CN118895454A - A high-strength alloy steel hot-rolled plate and its preparation process - Google Patents

Abstract

The present invention relates to the technical field of alloy materials, specifically to a high-strength alloy steel hot-rolled plate and a preparation process thereof. The present invention obtains an electroslag ingot by vacuum induction melting and electroslag remelting of raw materials; the electroslag ingot is homogenized and forged to obtain a slab; the slab is hot-rolled, annealed, and coated with an anti-corrosion coating to obtain a hot-rolled plate. The anti-corrosion coating includes the following weight components: 40-50 parts of water-based acrylic resin, 12-16 parts of amino resin, 1-5 parts of phosphate compound, 10-15 parts of modified graphene, 5-15 parts of deionized water, 0.1-0.5 parts of dodecylbenzenesulfonic acid, 0.1-0.3 parts of leveling agent, and 0.1-0.2 parts of defoaming agent. The hot-rolled plate prepared by the present invention has excellent strength, and at the same time has corrosion resistance and hydrophobicity, which effectively prolongs its service life.

Description

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

Technical Field

The invention relates to the technical field of alloy materials, in particular to a high-strength alloy steel hot-rolled plate and a preparation process thereof.

Background Art

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 have excellent mechanical properties and wear resistance and are widely used in aerospace, automobile manufacturing, shipbuilding and other fields. The traditional preparation process includes steelmaking, continuous casting, hot rolling and other steps, which require strict control of process parameters and production processes to ensure product quality.

However, the existing technology has the following technical problems: 1. Insufficient strength: The strength of traditional alloy steel hot-rolled plates cannot meet the requirements of certain high-strength applications, such as use under high temperature and high pressure conditions in the aerospace field. 2. Poor corrosion resistance: Traditional alloy steel hot-rolled plates are easily damaged by corrosion in harsh environments, resulting in a shortened service life. 3. Complex preparation process: The traditional preparation process requires multiple steps, a long production cycle, high cost, and high equipment requirements.

Therefore, we propose a high-strength alloy steel hot-rolled plate and a preparation process thereof.

Summary of the invention

The object of the present invention is to provide a high-strength alloy steel hot-rolled plate and a preparation process thereof, so as to solve the problems raised in the above-mentioned background technology.

In order to solve the above technical problems, the present invention provides the following technical solutions:

A preparation process of a high-strength alloy steel hot-rolled plate comprises the following steps:

Step S1: performing vacuum induction melting and electroslag remelting on the raw materials to obtain electroslag ingots;

Step S2: homogenizing and forging the electroslag ingot to obtain a slab;

Step S3: hot rolling and annealing the slab, coating the slab with an anti-corrosion coating, and drying and curing the slab to form an anti-corrosion coating to obtain a hot-rolled plate;

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

The water-based acrylic resin and the amino resin are mixed evenly, and the phosphate compound, the modified graphene, the deionized water, the dodecylbenzene sulfonic acid, the leveling agent and the defoaming agent are added and mixed evenly to obtain the anti-corrosion coating.

Furthermore, in step S1, the raw material includes the following elements in 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%, and the balance is Fe.

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

Furthermore, in step S2, the process conditions for homogenization treatment are: first at 850-900°C, keep warm for 2-4h, then increase to 1100-1130°C, keep warm for 6-10h, and finally increase to 1220-1280°C, keep warm for 24-36h, cool in the furnace to 800-900°C, and then air cool to room temperature.

Furthermore, in step S2, the process conditions of the forging treatment are: initial forging temperature 1200-1250°C, holding time 2-3h, and final forging temperature 900-920°C.

Furthermore, in step S3, the hot rolling process conditions are: heating temperature 1200-1250°C, heat preservation 2-3h, start rolling temperature 1150-1250°C, final rolling temperature 900-930°C, air cooling to room temperature, and cumulative deformation of 70-75%.

Furthermore, in step S3, the process conditions for annealing treatment are: annealing for 1-3 hours under argon protection, and the annealing temperature is 850-900°C.

