Corrosion-resistant high-temperature steel composite material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of metal coatings, and provides a corrosion-resistant high-temperature steel composite material and a preparation method and application thereof.The preparation method comprises the steps that pure iron, ferromolybdenum alloy, ferrochrome alloy, ferromanganese alloy and ferrosilicon alloy serve as raw materials; the corrosion-resistant high-temperature steel composite material is obtained sequentially through smelting refining, casting forming, quenching and tempering heat treatment, sand blasting roughening, laser cladding, nitriding treatment and micro-arc oxidation treatment. The invention provides a full-process production method of a corrosion-resistant high-temperature steel composite material, which comprises the following steps: carrying out smelting refining, casting molding and quenching and tempering heat treatment on pure iron and an alloy material as raw materials to obtain alloy steel with better mechanical properties; and then the alloy steel is subjected to surface modification treatment by adopting combination of three processes of laser cladding, nitriding treatment and micro-arc oxidation, so that the mechanical property of an alloy steel product is further improved, and the alloy steel is endowed with excellent corrosion resistance and wear resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of metal plating, and relates to a corrosion-resistant high-temperature steel composite material, a preparation method and application thereof. Background Art

[0002] The development of industrial modernization has placed higher and higher requirements on the surface performance of equipment parts, especially in the use environment of high speed, high temperature, heavy load and corrosive medium, the damage of materials often starts from the surface. The existing steel surface generally does not have a coating, but under extreme use conditions such as acid-base environment or high temperature environment, the steel surface will be corroded, its strength will also decrease, and thus lose its original function.

[0003] Steel surface engineering is developed to solve problems such as corrosion, wear, oxidation and fatigue. Steel is treated by surface modification techniques such as surface coating, spraying and plating to change the morphology, chemical composition, organizational structure and stress state of the steel surface in order to obtain the desired surface properties.

[0004] At present, the commonly used surface modification technologies mainly include thermal spraying surface modification technology, plasma surface modification technology and laser surface modification technology. Among them, the thermal spraying process coating has metallurgical defects such as voids and pores, and it is easy to fall off during use, and its application range is narrow. The film layer generated by plasma surface modification technology is thin, the technology is complex, and the cost is expensive. It is not suitable for large-scale surface modification applications such as corrosion-resistant materials. Laser surface cladding technology is to rapidly heat and melt the alloy powder or ceramic powder and the surface of the steel substrate under the action of the laser beam. After the beam is removed, it self-cools to form a surface coating with a very low dilution rate and metallurgically bonded to the substrate material, thereby significantly improving the wear resistance, corrosion resistance, heat resistance, oxidation resistance and electrical properties of the steel surface. It has the characteristics of simple process, controllable coating thickness, and low production cost. It is most commonly used for surface treatment of steel.

[0005] However, increasingly demanding working conditions require that the surface properties of steel are not limited to a single excellent corrosion resistance, wear resistance or high temperature resistance, but require it to have comprehensive properties such as corrosion resistance, wear resistance and high temperature resistance at the same time. The existing surface modification technology is far from meeting this requirement. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a corrosion-resistant high-temperature steel composite material, a preparation method and application thereof. The present invention provides a full-process production method of a corrosion-resistant high-temperature steel composite material, which uses pure iron and alloy materials as raw materials for smelting and refining, casting and tempering heat treatment to obtain an alloy steel with superior mechanical properties; then the alloy steel is surface modified by combining laser cladding, nitriding and micro-arc oxidation processes to further improve the mechanical properties of the alloy steel product and give the alloy steel excellent corrosion resistance and wear resistance.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for preparing a corrosion-resistant high-temperature steel composite material, the preparation method comprising:

[0009] Using pure iron, ferromolybdenum alloy, ferrochrome alloy, ferromanganese alloy and ferrosilicon alloy as raw materials, successively undergoing smelting and refining, casting and tempering heat treatment to obtain alloy steel, and roughening the surface of the alloy steel by sandblasting to form a roughened surface to obtain sandblasted steel;

[0010] Laser cladding is performed on the roughened surface of the alloy steel material, and the laser cladding process includes:

[0011] Aluminum powder, tungsten carbide powder, nickel powder, cubic boron nitride powder, titanium dioxide powder and cerium dioxide powder are mixed and ball-milled to obtain a cladding material; the cladding material is mixed with a binder solution to obtain a paste-like cladding slurry; the cladding slurry is evenly coated on the roughened surface of the sandblasted steel material, and a cladding slurry layer is formed after drying; the sandblasted steel material with the cladding slurry layer formed thereon is placed in a cladding device, argon gas is introduced into the cavity of the cladding device, and the cladding slurry layer is laser clad by a laser in an argon atmosphere, and a cladding layer is formed on the surface of the sandblasted steel material after cooling, so as to obtain a cladding steel material composed of the cladding layer and the sandblasted steel material;

[0012] After the laser cladding is completed, the cladding layer of the cladding steel material is subjected to nitriding treatment and micro-arc oxidation treatment in sequence to obtain the corrosion-resistant high-temperature steel composite material.

[0013] The present invention provides a full-process production method of a corrosion-resistant high-temperature steel composite material, which uses pure iron and alloy materials as raw materials for smelting and refining, casting and tempering heat treatment to obtain an alloy steel with relatively excellent mechanical properties; then the alloy steel is surface-modified by combining three processes of laser cladding, nitriding treatment and micro-arc oxidation to further improve the mechanical properties of the alloy steel product and give the alloy steel excellent corrosion resistance and wear resistance.

[0014] In the heat treatment process of the alloy steel casting of the present invention, firstly, two annealing treatments are carried out to refine the grains, make the structure uniform, eliminate the dendritic structure and the overheated structure, remove the internal stress of the alloy steel casting, and improve the wear resistance of the alloy steel casting; then, a quenching treatment is carried out, and the supercooled austenite is immersed in low-temperature cooling water for rapid cooling during the most unstable period of the supercooled austenite, so as to reduce the internal stress in the alloy steel casting while ensuring the acquisition of martensite, and prevent the alloy steel casting from deformation and cracking.

[0015] The present invention adopts a combination of laser cladding, nitriding and micro-arc oxidation processes to carry out surface modification treatment on the alloy steel. During the laser cladding process, cerium dioxide powder is added to the cladding material used, which has the advantages that the cerium dioxide powder can be evenly dispersed in the cladding liquid metal under the stirring action of the molten pool, and the cerium dioxide powder serves as a heterogeneous nucleation core, which greatly improves the nucleation rate of the liquid metal; at the same time, since the cerium dioxide powder has a large specific surface area, it can effectively hinder the crystal growth after nucleation by adhering to the liquid-solid interface, refine the crystal organization structure of the cladding layer, reduce the large amount of precipitates appearing at the grain boundaries inside the cladding layer organization, is conducive to the release of thermal stress and growth stress, improves the anti-stripping ability of the cladding layer, and enhances the wear resistance of the corrosion-resistant high-temperature steel composite material.

[0016] The present invention performs sandblasting roughening treatment on the surface of the alloy steel before laser cladding, which can not only improve the bonding strength between the cladding layer and the alloy steel, but also improve the wear resistance of the cladding layer. This is because the surface of the alloy steel forms a rough structure after sandblasting roughening treatment. During the laser cladding process, the rough structure on the surface of the alloy steel affects the absorption of laser energy by the cladding material on the surface of the alloy steel. The cladding material presents different melting results due to different absorption of laser energy. As the surface roughness of the alloy steel increases, the laser energy absorbed by the cladding material gradually increases, so that the unmelted cladding material gradually melts and fills in the rough structure on the surface of the alloy steel, thereby improving the mechanical meshing between the cladding layer and the alloy steel, and finally improving the interface bonding strength between the cladding layer and the alloy steel. The improvement of the interface bonding strength allows the interface stress between the alloy steel and the cladding layer to be better released, thereby improving the toughness of the cladding steel, and it is not easy to generate the expansion of microcracks during the wear process, thereby improving the wear resistance of the cladding steel.

[0017] The present invention adopts a pre-set powder processing method in the laser cladding process, that is, the cladding material and the binder solution are first pre-mixed to prepare a cladding slurry, and then the cladding slurry is evenly coated on the surface of the sandblasted steel, and then the cladding slurry layer is laser clad. The pre-set powder cladding method provided by the present invention can make most of the laser energy act on the cladding material, effectively reducing the dilution effect of the sandblasted steel on the cladding layer, so that the cladding material is efficiently utilized in the laser cladding process, and the formed cladding layer has a dense structure and no obvious defects such as cracks and pores, and has a good interface with the sandblasted steel. The intermetallic compound structure and good interface matching in the cladding layer also provide structural conditions for subsequent nitriding treatment; in addition, the cladding layer formed after laser cladding has a higher surface roughness, which will also promote the adsorption and diffusion of more active nitrogen atoms during the nitriding process.

[0018] Due to the "rapid heating and cooling" characteristics of the laser cladding process itself, defects such as uneven microstructure and obvious residual stress may occur in the cladding layer. To this end, the present invention performs nitriding treatment on the cladding steel obtained after laser cladding, so that the grains of the cladding layer after nitriding are refined, the grain boundaries and dislocations increase, providing a driving force for the formation of nitrides, and reducing the standard free energy of nitriding phase formation, so that the cladding layer forms nitrides in the heating stage of nitriding, and the depth of the nitriding layer is increased; during the nitriding process, the activation energy required for nitrogen atoms to diffuse along the grain boundaries is low, and the grain boundaries of the cladding layer provide more diffusion channels for the diffusion of nitrogen atoms, which increases the diffusion rate of nitrogen atoms and has a certain catalytic effect on nitriding, so that the nitriding layer obtained after nitriding treatment has a dense structure, and there are no defects such as cracks and holes inside, which improves the wear resistance and corrosion resistance of the steel composite material.

[0019] Before nitriding treatment, the present invention performs electrochemical deposition treatment on the surface of the cladding steel material to form a composite nickel-plated layer containing nano-alumina particles on the surface of the cladding steel material, and then performs low-temperature nitriding on the surface of the composite nickel-plated layer. During the nitriding treatment process, the thermal decomposition of ammonia is a dehydrogenation process, which includes three steps of adsorption, surface reaction and desorption. The surface reaction and desorption process directly affect the decomposition rate of ammonia, and finally affect the thickness of the nitriding layer. The present invention can significantly improve the decomposition of ammonia by doping nano-alumina particles in the composite nickel-plated layer, increase the concentration of active nitrogen atoms in the nitriding atmosphere, thereby promoting the diffusion and penetration of nitrogen atoms, and improving the comprehensive properties of the nitriding layer. This is because, on the one hand, during the nitriding process, O provided by the nano-alumina particles combines with H generated by the decomposition of ammonia to form OH bonds, consumes H generated in the surface reaction and desorption process, makes the thermal decomposition reaction of ammonia proceed in the positive direction, improves the dehydrogenation ability of ammonia, promotes the decomposition of adsorbed ammonia and produces more active nitrogen atoms, and provides favorable conditions for the formation of metal nitrides, thereby achieving the purpose of promoting nitriding. On the other hand, nano-alumina particles can serve as growth carriers for nickel grains, and nickel grains can be distributed in a rod-like shape depending on the growth of nano-alumina particles, making the composite nickel-plated layer present a loose and porous micro-nanocrystalline structure. At the same time, the formation of OH bonds causes O vacancies to appear in the lattice of some nano-alumina particles. The loose and porous structure combined with the O vacancies in the lattice can provide abundant migration channels for the diffusion of active nitrogen atoms into the cladding steel, thereby promoting the penetration of nitrogen atoms.

