isocyanate-based graphene, amino alcohol compound and dibutyltin dilaurate is 1:(3-5):(0.01-0.03).

[0035] Furthermore, the thickness of the anti-corrosion coating is 100-150 μm.

[0036] Furthermore, the curing temperature is 120-150℃.

[0037] Furthermore, the thickness of the hot-rolled plate is 3-5 mm.

[0038] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0039] 1. This invention discloses a high-strength alloy steel hot-rolled plate and its preparation process. The process involves vacuum induction melting and electroslag remelting of raw materials to obtain electroslag ingots, thereby improving the purity and uniformity of the raw materials. Subsequently, the electroslag ingots undergo homogenization and forging treatments, further improving the grain structure and mechanical properties of the alloy, increasing the material's strength and toughness, and enhancing tensile strength and heat resistance, thus providing a good foundation for subsequent hot rolling. Finally, the slab, after hot rolling and annealing, has its thickness and shape adjusted, improving surface flatness and smoothness, eliminating residual stress, and enhancing the plasticity and toughness of the alloy steel, resulting in better processing performance and service life. Simultaneously, hot rolling and annealing further improve the alloy's grain structure, increasing its strength and wear resistance, giving the hot-rolled alloy steel plate excellent performance characteristics.

[0040] 2. The present invention relates to a high-strength alloy steel hot-rolled plate and its preparation process, which involves uniformly mixing water-based acrylic resin and amino resin, and combining the effects of phosphate ester compound, modified graphene, deionized water, dodecylbenzene sulfonic acid and various additives to prepare an anti-corrosion coating. Applying this coating to the hot-rolled plate not only improves the hydrophobic properties of the hot-rolled plate, but also endows it with excellent corrosion resistance, thereby extending its service life. Detailed Implementation

[0041] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] In this embodiment, the waterborne acrylic resin, model J-672, is sourced from Qingdao Jinwanli Fine Chemical Co., Ltd.; the amino resin, model 582-2, is sourced from Jinan Dahui Chemical Technology Co., Ltd.; the graphene oxide, model DN-20DY, with an average thickness of 1-3nm, a diameter of 4-7μm, and 2-5 layers, is sourced from Zhejiang Zhitai Nanomaterials Co., Ltd.; the leveling agent, model Keying KYC-615; and the defoamer, model BYK-028.

[0043] In the following examples and comparative examples, 1 part equals 10g.

[0044] Example 1: A process for preparing a high-strength alloy steel hot-rolled plate, comprising the following steps:

[0045] Step S1: The raw materials are subjected to vacuum induction melting (temperature 1540℃) and electroslag remelting (melting rate 4kg / min) to obtain electroslag ingots;

[0046] Step S2: The electroslag ingot is subjected to homogenization treatment (first held at 850℃ for 2 hours, then raised to 1100℃ and held for 6 hours, and finally raised to 1220℃ and held for 24 hours, then furnace cooled to 800℃ and air cooled to room temperature), and forging treatment (initial forging temperature 1200℃, holding time 2 hours, final forging temperature 900℃) to obtain a slab;

[0047] Step S3: The slab is hot rolled (heating temperature 1200℃, holding temperature 2h, initial rolling temperature 1150℃, final rolling temperature 900℃, air-cooled to room temperature, cumulative deformation is 70%), annealed (annealed under argon protection for 1h, annealing temperature 850℃), coated with anti-corrosion coating, dried and cured (curing temperature is 120℃) to form an anti-corrosion coating with a thickness of 100μm, and the hot-rolled plate is obtained.

[0048] In step S1, the raw material comprises the following elements by weight percentage: C: 0.15%, Si: 0.05%, Mn: 0.4%, Cr: 3.20%, Mo: 2.50%, Ni: 0.3%, B: 0.001%, V: 0.3%, Nb: 0.02-0.03%, Ti: 0.01-0.02%, P≤0.02%, S≤0.01%, N≤0.004%, with the balance being Fe;

[0049] In step S3, the preparation method of the anti-corrosion coating is as follows:

[0050] Mix 50 parts of water-based acrylic resin and 12 parts of amino resin evenly, then add 1 part of phosphate ester compound, 10 parts of modified graphene, 5 parts of deionized water, 0.1 part of dodecylbenzene sulfonic acid, 0.1 part of leveling agent and 0.1 part of defoamer and mix evenly to obtain an anti-corrosion coating.