Furthermore, the anti-corrosion coating includes the following components by weight: 40-50 parts of water-based acrylic resin, 12-16 parts of amino resin, 1-5 parts of phosphate 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 defoaming agent.

Furthermore, the preparation method of the phosphate compound is as follows:

Evenly mix octafluoro-1,6-hexanediol and boron trifluoride etherate, add epichlorohydrin, react at 60-70°C for 6-8h, add tetramethylammonium bromide and sodium hydroxide, mix evenly, react at 35-45°C for 3-5h, filter and distill under reduced pressure to obtain an epoxidized fluorine-containing compound; evenly mix diethyl phosphate, the epoxidized fluorine-containing compound and toluene, add sodium hydroxide, react at 80-100°C for 4-6h, and cool to room temperature to obtain a phosphate compound.

In the above technical scheme, fluorine-containing epoxy compounds are prepared by using octafluoro-1,6-hexanediol and epichlorohydrin as raw materials, and then phosphorus hydroxyl groups in monoethyl phosphate react with epoxy groups in epoxidized fluorine-containing compounds to obtain phosphate ester compounds. This phosphate ester compound not only introduces fluorine-containing groups with hydrophobic properties, improves the hydrophilicity of the metal surface, reduces surface tension, and reduces the adsorption of water molecules, thereby reducing the occurrence of corrosion, but also contains phosphate ions that combine with the metal surface to produce a chelating effect, passivating the metal surface and forming a protective film, effectively preventing further oxidation and corrosion reactions on the metal surface, and extending the service life of the metal material.

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

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

Furthermore, the preparation method of the modified graphene is as follows:

Step (1): 4-(2-thienyl)-2-aminopyrimidine and dodecyl glycidyl ether are mixed evenly, reacted at 40-50° C. for 8-10 hours, and purified and dried to obtain an amino alcohol compound;

Step (2): mixing graphene oxide and anhydrous N,N-dimethylformamide, and ultrasonically dispersing for 1-2 hours to obtain a graphene dispersion; adding isophorone diisocyanate and dibutyltin dilaurate under nitrogen protection, stirring and reacting at 70-80° C. for 6-8 hours, filtering, washing, and drying to obtain isocyanate-based graphene;

Step (3): mixing isocyanate graphene and anhydrous N, N-dimethylformamide, and ultrasonically dispersing for 1-2 hours to obtain an isocyanate graphene dispersion; under nitrogen protection, adding an amino alcohol compound and dibutyltin dilaurate, stirring and reacting at 70-80° C. for 2-4 hours, filtering, washing, and drying to obtain modified graphene.

In the above technical scheme, a hydrophobic long chain is introduced and a hydroxyl group is generated by reacting 4-(2-thienyl)-2-aminopyrimidine and dodecyl glycidyl ether, thereby obtaining an amino alcohol compound with a corrosion inhibition effect. The amino alcohol compound contains O and N heteroatoms in its molecular structure, which can inhibit the oxidation and corrosion reaction of metals. Then, the graphene oxide is modified by isophorone diisocyanate to introduce an isocyanate group to obtain isocyanate graphene. Finally, the amino alcohol compound is grafted on the surface of the isocyanate graphene to improve the hydrophobicity and corrosion resistance of the graphene, so that it has better waterproof and corrosion resistance.

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

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

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

Furthermore, in step (3), the concentration of the isocyanate graphene dispersion is 10 mg/mL.

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

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

Furthermore, the curing temperature is 120-150°C.

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

Compared with the prior art, the present invention has the following beneficial effects:

1. A high-strength alloy steel hot-rolled plate and its preparation process of the present invention, by subjecting the raw materials to vacuum induction melting and electroslag remelting to obtain electroslag ingots, thereby improving the purity and uniformity of the raw materials; subsequently, the electroslag ingots are homogenized and forged to further improve the grain structure and mechanical properties of the alloy, increase the strength and toughness of the material, improve the tensile strength and heat resistance, and provide a good foundation for subsequent hot rolling processing. Finally, after the hot rolling and annealing treatments, the thickness and shape of the plate are adjusted, the surface flatness and finish are improved, the residual stress is eliminated, the plasticity and toughness of the alloy steel are improved, and it has better processing performance and service life; at the same time, the hot rolling and annealing treatments further improve the grain structure of the alloy, improve its strength and wear resistance, and make the alloy steel hot-rolled plate have excellent performance.