[0020] The present invention adopts pulse current to assist electrochemical deposition, and with the addition of nano-alumina particles, a composite nickel-plated layer with better surface morphology and higher hardness can be obtained. At the same time, the addition of nano-alumina particles also promotes the deposition rate of the composite nickel-plated layer. This is because, on the one hand, the nano-alumina particles serve as the growth core of nickel grains in the co-deposition process, affecting the morphology and growth orientation of the nickel grains, thereby improving the nucleation rate of the nickel deposition process; at the same time, the nano-alumina particles can also serve as the growth carrier of the nickel grains, thereby improving the dispersibility of the nickel grains, increasing the number of surface active sites of the composite nickel-plated layer, and finally accelerating the deposition rate of the composite nickel-plated layer; in addition, since the nano-alumina particles are dispersed on the surface and inside of the composite nickel-plated layer during the electrochemical deposition process, the growth of nickel grains is effectively inhibited, thereby refining the grains and playing a role of dispersion strengthening, so that the surface morphology of the composite nickel-plated layer is relatively uniform and dense, which is beneficial to improving the wear resistance of the composite nickel-plated layer. On the other hand, nano-roughening of the surface of the composite nickel-plated layer can be achieved by adding nano-alumina particles, thereby constructing a rough structure surface layer on the surface of the composite nickel-plated layer. Since the rough structure surface layer has a high density of grain boundaries and dislocation defects, it can reduce the diffusion activation energy required for nitrogen atoms and shorten the diffusion path of nitrogen atoms. It can effectively promote the diffusion and chemical reaction of active nitrogen atoms in the subsequent low-temperature nitriding treatment, and will also promote the adsorption of more active nitrogen atoms on the surface of the composite nickel-plated layer during the nitriding process. On the other hand, pulse-assisted chemical deposition improves the co-deposition effect of nickel and nano-alumina particles, so that the nano-alumina particles are evenly distributed on the surface and inside of the composite nickel-plated layer. The evenly dispersed nano-alumina particles can effectively resist the extension of microcracks, so that the deformation resistance of the composite nickel-plated layer is significantly improved; in addition, due to the characteristics of the pulse waveform, the pulse current is in an alternating on-off state, while affecting the alternating transient and steady-state transformation of the interfacial double electric layer. During the interval of the pulse current, the nickel ions in the nickel plating solution diffuse and migrate to the surface of the cladding steel under the action of the concentration difference, thereby replenishing the nickel ions consumed in large quantities on the surface of the cladding steel, reducing the influence of concentration polarization, increasing the deposition rate of nickel ions, reducing the hydrogen evolution reaction time, and ultimately improving the surface morphology of the composite nickel-plated layer, which is beneficial to improving the overall corrosion resistance and wear resistance of the corrosion-resistant high-temperature steel composite material.

[0021] The present invention combines the electrochemical process, the co-deposition process and the double-pulse current process with the characteristics of nano-alumina particles to achieve a synergistic effect, effectively improve the deposition rate and deposition efficiency of nickel ions, and at the same time ensure that the surface morphology of the composite nickel-plated layer formed by deposition is uniform and dense. When the dual-pulse power supply is in the pulse width, the dual-pulse power supply is turned on to the cladding steel, and electrons move from the negative electrode of the power supply to the cathode of the cladding steel, which causes a large number of electrons to accumulate on the cladding steel, and the potential of the cladding steel shifts negatively, thereby generating a large overpotential. At this time, the nano-alumina particles in the nickel plating solution adsorb the nickel ions in the nickel plating solution and thus carry a positive charge. As the dual-pulse power supply is turned on, the nano-alumina particles and nickel ions in the nickel plating solution change from a disordered motion state to an ordered directional motion state moving toward the surface of the cladding steel, and are adsorbed on the surface of the cladding steel to combine with electrons, thereby increasing the content of nano-alumina particles and nickel ions on the surface of the cladding steel, thereby enhancing the dispersion strengthening effect and mechanical strengthening effect of the nano-alumina particles, and the nickel ions adsorbed on the surface of the cladding steel undergo a reduction reaction to precipitate nickel metal. At the same time, the anode nickel plate connected to the positive electrode of the dual pulse power supply undergoes an oxidation reaction, the metallic nickel loses electrons and becomes nickel ions and dissolves in the nickel plating solution, the anions in the nickel plating solution move to the surface of the nickel plate and undergo an oxidation reaction to release electrons on the surface of the nickel plate, and then the electrons move to the positive electrode of the dual pulse power supply, so far, the closed loop is formed and circulated repeatedly until a composite nickel plating layer is formed on the surface of the cladding steel.

[0022] As the nickel ions adsorbed on the surface of the cladding steel undergo electrochemical reactions and are continuously precipitated, the nickel ions near the surface of the cladding steel are rapidly consumed, and the nucleation rate of the nickel grains in the deposited composite nickel plating layer is greater than the growth rate of the nickel grains. This is superimposed on the dispersion strengthening effect of the nano-alumina particles, further refining the nickel grains. When the double-pulse power supply reaches the pulse interval, the current is stopped from being supplied to the cladding steel and the nickel plate, and the directional effect of the current on the nano-alumina particles disappears, but the precipitation reaction of the nickel ions continues. At this time, the nickel ion concentration near the surface of the cladding steel is much lower than that in other areas, thereby forming a nickel ion concentration difference in the nickel plating solution. Under the diffusion effect of the concentration difference, the effect of the high temperature field and the effect of magnetic stirring, the nickel ions in the high nickel ion concentration area quickly move to the surface of the cladding steel to supplement the nickel ions consumed on the surface of the cladding steel. When the new pulse current width arrives, there are enough nickel ions on the surface of the cladding steel to participate in the electrochemical reaction, thereby effectively improving the deposition rate and deposition efficiency of the nickel ions.

[0023] The present invention performs micro-arc oxidation treatment on the obtained composite steel after nitriding treatment. Since the micro-arc oxidation process is mainly used for valve metals such as Ti, Al, Mg and Zr and their alloys, and the base material of the present invention is alloy steel, the present invention uses aluminum powder as the main cladding material before micro-arc oxidation treatment, forms an aluminum-containing cladding layer on the surface of the alloy steel base through a laser cladding process, and then performs micro-arc oxidation treatment on the cladding layer. A layer of aluminum oxide micro-arc oxidation layer that is firmly bonded to the cladding layer and has stable properties can be formed in situ on the surface of the cladding layer, thereby significantly improving the wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite material.

[0024] The micro-arc oxidation layer is composed of an outer porous layer and an inner dense layer. The outer porous layer presents a three-dimensional porous structure, with protrusions around the micropores, and a small amount of microcracks distributed on the three-dimensional porous structure. The microporous structure in the outer porous layer will become a transport channel for the corrosive agent, so that the micro-arc oxidation layer cannot provide long-term protection for the internal matrix material. Therefore, it is necessary to seal the pores of the outer porous layer to improve the corrosion resistance of the corrosion-resistant high-temperature steel composite material. The present invention uses a silane coupling agent as a sealing agent to seal the micro-arc oxidation layer. The sealing mechanism of the silane coupling agent is as follows: first, the Si-OR group of the silane coupling agent is hydrolyzed to form oligomers, and the main product is a "colloidal dispersion". As the hydrolysis / condensation further deepens, the colloidal particles are converted into gels through cross-linking; the main component of the micro-arc oxidation layer is the metal oxide of the cladding layer, which also contains a part of the metal hydroxide. The silanol hydroxyl groups after hydrolysis of siloxane can form covalent bonds with metal hydroxides on the surface of the micro-arc oxidation layer in the form of dehydration condensation, and the micro-arc oxidation layer provides sites for the film formation of siloxane molecules. When the gel is deposited or accumulated near the micropores of the micro-arc oxidation layer, it plays a role in closing the pores, thereby achieving the blocking of the micropores of the micro-arc oxidation layer.

[0025] As a preferred technical solution of the present invention, based on 100 parts by weight of the cladding material, it includes the following components in parts by weight:

[0026]

[0027]

[0028] Among them, the weight parts of aluminum powder can be 50 parts, 51 parts, 52 parts, 53 parts, 54 parts, 55 parts, 56 parts, 57 parts, 58 parts, 59 parts or 60 parts; the weight parts of tungsten carbide powder can be 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts or 30 parts; the weight parts of nickel powder can be 8.0 parts, 8.2 parts, 8.4 parts, 8.6 parts, 8.8 parts, 9.0 parts, 9.2 parts, 9.4 parts, 9.6 parts, 9.8 parts or 10.0 parts; the weight parts of cubic boron nitride powder can be 4.0 parts, 4.5 parts, 5 .0 parts, 5.5 parts, 6.0 parts, 6.5 parts, 7.0 parts, 7.5 parts or 8.0 parts by weight; the weight parts of titanium dioxide powder can be 3.0 parts, 3.1 parts, 3.2 parts, 3.3 parts, 3.4 parts, 3.5 parts, 3.6 parts, 3.7 parts, 3.8 parts, 3.9 parts or 4.0 parts; the weight parts of cerium dioxide powder can be 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1.0 parts, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts or 1.5 parts, but are not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable.

[0029] In some optional examples, the binder solution consists of anhydrous ethanol and polyvinyl alcohol.

[0030] In some optional examples, the mass ratio of the anhydrous ethanol to the polyvinyl alcohol is (10-20):1, for example, it can be 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1 or 20:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0031] In some optional examples, the ratio of the cladding material to the binder solution is 1g:(0.2-0.3)mL, for example, it can be 1g:0.2mL, 1g:0.21mL, 1g:0.22mL, 1g:0.23mL, 1g:0.24mL, 1g:0.25mL, 1g:0.26mL, 1g:0.27mL, 1g:0.28mL, 1g:0.29mL or 1g:0.3mL, but is not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable.