[0051] The preparation method of phosphate ester compounds is as follows:

[0052] One part of octafluoro-1,6-hexanediol and 0.1 part of boron trifluoride diethyl ether were mixed evenly, and 4 parts of epichlorohydrin were added. The mixture was reacted at 60°C for 6 hours. Then, 0.02 parts of tetramethylammonium bromide and 0.2 parts of sodium hydroxide were added and mixed evenly. The mixture was reacted at 35°C for 3 hours. After filtration and vacuum distillation, an epoxidized fluorinated compound was obtained. One part of diethyl phosphate, one part of the epoxidized fluorinated compound, and 2 parts of toluene were mixed evenly, and 0.01 parts of sodium hydroxide were added. The mixture was reacted at 80°C for 4 hours. After cooling to room temperature, a phosphate compound was obtained.

[0053] The preparation method of modified graphene is as follows:

[0054] Step (1): Mix 40 parts of 4-(2-thienyl)-2-aminopyrimidine and 48 parts of dodecyl glycidyl ether evenly, react at 40°C for 8 hours, and after purification and drying, obtain an amino alcohol compound;

[0055] Step (2): Take 10 parts of graphene oxide and anhydrous N,N-dimethylformamide, mix them, and ultrasonically disperse them for 1 hour to obtain a 10 mg / mL graphene dispersion; under nitrogen protection, add 40 parts of isophorone diisocyanate and 0.1 parts of dibutyltin dilaurate, stir and react at 70°C for 6 hours, and after filtration, washing and drying, obtain isocyanate-based graphene;

[0056] Step (3): Mix 10 parts of isocyanate-based graphene and anhydrous N,N-dimethylformamide, and ultrasonically disperse for 1 h to obtain a 10 mg / mL isocyanate-based graphene dispersion; under nitrogen protection, add 30 parts of amino alcohol compound and 0.1 parts of dibutyltin dilaurate, stir and react at 70 °C for 2 h, and after filtration, washing and drying, obtain modified graphene.

[0057] Example 2: A process for preparing a high-strength alloy steel hot-rolled plate, comprising the following steps:

[0058] Step S1: The raw materials are subjected to vacuum induction melting (temperature 1560℃) and electroslag remelting (melting rate 5kg / min) to obtain electroslag ingots;

[0059] Step S2: The electroslag ingot is subjected to homogenization treatment (first held at 870℃ for 3 hours, then raised to 1120℃ and held for 8 hours, and finally raised to 1260℃ and held for 30 hours, then furnace cooled to 850℃ and air cooled to room temperature), and forging treatment (initial forging temperature 1230℃, holding time 2.5 hours, final forging temperature 910℃) to obtain a slab;

[0060] Step S3: The slab is hot rolled (heating temperature 1230℃, holding temperature 2.5h, initial rolling temperature 1200℃, final rolling temperature 920℃, air-cooled to room temperature, cumulative deformation is 74%), annealed (annealed under argon protection for 2h, annealing temperature 860℃), coated with anti-corrosion coating, dried and cured (curing temperature is 140℃) to form an anti-corrosion coating with a thickness of 125μm, and the hot-rolled plate is obtained.

[0061] In step S1, the raw material comprises the following elements by weight percentage: C: 0.18%, Si: 0.1%, Mn: 0.8%, Cr: 3.6%, Mo: 3%, Ni: 0.4%, B: 0.002%, V: 0.4%, Nb: 0.025%, Ti: 0.015%, P≤0.02%, S≤0.01%, N≤0.004%, with the balance being Fe;

[0062] In step S3, the preparation method of the anti-corrosion coating is as follows:

[0063] Mix 55 parts of water-based acrylic resin and 14 parts of amino resin evenly, then add 3 parts of phosphate ester compound, 12 parts of modified graphene, 10 parts of deionized water, 0.3 parts of dodecylbenzene sulfonic acid, 0.2 parts of leveling agent and 0.15 parts of defoamer and mix evenly to obtain an anti-corrosion coating.