2. A high-strength alloy steel hot-rolled plate and a preparation process thereof of the present invention comprises the following steps: uniformly mixing water-based acrylic resin and amino resin, and combining the phosphate compound, modified graphene, deionized water, dodecylbenzene sulfonic acid and a variety of additives to prepare an anti-corrosion coating, which is then applied to the hot-rolled plate. This not only improves the hydrophobicity of the hot-rolled plate, but also gives it excellent corrosion resistance, thereby extending its service life.

DETAILED DESCRIPTION

The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

In this embodiment, the water-based acrylic resin: model J-672, sourced from Qingdao Jinwanli Fine Chemical Co., Ltd.; the amino resin: model 582-2, sourced from Jinan Dahui Chemical Technology Co., Ltd.; the graphene oxide: model DN-20DY, average thickness 1-3nm, diameter 4-7μm, number of layers 2-5 layers, sourced from Zhejiang Zhiti Nano New Materials Co., Ltd.; the leveling agent: model Keying KYC-615; the defoaming agent: model BYK-028.

In the following examples and comparative examples, 1 part is equal to 10 g.

Embodiment 1: A process for preparing a high-strength alloy steel hot-rolled plate, comprising the following processes:

Step S1: subjecting the raw materials to vacuum induction melting (temperature of 1540° C.) and electroslag remelting (melting rate of 4 kg/min) to obtain electroslag ingots;

Step S2: homogenizing the electroslag ingot (first at 850°C, holding for 2h, then increasing to 1100°C, holding for 6h, and finally increasing to 1220°C, holding for 24h, furnace cooling to 800°C, and air cooling to room temperature), forging (initial forging temperature 1200°C, holding time 2h, final forging temperature 900°C), and obtaining a slab;

Step S3: hot rolling the slab (heating temperature 1200°C, heat preservation for 2h, start rolling temperature 1150°C, final rolling temperature 900°C, air cooling to room temperature, cumulative deformation of 70%), annealing (annealing under argon protection for 1h, annealing temperature 850°C), coating the anti-corrosion coating, drying and curing (curing temperature 120°C), forming an anti-corrosion coating with a thickness of 100μm, and obtaining a hot-rolled plate;

In step S1, the raw material includes the following elements in 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%, and the balance is Fe;

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

50 parts of water-based acrylic resin and 12 parts of amino resin are mixed evenly, and 1 part of phosphate compound, 10 parts of modified graphene, 5 parts of deionized water, 0.1 parts of dodecylbenzenesulfonic acid, 0.1 parts of leveling agent and 0.1 parts of defoaming agent are added and mixed evenly to obtain an anticorrosive coating;

The preparation method of the phosphate compound is as follows:

1 part of octafluoro-1,6-hexanediol and 0.1 part of boron trifluoride etherate were mixed evenly, 4 parts of epichlorohydrin were added, and the mixture was reacted at 60°C for 6 hours, 0.02 parts of tetramethylammonium bromide and 0.2 parts of sodium hydroxide were added and mixed evenly, and the mixture was reacted at 35°C for 3 hours, and the mixture was filtered and distilled under reduced pressure to obtain an epoxidized fluorine-containing compound; 1 part of diethyl phosphate, 1 part of the epoxidized fluorine-containing compound and 2 parts of toluene were mixed evenly, 0.01 parts of sodium hydroxide were added, the mixture was reacted at 80°C for 4 hours, and the mixture was cooled to room temperature to obtain a phosphate compound;

The preparation method of modified graphene is as follows:

Step (1): 40 parts of 4-(2-thienyl)-2-aminopyrimidine and 48 parts of dodecyl glycidyl ether were mixed evenly, reacted at 40° C. for 8 hours, and purified and dried to obtain an amino alcohol compound;

Step (2): 10 parts of graphene oxide and anhydrous N, N-dimethylformamide were mixed and ultrasonically dispersed for 1 hour to obtain a 10 mg/mL graphene dispersion; under nitrogen protection, 40 parts of isophorone diisocyanate and 0.1 parts of dibutyltin dilaurate were added, and the mixture was stirred at 70° C. for 6 hours, and after filtering, washing and drying, isocyanate-based graphene was obtained;

Step (3): 10 parts of isocyanate graphene and anhydrous N, N-dimethylformamide are mixed, and ultrasonic dispersion is performed for 1 hour to obtain a 10 mg/mL isocyanate graphene dispersion; under nitrogen protection, 30 parts of an amino alcohol compound and 0.1 parts of dibutyltin dilaurate are added, and the reaction is stirred at 70° C. for 2 hours. After filtering, washing, and drying, modified graphene is obtained.

Embodiment 2: A process for preparing a high-strength alloy steel hot-rolled plate, comprising the following processes:

Step S1: subjecting the raw materials to vacuum induction melting (temperature of 1560° C.) and electroslag remelting (melting rate of 5 kg/min) to obtain electroslag ingots;

Step S2: homogenizing the electroslag ingot (first at 870°C, holding for 3h, then increasing to 1120°C, holding for 8h, and finally increasing to 1260°C, holding for 30h, furnace cooling to 850°C, and air cooling to room temperature), forging (initial forging temperature 1230°C, holding time 2.5h, final forging temperature 910°C), and obtaining a slab;

Step S3: hot rolling the slab (heating temperature 1230°C, heat preservation 2.5h, start rolling temperature 1200°C, final rolling temperature 920°C, air cooling to room temperature, cumulative deformation of 74%), annealing (annealing under argon protection for 2h, annealing temperature 860°C), coating anti-corrosion coating, drying and curing (curing temperature 140°C), forming an anti-corrosion coating with a thickness of 125μm, and obtaining a hot-rolled plate;

In step S1, the raw material includes the following elements in 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%, and the balance is Fe;

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

55 parts of water-based acrylic resin and 14 parts of amino resin were mixed evenly, and 3 parts of phosphate compound, 12 parts of modified graphene, 10 parts of deionized water, 0.3 parts of dodecylbenzenesulfonic acid, 0.2 parts of leveling agent and 0.15 parts of defoaming agent were added and mixed evenly to obtain an anticorrosive coating;

The preparation method of the phosphate compound is as follows:

3 parts of octafluoro-1,6-hexanediol and 0.9 parts of boron trifluoride ether were mixed evenly, 15 parts of epichlorohydrin were added, and the mixture was reacted at 65°C for 7 hours, 0.06 parts of tetramethylammonium bromide and 0.9 parts of sodium hydroxide were added and mixed evenly, and the mixture was reacted at 40°C for 4 hours, and the mixture was filtered and distilled under reduced pressure to obtain an epoxidized fluorine-containing compound; 3 parts of diethyl phosphate, 4.5 parts of the epoxidized fluorine-containing compound and 7.5 parts of toluene were mixed evenly, 0.06 parts of sodium hydroxide were added, the mixture was reacted at 90°C for 5 hours, and the mixture was cooled to room temperature to obtain a phosphate compound;

The preparation method of modified graphene is as follows:

Step (1): 60 parts of 4-(2-thienyl)-2-aminopyrimidine and 78 parts of dodecyl glycidyl ether were mixed evenly, reacted at 45° C. for 9 hours, and purified and dried to obtain an amino alcohol compound;

Step (2): 12 parts of graphene oxide and anhydrous N, N-dimethylformamide were mixed and ultrasonically dispersed for 1.5 hours to obtain a 10 mg/mL graphene dispersion; under nitrogen protection, 60 parts of isophorone diisocyanate and 0.24 parts of dibutyltin dilaurate were added, and the mixture was stirred at 75° C. for 7 hours to obtain isocyanate-based graphene after filtering, washing and drying;