[0032] In some optional examples, the coating thickness of the cladding slurry is 1 to 2 mm, for example, it can be 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm or 2.0 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0033] In some optional examples, the flow rate of argon gas is 8 to 15 L / min, for example, it can be 8.0 L / min, 8.5 L / min, 9.0 L / min, 9.5 L / min, 10.0 L / min, 10.5 L / min, 11.0 L / min, 11.5 L / min, 12.0 L / min, 12.5 L / min, 13.0 L / min, 13.5 L / min, 14.0 L / min, 14.5 L / min or 15.0 L / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0034] In some optional instances, the laser power emitted by the laser is 3 to 4 kW, for example, 3.0 kW, 3.1 kW, 3.2 kW, 3.3 kW, 3.4 kW, 3.5 kW, 3.6 kW, 3.7 kW, 3.8 kW, 3.9 kW or 4.0 kW, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0035] In some optional instances, the diameter of the laser spot emitted by the laser is 3 to 5 mm, for example, it can be 3.0 mm, 3.2 mm, 3.4 mm, 3.6 mm, 3.8 mm, 4.0 mm, 4.2 mm, 4.4 mm, 4.6 mm, 4.8 mm or 5.0 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0036] In some optional instances, the scanning speed of the laser emitted by the laser is 150 to 200 mm / min, for example, it can be 150 mm / min, 155 mm / min, 160 mm / min, 165 mm / min, 170 mm / min, 175 mm / min, 180 mm / min, 185 mm / min, 190 mm / min, 195 mm / min or 200 mm / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0037] As a preferred technical solution of the present invention, the specific steps of the smelting and refining process include:

[0038] Pure iron is put into a smelting furnace and heated to form molten iron. The molten iron is transferred to an LF refining furnace and the temperature of the molten iron is adjusted to the refining temperature. Subsequently, molybdenum-iron alloy, chromium-iron alloy, manganese-iron alloy and silicon-iron alloy are sequentially added to the molten iron, and argon is blown into the bottom of the molten iron for stirring. After the stirring is completed, a first insulation is performed, and an alloy steel liquid is obtained after the first insulation is completed; a desulfurizer and a dephosphorization agent are added to the alloy steel liquid, and argon is blown into the bottom of the alloy steel liquid for stirring. After stirring, a second insulation is performed. After the second insulation is completed, the alloy steel liquid is transferred to a VD vacuum furnace for vacuuming and pressure maintenance, and then argon is blown into the bottom of the alloy steel liquid to obtain refined molten steel.

[0039] In some optional instances, the heating and melting temperature is 1580-1650°C, for example, it can be 1580°C, 1585°C, 1590°C, 1595°C, 1600°C, 1605°C, 1610°C, 1615°C, 1620°C, 1625°C, 1630°C, 1635°C, 1640°C, 1645°C or 1650°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0040] In some optional examples, the holding time for the heating and smelting is 4 to 5 hours, for example, it can be 4.0h, 4.1h, 4.2h, 4.3h, 4.4h, 4.5h, 4.6h, 4.7h, 4.8h, 4.9h or 5.0h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0041] In some optional examples, the refining temperature is 1650-1750°C, for example, it can be 1650°C, 1660°C, 1670°C, 1680°C, 1690°C, 1700°C, 1710°C, 1720°C, 1730°C, 1740°C or 1750°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0042] In some optional examples, the flow rate of argon introduced into the refined steel liquid while adding molybdenum-iron alloy, chromium-iron alloy, manganese-iron alloy and silicon-iron alloy is 300-400 L / min, for example, it can be 300 L / min, 310 L / min, 320 L / min, 330 L / min, 340 L / min, 350 L / min, 360 L / min, 370 L / min, 380 L / min, 390 L / min or 400 L / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0043] In some optional examples, the time for introducing argon into the refined steel liquid while adding molybdenum-iron alloy, chromium-iron alloy, manganese-iron alloy and silicon-iron alloy is 30 to 40 minutes, for example, it can be 30 minutes, 31 minutes, 32 minutes, 33 minutes, 34 minutes, 35 minutes, 36 minutes, 37 minutes, 38 minutes, 39 minutes or 40 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0044] In some optional examples, the first insulation time is 10 to 20 minutes, for example, it can be 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes, 16 minutes, 17 minutes, 18 minutes, 19 minutes or 20 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0045] In some optional examples, the desulfurizer is composed of lime, fluorite powder and aluminum powder, wherein 8-10 kg of lime, 1-2 kg of fluorite powder and 0.5-1 kg of aluminum powder are added to each ton of alloy steel liquid, the amount of lime added can be 8.0 kg, 8.2 kg, 8.4 kg, 8.6 kg, 8.8 kg, 9.0 kg, 9.2 kg, 9.4 kg, 9.6 kg, 9.8 kg or 10.0 kg, and the amount of fluorite powder added can be 1.0 kg, 1.1 kg The amount of aluminum powder added can be 0.5kg, 0.55kg, 0.6kg, 0.65kg, 0.7kg, 0.75kg, 0.8kg, 0.85kg, 0.9kg, 0.95kg or 1kg, but is not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable.

[0046] In some optional examples, the dephosphorization agent consists of lime and bauxite, wherein 7-9 kg of lime and 1.5-2.5 kg of bauxite are added to each ton of alloy steel liquid, the amount of lime added can be 7.0 kg, 7.2 kg, 7.4 kg, 7.6 kg, 7.8 kg, 8.0 kg, 8.2 kg, 8.4 kg, 8.6 kg, 8.8 kg or 9.0 kg, and the amount of bauxite added can be 1.5 kg, 1.6 kg, 1.7 kg, 1.8 kg, 1.9 kg, 2.0 kg, 2.1 kg, 2.2 kg, 2.3 kg, 2.4 kg or 2.5 kg, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0047] In some optional examples, the flow rate of argon gas introduced into the molten steel while adding the desulfurizer and dephosphorization agent is 500-600 L / min, for example, it can be 500 L / min, 510 L / min, 520 L / min, 530 L / min, 540 L / min, 550 L / min, 560 L / min, 570 L / min, 580 L / min, 590 L / min or 600 L / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0048] In some optional examples, the time for introducing argon into the molten steel while adding the desulfurizer and dephosphorization agent is 3 to 5 minutes, for example, it can be 3.0 minutes, 3.2 minutes, 3.4 minutes, 3.6 minutes, 3.8 minutes, 4.0 minutes, 4.2 minutes, 4.4 minutes, 4.6 minutes, 4.8 minutes or 5.0 minutes, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0049] In some optional instances, the second insulation time is 10 to 20 minutes, for example, it can be 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes, 16 minutes, 17 minutes, 18 minutes, 19 minutes or 20 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0050] In some optional instances, the vacuum degree of the alloy steel liquid in the VD vacuum furnace is 50-60Pa, for example, it can be 50Pa, 51Pa, 52Pa, 53Pa, 54Pa, 55Pa, 56Pa, 57Pa, 58Pa, 59Pa or 60Pa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0051] In some optional examples, the pressure holding time of the alloy steel liquid in the VD vacuum furnace is 20 to 30 minutes, for example, it can be 20 minutes, 21 minutes, 22 minutes, 23 minutes, 24 minutes, 25 minutes, 26 minutes, 27 minutes, 28 minutes, 29 minutes or 30 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0052] In some optional examples, the flow rate of argon gas introduced into the alloy steel liquid after vacuuming is 3 to 5 L / min, for example, it can be 3.0 L / min, 3.2 L / min, 3.4 L / min, 3.6 L / min, 3.8 L / min, 4.0 L / min, 4.2 L / min, 4.4 L / min, 4.6 L / min, 4.8 L / min or 5.0 L / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0053] In some optional examples, the time for introducing argon gas into the alloy steel liquid after vacuuming is 10 to 20 minutes, for example, it can be 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes, 16 minutes, 17 minutes, 18 minutes, 19 minutes or 20 minutes, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0054] In some optional examples, based on the mass fraction of the refined steel liquid being 100wt%, the mass fraction of each element in the refined steel liquid is controlled within the following range:

[0055] Carbon 0.01-0.02wt%, molybdenum 2.0-2.5wt%, chromium 16-17wt%, manganese 1.2-1.5wt%, silicon 0.5-0.6wt%, sulfur 0.001-0.003wt% and phosphorus 0.01-0.05wt%, the balance is iron; wherein the mass fraction of carbon can be 0.01wt%, 0.011wt%, 0.012wt%, 0.013wt%, 0.014wt%, 0.015wt%, 0.016wt%, 0.017wt%, 0.018wt%, 0.019wt% or 0.02wt%, and the mass fraction of molybdenum can be The mass fraction of chromium can be 2.0wt%, 2.05wt%, 2.1wt%, 2.15wt%, 2.2wt%, 2.25wt%, 2.3wt%, 2.35wt%, 2.4wt%, 2.45wt% or 2.5wt%, the mass fraction of chromium can be 16wt%, 16.1wt%, 16.2wt%, 16.3wt%, 16.4wt%, 16.5wt%, 16.6wt%, 16.7wt%, 16.8wt%, 16.9wt% or 17wt%, and the mass fraction of manganese can be 1.2wt%, 1.22wt%, 1.24wt%, 1.2 The mass fraction of silicon may be 0.5wt%, 0.51wt%, 0.52wt%, 0.53wt%, 0.54wt%, 0.55wt%, 0.56wt%, 0.57wt%, 0.58wt%, 0.59wt% or 0.6wt%, and the mass fraction of sulfur may be 0.001wt%, 0.001wt%, 0.002wt%, 0.003wt%, 0.004wt%, 0.005wt%, 0.006wt%, 0.008wt%, 0.009wt%, 0.10wt%, 0.11wt%, 0.12wt%, 0.13wt%, 0.14wt%, 0.15wt%, 0.16wt%, 0.17wt%, 0.18wt%, 0.19wt%, 0.20wt%, 0.21wt%, 0.22wt%, 0.23wt%, 0.24wt%, 0.25wt%, 0.26wt%, 0.27wt%, 0.28wt%, .0012wt%, 0.0014wt%, 0.0016wt%, 0.0018wt%, 0.002wt%, 0.0022wt%, 0.0024wt%, 0.0026wt%, 0.0028wt% or 0.03wt% and the mass fraction of phosphorus can be 0.01wt%, 0.015wt%, 0.02wt%, 0.025wt%, 0.03wt%, 0.035wt%, 0.04wt%, 0.045wt% or 0.05wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable.

[0056] As a preferred technical solution of the present invention, the specific steps of the casting process include:

[0057] The refined molten steel obtained by smelting and refining is injected into a casting device for vacuum casting. The casting device includes a vacuum chamber, an ingot mold and a tundish. The ingot mold is located inside the vacuum chamber, the tundish is located on the top of the vacuum chamber, and a liquid outlet is provided at the bottom of the tundish. The tundish is connected to the ingot mold through the liquid outlet, and the liquid outlet is externally connected to an argon gas source. The temperature of the refined molten steel is adjusted to the casting temperature and then injected into the tundish. The argon gas source introduces argon gas into the liquid outlet. When the refined molten steel flows through the liquid outlet, it is mixed with argon gas and then flows into the ingot mold. After the refined molten steel is completely injected into the ingot mold, it is naturally cooled to room temperature, and an alloy steel casting is obtained after demoulding.