[0064] The preparation method of phosphate ester compounds is as follows:

[0065] Three parts of octafluoro-1,6-hexanediol and 0.9 parts of boron trifluoride diethyl ether were mixed evenly, and 15 parts of epichlorohydrin were added. The mixture was reacted at 65°C for 7 hours. Then, 0.06 parts of tetramethylammonium bromide and 0.9 parts of sodium hydroxide were added and mixed evenly. The mixture was reacted at 40°C for 4 hours. After filtration and vacuum distillation, an epoxidized fluorinated compound was obtained. Three parts of diethyl phosphate, 4.5 parts of the epoxidized fluorinated compound, and 7.5 parts of toluene were mixed evenly, and 0.06 parts of sodium hydroxide were added. The mixture was reacted at 90°C for 5 hours. After cooling to room temperature, a phosphate compound was obtained.

[0066] The preparation method of modified graphene is as follows:

[0067] Step (1): Mix 60 parts of 4-(2-thienyl)-2-aminopyrimidine and 78 parts of dodecyl glycidyl ether evenly, react at 45°C for 9 hours, and after purification and drying, obtain an amino alcohol compound;

[0068] Step (2): Take 12 parts of graphene oxide and anhydrous N,N-dimethylformamide, mix them, and ultrasonically disperse them for 1.5 h to obtain a 10 mg / mL graphene dispersion; under nitrogen protection, add 60 parts of isophorone diisocyanate and 0.24 parts of dibutyltin dilaurate, stir and react at 75 °C for 7 h, and after filtration, washing and drying, obtain isocyanate-based graphene;

[0069] Step (3): Mix 12 parts of isocyanate-based graphene and anhydrous N,N-dimethylformamide, and ultrasonically disperse for 1.5 h to obtain a 10 mg / mL isocyanate-based graphene dispersion; under nitrogen protection, add 48 parts of amino alcohol compound and 0.24 parts of dibutyltin dilaurate, stir and react at 75 °C for 3 h, and after filtration, washing and drying, obtain modified graphene.

[0070] Example 3: A process for preparing a high-strength alloy steel hot-rolled plate, comprising the following steps:

[0071] Step S1: The raw materials are subjected to vacuum induction melting (temperature 1580℃) and electroslag remelting (melting rate 6kg / min) to obtain electroslag ingots;

[0072] Step S2: The electroslag ingot is subjected to homogenization treatment (first held at 900℃ for 4 hours, then raised to 1130℃ and held for 10 hours, and finally raised to 1280℃ and held for 36 hours, then furnace cooled to 900℃ and air cooled to room temperature) and forging treatment (initial forging temperature 1250℃, holding time 3 hours, final forging temperature 920℃) to obtain a slab;

[0073] Step S3: The slab is hot rolled (heating temperature 1250℃, holding temperature 3h, initial rolling temperature 1250℃, final rolling temperature 930℃, air-cooled to room temperature, cumulative deformation is 75%), annealed (annealed under argon protection for 3h, annealing temperature 900℃), coated with anti-corrosion coating, dried and cured (curing temperature is 150℃) to form an anti-corrosion coating with a thickness of 150μm, and the hot-rolled plate is obtained.

[0074] In step S1, the raw material comprises the following elements by weight percentage: C: 0.30%, Si: 0.20%, Mn: 1.2%, Cr: 4.0%, Mo: 3.25%, Ni: 0.5%, B: 0.003%, V: 0.5%, Nb: 0.03%, Ti: 0.02%, P≤0.02%, S≤0.01%, N≤0.004%, with the balance being Fe;

[0075] In step S3, the preparation method of the anti-corrosion coating is as follows:

[0076] Mix 60 parts of water-based acrylic resin and 16 parts of amino resin evenly, then add 5 parts of phosphate ester compound, 15 parts of modified graphene, 15 parts of deionized water, 0.5 parts of dodecylbenzene sulfonic acid, 0.3 parts of leveling agent and 0.2 parts of defoamer and mix evenly to obtain an anti-corrosion coating.