Step (3): 12 parts of isocyanate graphene and anhydrous N, N-dimethylformamide were mixed, and ultrasonic dispersion was performed for 1.5 hours to obtain a 10 mg/mL isocyanate graphene dispersion; under nitrogen protection, 48 parts of an amino alcohol compound and 0.24 parts of dibutyltin dilaurate were added, and the mixture was stirred and reacted at 75° C. for 3 hours. After filtering, washing and drying, modified graphene was obtained.

Embodiment 3: A process for preparing a high-strength alloy steel hot-rolled plate, comprising the following processes:

Step S1: subjecting the raw materials to vacuum induction melting (temperature of 1580° C.) and electroslag remelting (melting rate of 6 kg/min) to obtain electroslag ingots;

Step S2: homogenizing the electroslag ingot (first at 900°C, holding for 4 hours, then increasing to 1130°C, holding for 10 hours, and finally increasing to 1280°C, holding for 36 hours, furnace cooling to 900°C, and air cooling to room temperature), forging (initial forging temperature 1250°C, holding time 3 hours, final forging temperature 920°C), to obtain a slab;

Step S3: hot rolling the slab (heating temperature 1250°C, heat preservation for 3h, start rolling temperature 1250°C, final rolling temperature 930°C, air cooling to room temperature, cumulative deformation of 75%), annealing (annealing for 3h under argon protection, annealing temperature 900°C), coating the anti-corrosion coating, drying and curing (curing temperature 150°C), forming an anti-corrosion coating with a thickness of 150μm, and obtaining a hot-rolled plate;

In step S1, the raw material includes the following elements in 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%, and the balance is Fe;

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

60 parts of water-based acrylic resin and 16 parts of amino resin were mixed evenly, and 5 parts of phosphate compound, 15 parts of modified graphene, 15 parts of deionized water, 0.5 parts of dodecylbenzenesulfonic acid, 0.3 parts of leveling agent and 0.2 parts of defoaming agent were added and mixed evenly to obtain an anticorrosive coating;

The preparation method of the phosphate compound is as follows:

5 parts of octafluoro-1,6-hexanediol and 1.5 parts of boron trifluoride ether were mixed evenly, 30 parts of epichlorohydrin were added, and the mixture was reacted at 70°C for 8 hours, 0.2 parts of tetramethylammonium bromide and 2 parts of sodium hydroxide were added and mixed evenly, and the mixture was reacted at 45°C for 5 hours, and the mixture was filtered and distilled under reduced pressure to obtain an epoxidized fluorine-containing compound; 5 parts of diethyl phosphate, 10 parts of the epoxidized fluorine-containing compound and 15 parts of toluene were mixed evenly, 0.15 parts of sodium hydroxide were added, the mixture was reacted at 100°C for 6 hours, and the mixture was cooled to room temperature to obtain a phosphate compound;

The preparation method of modified graphene is as follows:

Step (1): 75 parts of 4-(2-thienyl)-2-aminopyrimidine and 112.5 parts of dodecyl glycidyl ether were mixed evenly, reacted at 50° C. for 10 hours, and after purification and drying, an amino alcohol compound was obtained;

Step (2): 15 parts of graphene oxide and anhydrous N, N-dimethylformamide were mixed and ultrasonically dispersed for 2 hours to obtain a 10 mg/mL graphene dispersion; under nitrogen protection, 90 parts of isophorone diisocyanate and dibutyltin dilaurate were added, and the mixture was stirred and reacted at 80° C. for 8 hours. After filtering, washing and drying, isocyanate-based graphene was obtained;

Step (3): 15 parts of isocyanate graphene and anhydrous N, N-dimethylformamide are mixed, and ultrasonically dispersed for 2 hours to obtain a 10 mg/mL isocyanate graphene dispersion; under nitrogen protection, 75 parts of an amino alcohol compound and 0.45 parts of dibutyltin dilaurate are added, and the reaction is stirred at 80° C. for 4 hours. After filtering, washing and drying, modified graphene is obtained.