[0058] In some optional instances, the casting temperature of the refined steel liquid is 1520-1530°C, for example, it can be 1520°C, 1521°C, 1522°C, 1523°C, 1524°C, 1525°C, 1526°C, 1527°C, 1528°C, 1529°C or 1530°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0059] In some optional examples, before casting the refined molten steel, the ingot mold is preheated to 200-250°C, for example, 200°C, 205°C, 210°C, 215°C, 220°C, 225°C, 230°C, 235°C, 240°C, 245°C or 250°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0060] In some optional examples, the speed of injecting the refined molten steel into the tundish is 3 to 8 t / min, for example, it can be 3.0 t / min, 3.5 t / min, 4.0 t / min, 4.5 t / min, 5.0 t / min, 5.5 t / min, 6.0 t / min, 6.5 t / min, 7.0 t / min, 7.5 t / min or 8.0 t / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0061] In some optional examples, the flow rate of the argon gas entering the liquid outlet is 5 to 8 L / min, for example, it can be 3.0 L / min, 3.5 L / min, 4.0 L / min, 4.5 L / min, 5.0 L / min, 5.5 L / min, 6.0 L / min, 6.5 L / min, 7.0 L / min, 7.5 L / min or 8.0 L / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0062] As a preferred technical solution of the present invention, the specific steps of the quenching and tempering heat treatment process include:

[0063] The alloy steel casting obtained by casting is heated to a first annealing temperature, kept warm at the first annealing temperature, and completed a primary annealing treatment after the insulation is completed; then, the alloy steel casting after the primary annealing treatment is furnace cooled to a second annealing temperature, kept warm at the second annealing temperature, and after the insulation is completed, the alloy steel casting is taken out of the furnace and air-cooled to room temperature to complete a secondary annealing treatment; the alloy steel casting after the secondary annealing treatment is heated to a quenching temperature, kept warm at the quenching temperature, and after the insulation is completed, the alloy steel casting is taken out of the furnace and immediately immersed in cooling water for rapid cooling to complete the quenching treatment, and an alloy steel material is obtained after the quenching treatment is completed.

[0064] In some optional examples, the alloy steel casting is heated to a first annealing temperature at a heating rate of 80 to 100°C / h, for example, 80°C / h, 82°C / h, 84°C / h, 86°C / h, 88°C / h, 90°C / h, 92°C / h, 94°C / h, 96°C / h, 98°C / h or 100°C / h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0065] In some optional instances, the first annealing temperature is 900-950°C, for example, it may be 900°C, 905°C, 910°C, 915°C, 920°C, 925°C, 930°C, 935°C, 940°C, 945°C or 950°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0066] In some optional examples, the first annealing temperature is kept for 2 to 3 hours, for example, 2.0 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours or 3.0 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0067] In some optional instances, the second annealing temperature is 680-700°C, for example, it can be 680°C, 682°C, 684°C, 686°C, 688°C, 690°C, 692°C, 694°C, 696°C, 698°C or 700°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0068] In some optional examples, the second annealing temperature is kept for 4 to 5 hours, for example, 4.0 hours, 4.1 hours, 4.2 hours, 4.3 hours, 4.4 hours, 4.5 hours, 4.6 hours, 4.7 hours, 4.8 hours, 4.9 hours or 5.0 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0069] In some optional examples, the alloy steel casting after the secondary annealing treatment is heated to the quenching temperature at a heating rate of 60 to 70°C / h, for example, it can be 60°C / h, 61°C / h, 62°C / h, 63°C / h, 64°C / h, 65°C / h, 66°C / h, 67°C / h, 68°C / h, 69°C / h or 70°C / h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0070] In some optional instances, the quenching temperature is 850-900°C, for example, it can be 850°C, 855°C, 860°C, 865°C, 870°C, 875°C, 880°C, 885°C, 890°C, 895°C or 900°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0071] In some optional examples, the quenching temperature is kept for 50 to 60 minutes, for example, 50 minutes, 51 minutes, 52 minutes, 53 minutes, 54 minutes, 55 minutes, 56 minutes, 57 minutes, 58 minutes, 59 minutes or 60 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0072] In some optional examples, the temperature of the cooling water is 10-30°C, for example, it can be 10°C, 12°C, 14°C, 16°C, 18°C, 20°C, 22°C, 24°C, 26°C, 28°C or 30°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0073] In some optional examples, the cooling rate of the alloy steel casting in the cooling water is 150-160°C / h, for example, it can be 150°C / h, 151°C / h, 152°C / h, 153°C / h, 154°C / h, 155°C / h, 156°C / h, 157°C / h, 158°C / h, 159°C / h or 160°C / h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0074] In some optional instances, the immersion time of the alloy steel casting in the cooling water is 60 to 90 min, for example, it can be 60 min, 62 min, 64 min, 66 min, 68 min, 70 min, 72 min, 74 min, 76 min, 78 min, 80 min, 82 min, 84 min, 86 min, 88 min or 90 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0075] As a preferred technical solution of the present invention, the specific steps of the sandblasting roughening process include:

[0076] The surface of the alloy steel obtained by the quenching and tempering heat treatment is polished with fine sandpaper to remove the oxide scale on the surface of the alloy steel; the polished surface of the alloy steel is rinsed with clean water and dried, and the dried alloy steel is immersed in a pickling solution. After the immersion, the alloy steel is taken out and immersed in an ultrasonic device filled with clean water, and the alloy steel is ultrasonically cleaned and dried; the surface of the dried alloy steel is sandblasted, and the alloy steel is cleaned and dried after the sandblasting is completed; the alloy steel is immersed in a passivation solution for surface passivation treatment, and the alloy steel is cleaned and dried after the passivation is completed to obtain a sandblasted steel.

[0077] In some optional examples, the mesh number of the fine sandpaper is 400-500 mesh, for example, it can be 420 mesh, 430 mesh, 440 mesh, 450 mesh, 460 mesh, 470 mesh, 480 mesh, 490 mesh or 500 mesh, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0078] In some optional examples, the pickling solution is a nitric acid solution, a sulfuric acid solution or a hydrochloric acid solution.

[0079] In some optional examples, the mass fraction of the pickling solution is 40-50wt%, for example, it can be 40wt%, 41wt%, 42wt%, 43wt%, 44wt%, 45wt%, 46wt%, 47wt%, 48wt%, 49wt% or 50wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0080] In some optional examples, the temperature of the pickling solution is 40-50°C, for example, 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C or 50°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0081] In some optional examples, the immersion time of the alloy steel in the pickling solution is 30 to 40 minutes, for example, it can be 30 minutes, 31 minutes, 32 minutes, 33 minutes, 34 minutes, 35 minutes, 36 minutes, 37 minutes, 38 minutes, 39 minutes or 40 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0082] In some optional instances, the ultrasonic power of the ultrasonic device is 800-1000W, for example, it can be 800W, 820W, 840W, 860W, 880W, 900W, 920W, 940W, 960W, 980W or 1000W, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0083] In some optional instances, the ultrasonic cleaning time is 20 to 30 minutes, for example, it can be 20 minutes, 21 minutes, 22 minutes, 23 minutes, 24 minutes, 25 minutes, 26 minutes, 27 minutes, 28 minutes, 29 minutes or 30 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0084] In some optional examples, before the sandblasting, the alloy steel is preheated to 50-60°C, for example, 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C or 60°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0085] In some optional examples, the blasting medium used in the sandblasting process is white corundum.

[0086] In some optional examples, the particle size of the sandblasting medium used in the sandblasting treatment is 1 to 3 mm, for example, it can be 1.0 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2.0 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm or 3.0 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0087] In some optional instances, the blasting pressure of the sandblasting treatment is 0.5-0.6 MPa, for example, it can be 0.5 MPa, 0.51 MPa, 0.52 MPa, 0.53 MPa, 0.54 MPa, 0.55 MPa, 0.56 MPa, 0.57 MPa, 0.58 MPa, 0.59 MPa or 0.6 MPa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0088] In some optional examples, the blasting distance between the nozzle and the surface of the alloy steel during the sandblasting process is 100-150 mm, for example, it can be 100 mm, 105 mm, 110 mm, 115 mm, 120 mm, 125 mm, 130 mm, 135 mm, 140 mm, 145 mm or 150 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0089] In some optional examples, the angle between the nozzle axis and the surface of the alloy steel during the sandblasting process is 60-70°, for example, it can be 60°, 61°, 62°, 63°, 64°, 65°, 66°, 67°, 68°, 69° or 70°, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0090] In some optional instances, the sandblasting time is 3 to 8 minutes, for example, it can be 3.0 minutes, 3.5 minutes, 4.0 minutes, 4.5 minutes, 5.0 minutes, 5.5 minutes, 6.0 minutes, 6.5 minutes, 7.0 minutes, 7.5 minutes or 8.0 minutes, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0091] The alloy steel surface will form different surface roughness after different sandblasting time, and the surface roughness will directly affect the laser absorption rate of the sandblasted steel surface. When the laser is irradiated on the sandblasted steel surface, the change of the surface roughness of the sandblasted steel makes the cladding material present different fusion degrees during the laser cladding process. When the sandblasting time is within the range of 3 to 8 minutes, during the laser cladding process, the cladding material is fully melted by the laser energy, and the grain structure in the cladding layer is better grown and refined. The roughness of the final cladding layer is moderate and the grain size distribution is uniform, which is not only conducive to the interface bonding between the subsequent cladding layer and the sandblasted steel surface, but also improves the resistance of the cladding layer to plastic deformation during friction and wear, and improves the overall wear resistance of the corrosion-resistant high-temperature steel composite material.

[0092] When the sandblasting time is short, the grain size in the cladding layer is relatively small, the grain structure is too fine, and the roughness is too low, which cannot form a good interface with the cladding layer during the subsequent laser cladding process, and will also affect the adsorption of active nitrogen atoms during the nitriding process. When the sandblasting time exceeds 8 minutes, the surface roughness of the sandblasted steel is too large, resulting in an increase in the high heat source input and the corresponding temperature gradient during the later cladding process, an increase in the absorption of laser by the sandblasted steel, and an overmelting of the cladding material due to the absorption of too much laser energy, which slows down the crystallization rate of the grains in the molten pool. Therefore, the crystal structure in the obtained cladding layer is coarse and uneven, which affects the strength and density of the cladding layer and reduces the wear resistance of the cladding layer.

[0093] In some optional examples, the passivation solution consists of citric acid, ethylenediaminetetraacetic acid and deionized water.

[0094] In some optional examples, the mass fraction of citric acid in the passivation solution is 15 to 25wt%, for example, it can be 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, 21wt%, 22wt%, 23wt%, 24wt% or 25wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0095] In some optional examples, the mass fraction of ethylenediaminetetraacetic acid in the passivation solution is 0.5-1.5wt%, for example, it can be 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1.0wt%, 1.1wt%, 1.2wt%, 1.3wt%, 1.4wt% or 1.5wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0096] In some optional examples, the temperature of the passivation solution is 60-70°C, for example, it can be 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C or 70°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0097] In some optional examples, the immersion time of the alloy steel in the passivation solution is 20 to 30 minutes, for example, it can be 20 minutes, 21 minutes, 22 minutes, 23 minutes, 24 minutes, 25 minutes, 26 minutes, 27 minutes, 28 minutes, 29 minutes or 30 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0098] As a preferred technical solution of the present invention, the nitriding process specifically includes the following steps:

[0099] Nickel sulfate, sodium citrate, sodium acetate, thiourea, potassium iodide, succinic acid, sodium dodecyl sulfate, sodium hypophosphite, alumina sol and deionized water are mixed to obtain a nickel plating solution, the nickel plating solution is poured into a constant temperature water bath, and the nickel plating solution is heated and stirred; the clad steel and the nickel plate obtained by laser cladding are immersed in the nickel plating solution and are electrically connected to the negative electrode and the positive electrode of a double pulse power supply respectively, the clad steel is electrochemically deposited to form a composite nickel coating on the surface of the clad steel to obtain nickel-plated steel; the nickel-plated steel is placed in a heat treatment device, ammonia is introduced into the cavity of the heat treatment device, the nickel-plated steel is heated to a nitriding temperature and kept warm to perform a nitriding treatment to obtain a composite steel.