[0077] The preparation method of phosphate ester compounds is as follows:

[0078] Five parts of octafluoro-1,6-hexanediol and 1.5 parts of boron trifluoride diethyl ether were mixed evenly, and 30 parts of epichlorohydrin were added. The mixture was reacted at 70°C for 8 hours. Then, 0.2 parts of tetramethylammonium bromide and 2 parts of sodium hydroxide were added and mixed evenly. The mixture was reacted at 45°C for 5 hours. After filtration and vacuum distillation, an epoxidized fluorinated compound was obtained. Five parts of diethyl phosphate, 10 parts of the epoxidized fluorinated compound and 15 parts of toluene were mixed evenly, and 0.15 parts of sodium hydroxide were added. The mixture was reacted at 100°C for 6 hours. After cooling to room temperature, a phosphate compound was obtained.

[0079] The preparation method of modified graphene is as follows:

[0080] Step (1): Mix 75 parts of 4-(2-thienyl)-2-aminopyrimidine and 112.5 parts of dodecyl glycidyl ether evenly, react at 50°C for 10 h, and after purification and drying, obtain an amino alcohol compound;

[0081] Step (2): Take 15 parts of graphene oxide and anhydrous N,N-dimethylformamide, mix them, and ultrasonically disperse them for 2 hours to obtain a 10 mg / mL graphene dispersion; under nitrogen protection, add 90 parts of isophorone diisocyanate and dibutyltin dilaurate, stir and react at 80°C for 8 hours, and after filtration, washing and drying, obtain isocyanate-based graphene;

[0082] Step (3): Mix 15 parts of isocyanate-based graphene and anhydrous N,N-dimethylformamide, and ultrasonically disperse for 2 hours to obtain a 10 mg / mL isocyanate-based graphene dispersion; under nitrogen protection, add 75 parts of amino alcohol compound and 0.45 parts of dibutyltin dilaurate, stir and react at 80°C for 4 hours, and after filtration, washing and drying, obtain modified graphene.

[0083] Comparative Example 1: A process for preparing a high-strength alloy steel hot-rolled plate, comprising the following steps:

[0084] Compared with Example 2, Comparative Example 1 did not undergo homogenization or forging treatment, but the other steps were the same as in Example 2.

[0085] Comparative Example 2: The anti-corrosion coating comprises the following components by weight: 55 parts of water-based acrylic resin, 14 parts of amino resin, 3 parts of phosphate ester compound, 12 parts of graphene, 10 parts of deionized water, 0.3 parts of dodecylbenzene sulfonic acid, 0.2 parts of leveling agent, and 0.15 parts of defoamer. Compared with Example 2, Comparative Example 2 replaces modified graphene with graphene, and the other steps and processes are the same as in Example 2.

[0086] Comparative Example 3: The anti-corrosion coating comprises the following components by weight: 55 parts of water-based acrylic resin, 14 parts of amino resin, 3 parts of phosphate ester compound, 1 part of modified graphene, 10 parts of deionized water, 0.3 parts of dodecylbenzene sulfonic acid, 0.2 parts of leveling agent, and 0.15 parts of defoamer. Other steps and processes are the same as in Example 2.