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

Compared with Example 2, Comparative Example 1 did not undergo homogenization or forging, and the other steps were the same as those of Example 2.

Comparative Example 2: The anti-corrosion coating includes the following components by weight: 55 parts of water-based acrylic resin, 14 parts of amino resin, 3 parts of phosphate 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 defoaming agent. Compared with Example 2, Comparative Example 2 replaces the modified graphene with graphene, and the other steps and processes are the same as Example 2.

Comparative Example 3: The anti-corrosion coating includes the following components by weight: 55 parts of water-based acrylic resin, 14 parts of amino resin, 3 parts of phosphate 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 defoaming agent. The other steps and processes are the same as those in Example 2.

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

The preparation method of modified graphene is as follows:

Step (1): 60 parts of 4-(2-thienyl)-2-aminopyrimidine and 78 parts of dodecyl glycidyl ether were mixed evenly, reacted at 45° C. for 9 hours, and purified and dried to obtain an amino alcohol compound;

Step (2): 12 parts of graphene oxide and anhydrous N, N-dimethylformamide were mixed and ultrasonically dispersed for 1.5 hours to obtain a 10 mg/mL graphene dispersion; under nitrogen protection, 60 parts of isophorone diisocyanate and 0.24 parts of dibutyltin dilaurate were added, and the mixture was stirred at 75° C. for 7 hours to obtain isocyanate-based graphene after filtering, washing and drying;

Step (3): 12 parts of isocyanate graphene and anhydrous N, N-dimethylformamide were mixed, and ultrasonic dispersion was performed for 1.5 hours to obtain a 10 mg/mL isocyanate graphene dispersion; under nitrogen protection, 84 parts of an amino alcohol compound and 0.24 parts of dibutyltin dilaurate were added, and the mixture was stirred and reacted at 75° C. for 3 hours. After filtering, washing, and drying, modified graphene was obtained;

Compared with Example 2, the mass ratio of isocyanate graphene to amino alcohol compound in Comparative Example 4 is 1:7; the other steps are the same as those in Example 2.

Experiment: Take the hot-rolled plates obtained in Examples 1-3 and Comparative Examples 1-4, prepare samples, test their properties respectively and record the test results:

According to the standard GB/T 228.1-2021 "Tensile test of metallic materials Part 1: Test method at room temperature", the tensile strength was determined using an electronic universal testing machine with a tensile speed of 1 mm/min; the static contact angle test was performed using a DSA10-MK2 contact angle meter with 3 μL of deionized water; the corrosion resistance was determined according to GB/T 1771-2007 "Determination of resistance of paints and varnishes to neutral salt spray". The experimental steps were as follows: the temperature in the salt spray chamber was 35°C, the test solution was 5wt% NaCl solution, and the exposure time was 1000h.

Test Results

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 Minor corrosion Comparative Example 4 1242 135.9 Generate bubbles

According to the data in the above table, we can clearly draw the following conclusions:

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

2. Compared with Examples 1-3, the products obtained in Comparative Examples 2 and 3 showed a decrease in hydrophobicity and corrosion resistance, which indicates that compared with graphene, the modified graphene prepared by the present invention has excellent hydrophobicity and corrosion resistance, and can better protect hot-rolled plates; at the same time, the performance of the anti-corrosion coating prepared by the present invention is affected by the composition ratio thereof, and by selecting a composition ratio within the said range, the prepared product has better performance.

3. Compared with Examples 1-3, the contact angle and corrosion resistance of the product obtained in Comparative Example 4 are both reduced. 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 said range, the prepared modified graphene has excellent hydrophobicity and corrosion resistance, thereby extending the service life of the hot-rolled plate.

It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process method article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process method article or device.

Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims (9)

1. A process for preparing a high-strength alloy steel hot-rolled plate, characterized in that it comprises the following steps: Step S1: performing vacuum induction melting and electroslag remelting on the raw materials to obtain electroslag ingots; Step S2: homogenizing and forging the electroslag ingot to obtain a slab; Step S3: hot rolling and annealing the slab, coating the slab with an anti-corrosion coating, and drying and curing the slab to form an anti-corrosion coating to obtain a hot-rolled plate; In step S3, the preparation method of the anti-corrosion coating is as follows: The water-based acrylic resin and the amino resin are mixed evenly, and the phosphate compound, the modified graphene, the deionized water, the dodecylbenzene sulfonic acid, the leveling agent and the defoaming agent are added and mixed evenly to obtain the anti-corrosion coating. 2. A process for preparing a high-strength alloy steel hot-rolled plate according to claim 1, characterized in that: in the step S1, the raw materials include the following elements in 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%, and the balance is Fe. 3. A preparation process for a high-strength alloy steel hot-rolled plate according to claim 1, characterized in that: in the step S2, the process conditions for the homogenization treatment are: first at 850-900°C, keep warm for 2-4 hours, then increase to 1100-1130°C, keep warm for 6-10 hours, and finally increase to 1220-1280°C, keep warm for 24-36 hours, furnace cool to 800-900°C, and then air cool to room temperature. 4. The process for preparing a high-strength alloy steel hot-rolled plate according to claim 1 is characterized in that: in the step S2, the process conditions of the forging treatment are: initial forging temperature 1200-1250°C, holding time 2-3h, and final forging temperature 900-920°C. 5. The process for preparing a high-strength alloy steel hot-rolled plate according to claim 1 is characterized in that: in the step S3, the process conditions for hot rolling are: heating temperature 1200-1250°C, insulation 2-3h, starting rolling temperature 1150-1250°C, final rolling temperature 900-930°C, air cooling to room temperature, and cumulative deformation of 70-75%. 6. A preparation process for a high-strength alloy steel hot-rolled plate according to claim 1, characterized in that the anti-corrosion coating comprises the following components by weight: 40-50 parts of water-based acrylic resin, 12-16 parts of amino resin, 1-5 parts of phosphate 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 defoaming agent. 7. The process for preparing a high-strength alloy steel hot-rolled plate according to claim 6, characterized in that the preparation method of the phosphate ester compound is as follows: Evenly mix octafluoro-1,6-hexanediol and boron trifluoride etherate, add epichlorohydrin, react at 60-70°C for 6-8h, add tetramethylammonium bromide and sodium hydroxide, mix evenly, react at 35-45°C for 3-5h, filter and distill under reduced pressure to obtain an epoxidized fluorine-containing compound; evenly mix diethyl phosphate, the epoxidized fluorine-containing compound and toluene, add sodium hydroxide, react at 80-100°C for 4-6h, and cool to room temperature to obtain a phosphate compound. 8. The process for preparing a high-strength alloy steel hot-rolled plate according to claim 6, characterized in that: the preparation method of the modified graphene is as follows: Step (1): 4-(2-thienyl)-2-aminopyrimidine and dodecyl glycidyl ether are mixed evenly, reacted at 40-50° C. for 8-10 hours, and purified and dried to obtain an amino alcohol compound; Step (2): mixing graphene oxide and anhydrous N,N-dimethylformamide, and ultrasonically dispersing for 1-2 hours to obtain a graphene dispersion; adding isophorone diisocyanate and dibutyltin dilaurate under nitrogen protection, stirring and reacting at 70-80° C. for 6-8 hours, filtering, washing, and drying to obtain isocyanate-based graphene; Step (3): mixing isocyanate graphene and anhydrous N, N-dimethylformamide, and ultrasonically dispersing for 1-2 hours to obtain an isocyanate graphene dispersion; under nitrogen protection, adding an amino alcohol compound and dibutyltin dilaurate, stirring and reacting at 70-80° C. for 2-4 hours, filtering, washing, and drying to obtain modified graphene. 9. A high-strength alloy steel hot-rolled plate obtained according to the preparation process according to any one of claims 1 to 8.