[0100] In some optional instances, the concentration of nickel sulfate in the nickel plating solution is 25-35 g / L, for example, it can be 25 g / L, 26 g / L, 27 g / L, 28 g / L, 29 g / L, 30 g / L, 31 g / L, 32 g / L, 33 g / L, 34 g / L or 35 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0101] In some optional examples, the concentration of sodium citrate in the nickel plating solution is 15-25 g / L, for example, it can be 15 g / L, 16 g / L, 17 g / L, 18 g / L, 19 g / L, 20 g / L, 21 g / L, 22 g / L, 23 g / L, 24 g / L or 25 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0102] In some optional examples, the concentration of sodium acetate in the nickel plating solution is 15-25 g / L, for example, it can be 15 g / L, 16 g / L, 17 g / L, 18 g / L, 19 g / L, 20 g / L, 21 g / L, 22 g / L, 23 g / L, 24 g / L or 25 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0103] In some optional examples, the concentration of thiourea in the nickel plating solution is 0.1-0.5 mg / L, for example, it can be 0.1 mg / L, 0.15 mg / L, 0.2 mg / L, 0.25 mg / L, 0.3 mg / L, 0.35 mg / L, 0.4 mg / L, 0.45 mg / L or 0.5 mg / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0104] In some optional examples, the concentration of potassium iodide in the nickel plating solution is 1 to 5 mg / L, for example, it can be 1.0 mg / L, 1.5 mg / L, 2.0 mg / L, 2.5 mg / L, 3.0 mg / L, 3.5 mg / L, 4.0 mg / L, 4.5 mg / L or 5.0 mg / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0105] In some optional examples, the concentration of succinic acid in the nickel plating solution is 15-25 g / L, for example, it can be 15 g / L, 16 g / L, 17 g / L, 18 g / L, 19 g / L, 20 g / L, 21 g / L, 22 g / L, 23 g / L, 24 g / L or 25 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0106] In some optional examples, the concentration of sodium dodecyl sulfate in the nickel plating solution is 0.2-0.6 g / L, for example, it can be 0.2 g / L, 0.25 g / L, 0.3 g / L, 0.35 g / L, 0.4 g / L, 0.45 g / L, 0.5 g / L, 0.55 g / L or 0.6 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0107] In some optional examples, the concentration of sodium hypophosphite in the nickel plating solution is 20-30 g / L, for example, it can be 20 g / L, 21 g / L, 22 g / L, 23 g / L, 24 g / L, 25 g / L, 26 g / L, 27 g / L, 28 g / L, 29 g / L or 30 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0108] In some optional examples, the concentration of alumina sol in the nickel plating solution is 15-25 mL / L, for example, it can be 15 mL / L, 16 mL / L, 17 mL / L, 18 mL / L, 19 mL / L, 20 mL / L, 21 mL / L, 22 mL / L, 23 mL / L, 24 mL / L or 25 mL / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0109] The present invention specifically limits the concentration of alumina sol in the nickel plating solution to 15-25 mL / L. As the concentration of alumina sol increases, the thickness of the nitriding layer formed after nitriding treatment shows a trend of first increasing and then decreasing. When the concentration of alumina sol is within the range of 15-25 mL / L, the ammonia decomposition rate on the surface of the nickel-plated steel is high and the nitride formed is less. Therefore, the active nitrogen atoms produced by the decomposition of ammonia almost all penetrate into the interior of the nickel-plated steel, thereby increasing the thickness of the nitriding layer. When the concentration of alumina sol exceeds 25 mL / L, the higher concentration can improve the dispersibility of nickel ions, but nano-alumina particles are also more likely to regularly agglomerate and accumulate on the surface of the composite nickel-plating layer, making the surface roughness of the composite nickel-plating layer too large, which is not conducive to improving the wear resistance of the corrosion-resistant high-temperature steel composite material.

[0110] In some optional instances, the heating temperature of the nickel plating solution is 50-60°C, for example, it can be 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C or 60°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0111] In some optional instances, the stirring speed of the nickel plating solution is 10 to 15 r / min, for example, it can be 10 r / min, 10.5 r / min, 11 r / min, 11.5 r / min, 12 r / min, 12.5 r / min, 13 r / min, 13.5 r / min, 14 r / min, 14.5 r / min or 15 r / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0112] In some optional examples, the waveform of the pulse current output by the dual-pulse power supply is square.

[0113] In some optional instances, the width of the positive pulse output by the dual pulse power supply is 50 to 60 ms, for example, it can be 50ms, 51ms, 52ms, 53ms, 54ms, 55ms, 56ms, 57ms, 58ms, 59ms or 60ms, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0114] In some optional instances, the duty cycle of the positive pulse output by the dual-pulse power supply is 50-60%, for example, it can be 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59% or 60%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0115] As the duty cycle increases, the deposition rate of nickel ions shows a trend of increasing first and then decreasing. This is because, as the duty cycle increases, the pulse width increases, the action time of the pulse current is prolonged, and the deposition reaction of nickel ions intensifies, which is manifested as an increase in the deposition rate of nickel ions. However, the introduction of pulse current increases the deposition rate of nickel ions while also speeding up the consumption of nickel plating solution. Therefore, in the pulse-assisted chemical deposition process, the duty cycle is not the higher the better, but there is an optimal range of values. The present invention specifically limits the duty cycle of the positive pulse output by the dual-pulse power supply to 50-60%.

[0116] Since the pulse current will affect the deposition process by hydrogen evolution reaction and tip effect, thereby affecting the surface morphology of the composite nickel-plated layer, when the duty cycle exceeds 60%, due to the excessively large duty cycle and the long working time of the pulse current, the composite nickel-plated layer is significantly affected by the concentration polarization caused by the accelerated chemical reaction rate, which ultimately leads to the intensification of hydrogen evolution reaction and coarsening of the unit cell; at the same time, the tip effect brought by the pulse current is intensified, causing the surface morphology quality of the composite nickel-plated layer to deteriorate; in addition, when the duty cycle exceeds 60%, the chemical reaction is too intense, causing the nickel plating solution to fail too quickly, which reduces the density and uniformity of the surface morphology of the composite nickel-plated layer, thereby affecting the wear resistance of the composite nickel-plated layer.

[0117] In some optional examples, the current density of the positive pulse output by the double pulse power supply is 2.5-3.5A / dm 2 , for example, it can be 2.5A / dm 2 , 2.6A / dm 2 , 2.7A / dm 2 , 2.8A / dm 2 , 2.9A / dm 2 、3.0A / dm 2 、3.1A / dm 2 , 3.2A / dm 2 、3.3A / dm 2 , 3.4A / dm 2 or 3.5A / dm 2 , but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0118] With the increase of pulse current density, the deposition rate of nickel ions increases first and then decreases. This is because when the current density is between 2.5 and 3.5 A / dm 2 When the current density is within the range, the electrochemical reaction rate increases and the deposition rate of nickel ions accelerates as the current density increases. At the same time, the nano-alumina particles attached with nickel ions can move to the surface of the cladding steel more quickly, which makes more nano-alumina particles be coated in the composite nickel-plating layer, thereby improving the wear resistance of the composite nickel-plating layer.

[0119] When the current density exceeds 3.5A / dm 2 On the one hand, it will lead to the intensification of concentration polarization and hydrogen evolution reaction during the deposition process, the hydrogen evolution rate will be accelerated, and the deposition rate of nickel ions will be reduced; at the same time, when the current density is too high, it will cause the unit cell growth rate to be greater than the nucleation rate, making the unit cell coarse; in addition, the nano-alumina particles are prone to agglomeration on the surface of the composite nickel-plated layer, and the coarse unit cells and agglomerated nano-alumina particles increase the surface roughness and friction coefficient of the composite nickel-plated layer, resulting in the overall wear resistance of the corrosion-resistant high-temperature steel composite material to be reduced, and in severe cases, a loose and porous surface morphology will be produced, which is not conducive to the improvement of the corrosion resistance; on the other hand, excessive pulse current will amplify the influence of the tip effect and edge effect, resulting in the reduction of the density and uniformity of the surface morphology of the composite nickel-plated layer; at the same time, excessive pulse current will cause burrs to appear on the surface of the composite nickel-plated layer, and even accompanied by the formation of flocculent deposits, thereby affecting the wear resistance of the composite nickel-plated layer.

[0120] In some optional instances, the width of the negative pulse output by the dual pulse power supply is 10 to 20 ms, for example, it can be 10ms, 11ms, 12ms, 13ms, 14ms, 15ms, 16ms, 17ms, 18ms, 19ms or 20ms, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0121] In some optional instances, the duty cycle of the negative pulse output by the dual-pulse power supply is 10-20%, for example, it can be 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0122] In some optional examples, the current density of the negative pulse output by the double pulse power supply is 1.2-1.5A / dm 2 , for example, it can be 1.2A / dm 2 , 1.22A / dm 2 , 1.24A / dm 2 , 1.26A / dm 2 , 1.28A / dm 2 , 1.3A / dm 2 , 1.32A / dm 2 , 1.34A / dm 2 , 1.36A / dm 2 , 1.38A / dm 2 , 1.4A / dm 2 , 1.42A / dm 2 , 1.44A / dm2 , 1.46A / dm 2 , 1.48A / dm 2 or 1.5A / dm 2 , but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0123] In some optional examples, the electrochemical deposition time is 10 to 30 minutes, for example, it can be 10 minutes, 12 minutes, 14 minutes, 16 minutes, 18 minutes, 20 minutes, 22 minutes, 24 minutes, 26 minutes, 28 minutes or 30 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0124] In some optional examples, the thickness of the composite nickel plating layer is 15 to 20 μm, for example, it can be 15 μm, 15.5 μm, 16 μm, 16.5 μm, 17 μm, 17.5 μm, 18 μm, 18.5 μm, 19 μm, 19.5 μm or 20 μm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0125] In some optional examples, the nitriding temperature is 350-400°C, for example, it can be 350°C, 355°C, 360°C, 365°C, 370°C, 375°C, 380°C, 385°C, 390°C, 395°C or 400°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0126] In some optional examples, the flow rate of ammonia gas is 8 to 10 L / min, for example, 8.0 L / min, 8.2 L / min, 8.4 L / min, 8.6 L / min, 8.8 L / min, 9.0 L / min, 9.2 L / min, 9.4 L / min, 9.6 L / min, 9.8 L / min or 10.0 L / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0127] In some optional examples, the holding time of the nitriding treatment is 8 to 10 hours, for example, it can be 8.0h, 8.2h, 8.4h, 8.6h, 8.8h, 9.0h, 9.2h, 9.4h, 9.6h, 9.8h or 10.0h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0128] As a preferred technical solution of the present invention, the micro-arc oxidation treatment process specifically includes the following steps:

[0129] The composite steel and stainless steel plate obtained by nitriding treatment are immersed in an electrolyte and electrically connected to the positive electrode and the negative electrode of a power supply respectively; the composite steel is used as an anode and the stainless steel plate is used as a cathode; the cladding layer on the surface of the composite steel is subjected to micro-arc oxidation treatment to form a micro-arc oxidation layer with a porous structure on the surface of the cladding layer; a silane coupling agent is added to an ethanol aqueous solution and mixed evenly to obtain a coupling agent solution; glacial acetic acid is added dropwise to the coupling agent solution to adjust the pH value thereof to acidic; the composite steel after micro-arc oxidation treatment is immersed in the coupling agent solution; after immersion, the composite steel is taken out, cleaned and dried to obtain the corrosion-resistant high-temperature steel composite material.