[0087] Comparative Example 4: A process for preparing a high-strength alloy steel hot-rolled plate, comprising the following steps:

[0088] The preparation method of modified graphene is as follows:

[0089] Step (1): Mix 60 parts of 4-(2-thienyl)-2-aminopyrimidine and 78 parts of dodecyl glycidyl ether evenly, react at 45°C for 9 hours, and after purification and drying, obtain an amino alcohol compound;

[0090] Step (2): Take 12 parts of graphene oxide and anhydrous N,N-dimethylformamide, mix them, and ultrasonically disperse them for 1.5 h to obtain a 10 mg / mL graphene dispersion; under nitrogen protection, add 60 parts of isophorone diisocyanate and 0.24 parts of dibutyltin dilaurate, stir and react at 75 °C for 7 h, and after filtration, washing and drying, obtain isocyanate-based graphene;

[0091] Step (3): Mix 12 parts of isocyanate-based graphene and anhydrous N,N-dimethylformamide, and ultrasonically disperse for 1.5 h to obtain a 10 mg / mL isocyanate-based graphene dispersion; under nitrogen protection, add 84 parts of amino alcohol compound and 0.24 parts of dibutyltin dilaurate, stir and react at 75 °C for 3 h, and after filtration, washing and drying, obtain modified graphene;

[0092] Compared to Example 2, the mass ratio of isocyanate-based graphene to amino alcohol compound in Comparative Example 4 was 1:7; other steps were the same as in Example 2.

[0093] Experiment: Hot-rolled plates obtained in Examples 1-3 and Comparative Examples 1-4 were used to prepare samples. Their properties were tested and the test results were recorded.

[0094] According to GB / T 228.1-2021 "Metallic materials - Tensile testing - Part 1: Test method at room temperature", tensile strength was determined using an electronic universal testing machine at a tensile speed of 1 mm / min; static contact angle was tested using a DSA10-MK2 contact angle meter with 3 μL of deionized water; corrosion resistance was determined according to GB / T 1771-2007 "Determination of resistance to neutral salt spray in paints and varnishes", with the following experimental procedures: the temperature inside the salt spray chamber was 35℃, the test solution was 5 wt% NaCl solution, and the exposure time was 1000 h.

[0095] Test Results

[0096] Tensile strength / MPa Contact angle / ° Corrosion resistance Example 1 1249 150.6 No discoloration or rust. Example 2 1257 152.7 No discoloration or rust. Example 3 1250 151.2 No discoloration or rust. Comparative Example 1 875 148.3 No discoloration or rust. Comparative Example 2 1236 95.8 Significant corrosion Comparative Example 3 1220 118.2 Micro corrosion Comparative Example 4 1242 135.9 Bubbles are generated

[0097] Based on the data in the table above, the following conclusions can be clearly drawn:

[0098] 1. Compared with Examples 1-3, the tensile strength of the product obtained in Comparative Example 1 decreased, indicating that the present invention can further improve the grain structure and mechanical properties of the alloy through homogenization treatment and forging treatment, thereby increasing the strength of the alloy steel.

[0099] 2. Compared with Examples 1-3, the products obtained in Comparative Examples 2 and 3 showed a decrease in hydrophobicity and corrosion resistance. This indicates that the modified graphene prepared in this invention has excellent hydrophobicity and corrosion resistance compared with graphene, and can better protect the hot-rolled plate. At the same time, the performance of the anti-corrosion coating prepared in this invention is affected by its component ratio. By selecting the component ratio within the range described above, the prepared product has better performance.

[0100] 3. Compared with Examples 1-3, the contact angle and corrosion resistance of the product obtained in Comparative Example 4 have decreased. It can be seen that the performance of the modified graphene prepared by the present invention is affected by the ratio of each reagent in its preparation process. By selecting the mass ratio within the range, the prepared modified graphene has excellent hydrophobicity and corrosion resistance, thereby extending the service life of hot-rolled plates.

[0101] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process method article or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process method article or apparatus.