[0130] In some optional examples, the electrolyte consists of sodium silicate, sodium nitrate, sodium fluoride, potassium hydroxide, calcium acetate and deionized water.

[0131] In some optional examples, the electrolyte consists of sodium silicate, sodium nitrate, sodium fluoride, potassium hydroxide, calcium acetate and deionized water.

[0132] In some optional examples, the concentration of sodium silicate in the electrolyte is 20-30 g / L, for example, it can be 20 g / L, 21 g / L, 22 g / L, 23 g / L, 24 g / L, 25 g / L, 26 g / L, 27 g / L, 28 g / L, 29 g / L or 30 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0133] In some optional examples, the concentration of sodium nitrate in the electrolyte is 10-20 g / L, for example, it can be 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L, 15 g / L, 16 g / L, 17 g / L, 18 g / L, 19 g / L or 20 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0134] In some optional examples, the concentration of sodium fluoride in the electrolyte is 1 to 5 g / L, for example, it can be 1.0 g / L, 1.5 g / L, 2.0 g / L, 2.5 g / L, 3.0 g / L, 3.5 g / L, 4.0 g / L, 4.5 g / L or 5.0 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0135] In some optional examples, the concentration of potassium hydroxide in the electrolyte is 3 to 8 g / L, for example, 3.0 g / L, 3.5 g / L, 4.0 g / L, 4.5 g / L, 5.0 g / L, 5.5 g / L, 6.0 g / L, 6.5 g / L, 7.0 g / L, 7.5 g / L or 8.0 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0136] In some optional examples, the concentration of calcium acetate in the electrolyte is 5 to 15 g / L, for example, 5 g / L, 6 g / L, 7 g / L, 8 g / L, 9 g / L, 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L or 15 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0137] In some optional examples, the temperature of the electrolyte is 50-60°C, for example, it can be 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C or 60°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0138] In some optional examples, the current density of the pulse current output by the power supply is 6 to 8 A / dm 2 , for example, it can be 6.0A / dm 2 、6.2A / dm 2 、6.4A / dm 2 、6.6A / dm 2 、6.8A / dm 2 、7.0A / dm 2 , 7.2A / dm 2 , 7.4A / dm 2 , 7.6A / dm 2 , 7.8A / dm 2 or 8.0A / dm 2 , but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0139] In some optional instances, the duty cycle of the pulse current output by the power supply is 20-30%, for example, it can be 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29% or 30%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0140] In some optional examples, the time of the micro-arc oxidation treatment is 5 to 15 minutes, for example, it can be 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes or 15 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0141] In some optional examples, the silane coupling agent is mixed with the ethanol aqueous solution and stirred for 2 to 3 hours, for example, 2.0 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours or 3.0 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0142] In some optional examples, the mass fraction of the silane coupling agent in the coupling agent solution is 1 to 2 wt%, for example, it can be 1.0 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, 1.4 wt%, 1.5 wt%, 1.6 wt%, 1.7 wt%, 1.8 wt%, 1.9 wt% or 2.0 wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0143] In some optional examples, glacial acetic acid is added dropwise to the coupling agent solution to adjust its pH value to 3-4, for example, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9 or 4.0, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0144] In some optional examples, the composite steel is immersed in the coupling agent solution for 1 to 2 hours, for example, 1.0 h, 1.1 h, 1.2 h, 1.3 h, 1.4 h, 1.5 h, 1.6 h, 1.7 h, 1.8 h, 1.9 h or 2.0 h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0145] In a second aspect, the present invention provides a corrosion-resistant high-temperature steel composite material prepared by the preparation method described in the first aspect.

[0146] In a third aspect, the present invention provides an application of the corrosion-resistant high-temperature steel composite material described in the second aspect, wherein the corrosion-resistant high-temperature steel composite material is used for steel for corrosion-resistant and high-temperature parts.

[0147] Compared with the prior art, the present invention has the following beneficial effects:

[0148] The present invention provides a full-process production method of a corrosion-resistant high-temperature steel composite material, which uses pure iron and alloy materials as raw materials for smelting and refining, casting and tempering heat treatment to obtain an alloy steel with relatively excellent mechanical properties; then the alloy steel is surface-modified by combining three processes of laser cladding, nitriding treatment and micro-arc oxidation to further improve the mechanical properties of the alloy steel product and give the alloy steel excellent corrosion resistance and wear resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0149] Figure 1 A flow chart of the preparation process of the corrosion-resistant high-temperature steel composite material provided in Examples 1-5 of the present invention;

[0150] Figure 2 A schematic diagram of the structure of the casting equipment provided in Examples 1-5 of the present invention;

[0151] Among them, 1-tundish; 2-liquid outlet; 3-vacuum chamber; 4-ingot mold; 5-argon gas source;

[0152] Figure 3 This is a cross-sectional scanning electron microscope image of the corrosion-resistant high-temperature steel composite material prepared in Example 1 of the present invention;

[0153] Figure 4 This is a cross-sectional scanning electron microscope image of the corrosion-resistant high-temperature steel composite material prepared in Comparative Example 3 of the present invention;

[0154] Figure 5 This is a cross-sectional scanning electron microscope image of the corrosion-resistant high-temperature steel composite material prepared in Comparative Example 4 of the present invention;

[0155] Figure 6 This is a surface scanning electron microscope image of the nickel-plated steel material prepared in Example 1 of the present invention;

[0156] Figure 7 This is a surface scanning electron microscope image of the micro-arc oxidation layer prepared in Example 1 of the present invention;

[0157] Figure 8 This is a surface scanning electron microscope image of the corrosion-resistant high-temperature steel composite material prepared in Example 1 of the present invention;

[0158] Fig. 9 This is a scanning electron microscope image of the wear scar surface of the corrosion-resistant high-temperature steel composite material prepared in Example 1 of the present invention after the friction test;

[0159] Fig.10 This is a scanning electron microscope image of the wear scar surface of the corrosion-resistant high-temperature steel composite material prepared in Comparative Example 9 of the present invention after the friction test;

[0160] Fig.11This is a scanning electron microscope image of the wear scar surface of the corrosion-resistant high-temperature steel composite material prepared in Comparative Example 10 of the present invention after the friction test. DETAILED DESCRIPTION

[0161] The technical solution of the present invention is described in detail below in conjunction with specific embodiments and their accompanying drawings. The embodiments recorded herein are specific embodiments of the present invention, which are used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary and should not be construed as limitations on the embodiments of the present invention and the scope of protection of the present invention. In addition to the embodiments recorded herein, those skilled in the art can also adopt other obvious technical solutions based on the contents disclosed in the claims of this application and its specification, including technical solutions that adopt any obvious replacements and modifications to the embodiments recorded herein.

[0162] The chemical reagents used in the embodiments and comparative examples provided by the present invention are all commercially available products, and their brands, specifications, manufacturers and other information are as follows:

[0163] Lime: purity ≥99%, purchased from Shenyang Ketuo Chemical Co., Ltd.;

[0164] Fluorite powder: S50691-500g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0165] Aluminum powder: purity ≥99%, purchased from Fuchen (Tianjin) Chemical Reagent Co., Ltd.;

[0166] Bauxite: industrial grade, purchased from Hubei Dechao Chemical Co., Ltd.;

[0167] Ferro-molybdenum alloy: Fe40Mo60, purity ≥99%, purchased from Shanghai Gelin Technology Co., Ltd.; Ferro-chromium alloy: containing 50-70% chromium, purity ≥99%, purchased from Shanghai Gelin Technology Co., Ltd.; Ferro-manganese alloy: containing 70-80% chromium, purity ≥99%, purchased from Shanghai Gelin Technology Co., Ltd.; Ferrosilicon alloy: FeSi75, purity ≥99%, purchased from Shanghai Gelin Technology Co., Ltd.;

[0168] Sulfuric acid: industrial grade, purchased from Fuchen (Tianjin) Chemical Reagent Co., Ltd.;

[0169] Nitric acid: industrial grade, purchased from Fuchen (Tianjin) Chemical Reagent Co., Ltd.;

[0170] Hydrochloric acid: industrial grade, purchased from Fuchen (Tianjin) Chemical Reagent Co., Ltd.;

[0171] White corundum: A00680, purchased from Wuhan Jiyesheng Chemical Co., Ltd.;

[0172] Tungsten carbide powder: KL819965, purchased from Shanghai Kanglang Biotechnology Co., Ltd.;

[0173] Nickel powder: purity ≥99.8%, purchased from Shanghai Gelin Technology Co., Ltd.;

[0174] Cubic boron nitride powder: S40088-100g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.; Titanium dioxide powder: S26013-100g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0175] Cerium dioxide powder: WD8009, purchased from Hubei Wonder Chemical Co., Ltd.;

[0176] Anhydrous ethanol: purity ≥99%, purchased from Jinan Hongteng Weiye New Materials Co., Ltd.;

[0177] Polyvinyl alcohol: S30196-500g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0178] Nickel sulfate: purity ≥ 98.5%, purchased from Fuchen (Tianjin) Chemical Reagent Co., Ltd.;

[0179] Sodium citrate: S67462-100g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0180] Sodium acetate: purity ≥99%, purchased from Langfang Naco New Materials Technology Co., Ltd.;

[0181] Thiourea: purity ≥99%, purchased from Nanjing Chemical Reagent Co., Ltd.;

[0182] Potassium iodide: S30393-25g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0183] Succinic acid: S30140-100 g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0184] Sodium dodecyl sulfate: S15012-100g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0185] Sodium hypophosphite: purity ≥99%, purchased from Fuchen (Tianjin) Chemical Reagent Co., Ltd.

[0186] Alumina sol: purity ≥99%, purchased from Hubei Chengfeng Chemical Co., Ltd.

[0187] Sodium silicate: purity ≥99%, purchased from Hubei Xinrunde Chemical Co., Ltd.

[0188] Sodium nitrate: purity ≥99%, purchased from Fuchen (Tianjin) Chemical Reagent Co., Ltd.;

[0189] Sodium fluoride: purity ≥99%, purchased from Nanjing Chemical Reagent Co., Ltd.

[0190] Potassium hydroxide: purity ≥99%, purchased from Langfang Qianyao Technology Co., Ltd.