[0102] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for preparing high-strength alloy steel hot-rolled plate, characterized in that: Includes the following steps: Step S1: The raw materials are subjected to vacuum induction melting and electroslag remelting to obtain electroslag ingots; Step S2: The electroslag ingot is homogenized and forged to obtain a slab; Step S3: After hot rolling and annealing, the slab is coated with anti-corrosion paint, dried and cured to form an anti-corrosion coating, thus obtaining a hot-rolled plate; In step S3, the preparation method of the anti-corrosion coating is as follows: A water-based acrylic resin and an amino resin are mixed evenly, and then a phosphate ester compound, modified graphene, deionized water, dodecylbenzene sulfonic acid, a leveling agent, and a defoamer are added and mixed evenly to obtain an anti-corrosion coating. The anti-corrosion coating comprises the following components by weight: 40-50 parts water-based acrylic resin, 12-16 parts amino resin, 1-5 parts phosphate ester compound, 10-15 parts modified graphene, 5-15 parts deionized water, 0.1-0.5 parts dodecylbenzene sulfonic acid, 0.1-0.3 parts leveling agent, and 0.1-0.2 parts defoamer. The modified graphene is prepared as follows: Step (1): Mix 4-(2-thienyl)-2-aminopyrimidine and dodecyl glycidyl ether evenly and react at 40-50℃ for 8-10 h. After purification and drying, an amino alcohol compound is obtained. Step (2): Mix graphene oxide and anhydrous N,N-dimethylformamide and ultrasonically disperse for 1-2 hours to obtain a graphene dispersion; under nitrogen protection, add isophorone diisocyanate and dibutyltin dilaurate, stir and react at 70-80℃ for 6-8 hours, and after filtration, washing and drying, obtain isocyanate-based graphene. Step (3): Mix isocyanate-based graphene and anhydrous N,N-dimethylformamide, and ultrasonically disperse for 1-2 hours to obtain isocyanate-based graphene dispersion; under nitrogen protection, add amino alcohol compound and dibutyltin dilaurate, and stir at 70-80℃ for 2-4 hours. After filtration, washing and drying, modified graphene is obtained.

2. The preparation process of a high-strength alloy steel hot-rolled plate according to claim 1, characterized in that: In step S1, the raw materials comprise the following elements by weight percentage: C: 0.15-0.30%, Si: 0.05-0.20%, Mn: 0.4-1.2%, Cr: 3.2-4.0%, Mo: 2.50-3.25%, Ni: 0.3-0.5%, B: 0.001-0.003%, V: 0.3-0.5%, Nb: 0.02-0.03%, Ti: 0.01-0.02%, P≤0.02%, S≤0.01%, N≤0.004%, with the balance being Fe.

3. The preparation process of a high-strength alloy steel hot-rolled plate according to claim 1, characterized in that: In step S2, the homogenization process conditions are as follows: first, hold at 850-900℃ for 2-4 hours, then raise to 1100-1130℃ and hold for 6-10 hours, finally raise to 1220-1280℃ and hold for 24-36 hours, then furnace cool to 800-900℃ and air cool to room temperature.

4. The preparation process of a high-strength alloy steel hot-rolled plate according to claim 1, characterized in that: In step S2, the forging process conditions are: initial forging temperature 1200-1250℃, holding time 2-3h, and final forging temperature 900-920℃.

5. The preparation process of a high-strength alloy steel hot-rolled plate according to claim 1, characterized in that: In step S3, the hot rolling process conditions are as follows: heating temperature 1200-1250℃, holding temperature for 2-3 hours, initial rolling temperature 1150-1250℃, final rolling temperature 900-930℃, air cooling to room temperature, and cumulative deformation of 70-75%.

6. The preparation process of a high-strength alloy steel hot-rolled plate according to claim 1, characterized in that: The preparation method of the phosphate ester compound is as follows: Octafluoro-1,6-hexanediol and boron trifluoride diethyl ether were mixed evenly, and epichlorohydrin was added. The mixture was reacted at 60-70℃ for 6-8 hours. Tetramethylammonium bromide and sodium hydroxide were added and mixed evenly. The mixture was reacted at 35-45℃ for 3-5 hours. After filtration and vacuum distillation, an epoxidized fluorinated compound was obtained. Diethyl phosphate, the epoxidized fluorinated compound, and toluene were mixed evenly, and sodium hydroxide was added. The mixture was reacted at 80-100℃ for 4-6 hours. After cooling to room temperature, a phosphate compound was obtained.

7. A high-strength alloy steel hot-rolled plate prepared by the preparation process according to any one of claims 1-6.