[0191] Calcium acetate: S67046-25g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0192] Silane coupling agent KH550: S15028-500ml, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0193] Silane coupling agent KH560: S15029-500ml, purchased from Shanghai Yuanye Biotechnology Co., Ltd.;

[0194] Silane coupling agent KH570: S15030-500ml, purchased from Shanghai Yuanye Biotechnology Co., Ltd.

[0195] Example 1

[0196] This embodiment provides a method for preparing a corrosion-resistant high-temperature steel composite material. Figure 1 As shown, the preparation method specifically comprises the following steps:

[0197] S1. Smelting and refining: pure iron is put into a smelting furnace for heating and smelting to form molten iron, the heating and smelting temperature is 1580°C, and the holding time is 5 hours; then, the molten iron is transferred to an LF refining furnace and the temperature of the molten iron is adjusted to 1650°C, molybdenum-iron alloy, chromium-iron alloy, manganese-iron alloy and silicon-iron alloy are added to the molten iron in sequence, and argon gas is blown into the bottom of the molten iron at a flow rate of 300L / min for stirring, and the argon is blown and stirred for 40 minutes and then kept warm for 10 minutes to obtain alloy steel liquid;

[0198] Add desulfurizer and dephosphorizer to the alloy steel liquid and blow argon gas at a flow rate of 500L / min from the bottom of the alloy steel liquid to stir it. The desulfurizer is composed of lime, fluorite powder and aluminum powder. 8kg lime, 2kg fluorite powder and 0.5kg aluminum powder are added to each ton of alloy steel liquid. The dephosphorizer is composed of lime and bauxite. 7kg lime and 2.5kg bauxite are added to each ton of alloy steel liquid. After blowing argon and stirring for 3 minutes, keep warm for 10 minutes. After the insulation is completed, the alloy steel is The molten steel was transferred to a VD vacuum furnace and evacuated to 50 Pa and maintained at a pressure of 30 min, and then argon was blown into the molten steel from the bottom at a flow rate of 3 L / min and continued to blow argon for 20 min to obtain a refined molten steel. The mass fraction of each element in the refined molten steel was controlled within the following ranges: carbon 0.01wt%, molybdenum 2.0wt%, chromium 17wt%, manganese 1.2wt%, silicon 0.6wt%, sulfur 0.001wt% and phosphorus 0.01wt%, and the balance was iron;

[0199] S2, casting: the refined molten steel obtained in step S1 is injected into a casting device for vacuum casting, such as Figure 2As shown, the casting equipment includes a vacuum chamber 3, a steel ingot mold 4 and a tundish 1. The steel ingot mold 4 is located inside the vacuum chamber 3, the tundish 1 is located on the top of the vacuum chamber 3, and a liquid outlet 2 is provided at the bottom of the tundish 1. The tundish 1 is connected to the steel ingot mold 4 through the liquid outlet 2, and the liquid outlet 2 is externally connected to an argon gas source 5;

[0200] The vacuum casting process includes: preheating the steel ingot mold 4 to 200°C, adjusting the temperature of the refined steel liquid obtained in step S1 to 1520°C, and then injecting it into the tundish 1 at a speed of 3t / min, and the argon gas source 5 introduces argon gas to the liquid outlet 2 at a flow rate of 5L / min, and the refined steel liquid is mixed with the argon gas when flowing through the liquid outlet 2 and then flows into the preheated steel ingot mold 4. After the refined steel liquid is completely injected into the steel ingot mold 4, it is naturally cooled to room temperature, and the alloy steel casting is obtained after demolding;

[0201] S3, quenching and tempering heat treatment: the alloy steel casting obtained in step S2 is heated to 900°C at a heating rate of 80°C / h, and kept at this temperature for 3h. After the insulation, the primary annealing treatment is completed; then, the alloy steel casting after the primary annealing treatment is cooled to 680°C with the furnace, and kept at this temperature for 5h. After the insulation, the alloy steel casting is taken out of the furnace and air-cooled to room temperature to complete the secondary annealing treatment;

[0202] The alloy steel casting after the secondary annealing treatment is heated to 850°C at a heating rate of 60°C / h, and kept at this temperature for 60 minutes. After the insulation, the alloy steel casting is taken out of the furnace and immediately immersed in cooling water at 10°C for 90 minutes to achieve rapid cooling of the alloy steel casting. The cooling rate of the alloy steel casting in the cooling water is 160°C / h, and the quenching treatment is completed. After the quenching treatment, the alloy steel material is obtained;

[0203] S4, sandblasting roughening: use 400 mesh fine sandpaper to grind the surface of the alloy steel obtained in step S3 to remove the oxide scale on the surface of the alloy steel; use clean water to rinse and dry the polished surface of the alloy steel, soak the dried alloy steel in a 40wt% sulfuric acid solution, the temperature of the sulfuric acid solution is 50°C, soak for 40 minutes, take out the alloy steel and soak it in an ultrasonic device filled with clean water, ultrasonically clean and dry the alloy steel, the ultrasonic power is 800W, and the ultrasonic cleaning time is 30 minutes;

[0204] The alloy steel after ultrasonic cleaning was preheated to 50°C, and the surface of the dried alloy steel was sandblasted with white corundum with a particle size of 1 mm. The sandblasting pressure was 0.6 MPa, the sandblasting distance was 100 mm, the angle between the nozzle axis and the surface of the alloy steel was 60°, and the sandblasting time was 3 min. After the sandblasting, the alloy steel was cleaned and dried;

[0205] The sandblasted alloy steel is immersed in a passivation solution at 60° C. for surface passivation treatment, wherein the mass fraction of citric acid in the passivation solution is 15wt%, and the mass fraction of ethylenediaminetetraacetic acid is 0.5wt%; after immersion for 30 minutes, the alloy steel is cleaned and dried to obtain a sandblasted steel;

[0206] S5, laser cladding: 50 parts of aluminum powder, 30 parts of tungsten carbide powder, 8.5 parts of nickel powder, 8 parts of cubic boron nitride powder, 3 parts of titanium dioxide powder and 0.5 parts of cerium dioxide powder are mixed and ball-milled to obtain a cladding material; the cladding material is mixed with a binder solution at a ratio of 1 g:0.2 mL to obtain a paste-like cladding slurry; wherein the binder solution is composed of anhydrous ethanol and polyvinyl alcohol in a mass ratio of 10:1;

[0207] The cladding slurry is uniformly coated on the surface of the sandblasted steel obtained in step S4, the coating thickness of the cladding slurry is 1 mm, and a cladding slurry layer is formed after drying; the sandblasted steel with the cladding slurry layer is placed in a cladding device, argon gas is introduced into the cavity of the cladding device, and the argon gas introduction flow rate is 8 L / min. In the argon atmosphere, a laser is used to perform laser cladding on the cladding slurry layer, the laser power is set to 3 kW, the spot diameter is set to 3 mm, and the scanning speed is set to 200 mm / min. After cooling, a cladding layer is formed on the surface of the sandblasted steel, and a cladding steel consisting of a cladding layer and a sandblasted steel is obtained;

[0208] S6, nitriding treatment: nickel sulfate, sodium citrate, sodium acetate, thiourea, potassium iodide, succinic acid, sodium dodecyl sulfate, sodium hypophosphite, alumina sol and deionized water are mixed to obtain a nickel plating solution, wherein the concentration of nickel sulfate in the nickel plating solution is 25 g / L, the concentration of sodium citrate is 25 g / L, the concentration of sodium acetate is 15 g / L, the concentration of thiourea is 0.1 mg / L, the concentration of potassium iodide is 1 mg / L, the concentration of succinic acid is 15 g / L, the concentration of sodium dodecyl sulfate is 0.2 g / L, the concentration of sodium hypophosphite is 30 g / L, and the concentration of alumina sol is 15 mL / L;

[0209] The prepared nickel plating solution is poured into a constant temperature water bath, and the nickel plating solution is heated and stirred. The heating temperature of the nickel plating solution is 50°C and the stirring speed is 10r / min. The clad steel and nickel plate obtained in step S5 are immersed in the prepared nickel plating solution and are electrically connected to the negative electrode and the positive electrode of the dual pulse power supply respectively. The waveform of the pulse current output by the dual pulse power supply is square, the width of the positive pulse is 50ms, the duty cycle is 50%, and the current density is 2.5A / dm 2 ; The width of the negative pulse is 10ms, the duty cycle is 10%, and the current density is 1.2A / dm 2; Electrochemically depositing the cladding steel for 30 minutes to form a composite nickel coating with a thickness of 20 μm on the surface of the cladding steel to obtain a nickel-plated steel;

[0210] The nickel-plated steel is placed in a heat treatment device, ammonia gas is introduced into the cavity of the heat treatment device, and the flow rate of ammonia gas is 8 L / min. The nickel-plated steel is heated to 350° C. and kept warm for 10 hours to perform nitriding treatment to obtain a composite steel;

[0211] S7, micro-arc oxidation: immerse the composite steel and stainless steel plate obtained in step S6 in an electrolyte at 50°C and electrically connect them to the positive and negative electrodes of a power source, respectively. The concentration of sodium silicate in the electrolyte is 20 g / L, the concentration of sodium nitrate is 20 g / L, the concentration of sodium fluoride is 1 g / L, the concentration of potassium hydroxide is 8 g / L, and the concentration of calcium acetate is 15 g / L; the current density of the pulse current output by the power source is 6 A / dm 2 , the duty cycle is 20%; using the composite steel as the anode and the stainless steel plate as the cathode, the cladding layer on the surface of the composite steel is subjected to micro-arc oxidation treatment for 15 minutes to form a micro-arc oxidation layer with a porous structure on the surface of the cladding layer;

[0212] The silane coupling agent KH550 is added to an ethanol aqueous solution (the volume ratio of ethanol to deionized water is 7:3), and the mixture is stirred for 2 hours to obtain a 1wt% coupling agent solution. Glacial acetic acid is added dropwise to the coupling agent solution to adjust its pH value to 3. The composite steel obtained after micro-arc oxidation treatment is immersed in the prepared coupling agent solution, and after soaking in the coupling agent solution for 2 hours, the composite steel is taken out, cleaned and dried to obtain the corrosion-resistant high-temperature steel composite material.

[0213] The surface morphology of the nickel-plated steel prepared in this example was observed using a scanning electron microscope, and the following results were obtained: Figure 6 The surface scanning electron microscope image shown is Figure 6 It can be seen that due to the incorporation of alumina sol, the surface of the nickel-plated steel formed after electrochemical deposition is uniformly loaded with nano-alumina particles.

[0214] The microscopic morphology of the micro-arc oxidation layer on the surface of the corrosion-resistant high-temperature steel composite material prepared in this embodiment was observed using a scanning electron microscope, and the following results were obtained: Figure 7 The surface scanning electron microscope image shown is Figure 7 It can be seen that the micro-arc oxidation layer has a three-dimensional porous structure.

[0215] The surface microstructure of the corrosion-resistant high-temperature steel composite material prepared in this embodiment was observed using a scanning electron microscope, and the following results were obtained: Figure 8 The surface scanning electron microscope image shown is Figure 8It can be seen that after immersion in the silane coupling agent solution, the pore structure of the micro-arc oxidation layer on the surface of the corrosion-resistant high-temperature steel composite material is blocked by the silane coupling agent.

[0216] Example 2

[0217] This embodiment provides a method for preparing a corrosion-resistant high-temperature steel composite material. Figure 1 As shown, the preparation method specifically comprises the following steps:

[0218] S1. Smelting and refining: pure iron is put into a smelting furnace for heating and smelting to form molten iron, the heating and smelting temperature is 1600° C., and the holding time is 4.8 hours; then, the molten iron is transferred to an LF refining furnace and the temperature of the molten iron is adjusted to 1680° C., molybdenum-iron alloy, chromium-iron alloy, manganese-iron alloy and silicon-iron alloy are added to the molten iron in sequence, and argon gas is blown into the bottom of the molten iron at a flow rate of 320 L / min for stirring, and the argon is blown and stirred for 38 minutes and then kept warm for 12 minutes to obtain alloy steel liquid;

[0219] Desulfurizer and dephosphorizer were added to the alloy steel liquid, and argon was blown in from the bottom of the alloy steel liquid at a flow rate of 520 L / min for stirring. The desulfurizer consisted of lime, fluorite powder and aluminum powder, and 8.5 kg of lime, 1.8 kg of fluorite powder and 0.6 kg of aluminum powder were added to each ton of alloy steel liquid. The dephosphorizer consisted of lime and bauxite, and 7.5 kg of lime and 2.2 kg of bauxite were added to each ton of alloy steel liquid. After argon blowing and stirring for 3.5 minutes, the mixture was kept warm for 12 minutes. After the heat preservation was completed, the alloy was The molten steel was transferred to a VD vacuum furnace and evacuated to 52 Pa and maintained at this pressure for 28 minutes, and then argon was blown into the alloy steel liquid from the bottom at a flow rate of 3.5 L / min and the argon blowing was continued for 18 minutes to obtain a refined molten steel, wherein the mass fraction of each element in the refined molten steel was controlled within the following ranges: carbon 0.012 wt%, molybdenum 2.2 wt%, chromium 16.8 wt%, manganese 1.3 wt%, silicon 0.58 wt%, sulfur 0.0015 wt% and phosphorus 0.02 wt%, and the remainder was iron;

[0220] S2, casting: the refined molten steel obtained in step S1 is injected into a casting device for vacuum casting, such as Figure 2 As shown, the casting equipment includes a vacuum chamber 3, a steel ingot mold 4 and a tundish 1. The steel ingot mold 4 is located inside the vacuum chamber 3, the tundish 1 is located on the top of the vacuum chamber 3, and a liquid outlet 2 is provided at the bottom of the tundish 1. The tundish 1 is connected to the steel ingot mold 4 through the liquid outlet 2, and the liquid outlet 2 is externally connected to an argon gas source 5;

[0221] The vacuum casting process includes: preheating the steel ingot mold 4 to 210°C, adjusting the temperature of the refined steel liquid obtained in step S1 to 1522°C, and then injecting it into the tundish 1 at a speed of 4t / min, and the argon gas source 5 introduces argon gas to the liquid outlet 2 at a flow rate of 6L / min, and the refined steel liquid is mixed with the argon gas when flowing through the liquid outlet 2 and then flows into the preheated steel ingot mold 4, and after the refined steel liquid is completely injected into the steel ingot mold 4, it is naturally cooled to room temperature, and the alloy steel casting is obtained after demolding;

[0222] S3, quenching and tempering heat treatment: the alloy steel casting obtained in step S2 is heated to 910°C at a heating rate of 85°C / h, and kept at this temperature for 2.8h. After the insulation, the primary annealing treatment is completed; then, the alloy steel casting after the primary annealing treatment is cooled to 682°C with the furnace, and kept at this temperature for 4.8h. After the insulation, the alloy steel casting is taken out of the furnace and air-cooled to room temperature to complete the secondary annealing treatment;

[0223] The alloy steel casting after the secondary annealing treatment is heated to 860°C at a heating rate of 62°C / h, and kept at this temperature for 58 minutes. After the insulation is completed, the alloy steel casting is taken out of the furnace and immediately immersed in cooling water at 15°C for 80 minutes to achieve rapid cooling of the alloy steel casting. The cooling rate of the alloy steel casting in the cooling water is 158°C / h, and the quenching treatment is completed. After the quenching treatment is completed, the alloy steel material is obtained;

[0224] S4, sandblasting roughening: use 400 mesh fine sandpaper to grind the surface of the alloy steel obtained in step S3 to remove the oxide scale on the surface of the alloy steel; use clean water to rinse and dry the polished surface of the alloy steel, soak the dried alloy steel in a 42wt% sulfuric acid solution at a temperature of 48°C, soak for 38 minutes, take out the alloy steel and soak it in an ultrasonic device filled with clean water, ultrasonically clean and dry the alloy steel, the ultrasonic power is 850W, and the ultrasonic cleaning time is 28 minutes;

[0225] The alloy steel after ultrasonic cleaning was preheated to 52°C, and the surface of the dried alloy steel was sandblasted with white corundum with a particle size of 1.5 mm. The sandblasting pressure was 0.58 MPa, the sandblasting distance was 110 mm, the angle between the nozzle axis and the surface of the alloy steel was 62°, and the sandblasting time was 4 min. After the sandblasting, the alloy steel was cleaned and dried;

[0226] The sandblasted alloy steel is immersed in a passivation solution at 62° C. for surface passivation treatment, wherein the mass fraction of citric acid in the passivation solution is 18wt%, and the mass fraction of ethylenediaminetetraacetic acid is 0.8wt%; after immersion for 28 minutes, the alloy steel is cleaned and dried to obtain a sandblasted steel;

[0227] S5, laser cladding: 52 parts of aluminum powder, 23 parts of tungsten carbide powder, 10 parts of nickel powder, 10 parts of cubic boron nitride powder, 3.8 parts of titanium dioxide powder and 1.2 parts of cerium dioxide powder are mixed and ball-milled to obtain a cladding material; the cladding material is mixed with a binder solution at a ratio of 1 g:0.22 mL to obtain a paste-like cladding slurry; wherein the binder solution is composed of anhydrous ethanol and polyvinyl alcohol in a mass ratio of 12:1;

[0228] The cladding slurry is uniformly coated on the surface of the sandblasted steel obtained in step S4, the coating thickness of the cladding slurry is 1.2 mm, and a cladding slurry layer is formed after drying; the sandblasted steel with the cladding slurry layer is placed in a cladding device, argon gas is introduced into the cavity of the cladding device, and the argon gas flow rate is 10 L / min. In the argon atmosphere, a laser is used to perform laser cladding on the cladding slurry layer, the laser power is set to 3.2 kW, the spot diameter is set to 3.5 mm, and the scanning speed is set to 180 mm / min. After cooling, a cladding layer is formed on the surface of the sandblasted steel, and a cladding steel consisting of a cladding layer and a sandblasted steel is obtained;

[0229] S6, nitriding treatment: nickel sulfate, sodium citrate, sodium acetate, thiourea, potassium iodide, succinic acid, sodium dodecyl sulfate, sodium hypophosphite, alumina sol and deionized water are mixed to obtain a nickel plating solution, wherein the concentration of nickel sulfate in the nickel plating solution is 28 g / L, the concentration of sodium citrate is 22 g / L, the concentration of sodium acetate is 18 g / L, the concentration of thiourea is 0.2 mg / L, the concentration of potassium iodide is 2 mg / L, the concentration of succinic acid is 18 g / L, the concentration of sodium dodecyl sulfate is 0.3 g / L, the concentration of sodium hypophosphite is 28 g / L, and the concentration of alumina sol is 18 mL / L;

[0230] The prepared nickel plating solution is poured into a constant temperature water bath, and the nickel plating solution is heated and stirred. The heating temperature of the nickel plating solution is 52°C and the stirring speed is 11r / min. The cladding steel and nickel plate obtained in step S5 are immersed in the prepared nickel plating solution and are electrically connected to the negative electrode and the positive electrode of the dual pulse power supply respectively. The waveform of the pulse current output by the dual pulse power supply is square, the width of the positive pulse is 52ms, the duty cycle is 52%, and the current density is 2.8A / dm 2 ; The width of the negative pulse is 12ms, the duty cycle is 12%, and the current density is 1.3A / dm 2 ; Electrochemically depositing the cladding steel for 25 minutes to form a composite nickel coating with a thickness of 18 μm on the surface of the cladding steel to obtain a nickel-plated steel;

[0231] The nickel-plated steel is placed in a heat treatment device, ammonia gas is introduced into the cavity of the heat treatment device, and the flow rate of ammonia gas is 8.5 L / min. The nickel-plated steel is heated to 360° C. and kept warm for 9.5 hours to perform nitriding treatment to obtain a composite steel;

[0232] S7, micro-arc oxidation: immerse the composite steel and stainless steel plate obtained in step S6 in an electrolyte at 52°C and electrically connect them to the positive and negative electrodes of a power source, respectively. The concentration of sodium silicate in the electrolyte is 22 g / L, the concentration of sodium nitrate is 18 g / L, the concentration of sodium fluoride is 2 g / L, the concentration of potassium hydroxide is 7 g / L, and the concentration of calcium acetate is 12 g / L; the current density of the pulse current output by the power source is 6.5 A / dm 2 , the duty cycle is 22%; using the composite steel as the anode and the stainless steel plate as the cathode, the cladding layer on the surface of the composite steel is subjected to micro-arc oxidation treatment for 12 minutes to form a micro-arc oxidation layer with a porous structure on the surface of the cladding layer;

[0233] The silane coupling agent KH550 is added to an ethanol aqueous solution (the volume ratio of ethanol to deionized water is 7:3), and the mixture is mixed and stirred for 2.2 hours to obtain a 1.2wt% coupling agent solution. Glacial acetic acid is added dropwise to the coupling agent solution to adjust its pH value to 3.2. The composite steel obtained after micro-arc oxidation treatment is immersed in the prepared coupling agent solution, and after soaking in the coupling agent solution for 1.8 hours, the composite steel is taken out, cleaned and dried to obtain the corrosion-resistant high-temperature steel composite material.

[0234] Example 3

[0235] This embodiment provides a method for preparing a corrosion-resistant high-temperature steel composite material. Figure 1 As shown, the preparation method specifically comprises the following steps:

[0236] S1. Smelting and refining: pure iron is put into a smelting furnace for heating and smelting to form molten iron, the heating and smelting temperature is 1620° C., and the holding time is 4.5 h; then, the molten iron is transferred to an LF refining furnace and the temperature of the molten iron is adjusted to 1700° C., molybdenum-iron alloy, chromium-iron alloy, manganese-iron alloy and silicon-iron alloy are added to the molten iron in sequence, and argon gas is blown into the bottom of the molten iron at a flow rate of 350 L / min for stirring, and the argon is blown and stirred for 35 min and then kept warm for 15 min to obtain alloy steel liquid;

[0237] Add desulfurizer and dephosphorizer to the alloy steel liquid and blow argon gas at a flow rate of 550L / min from the bottom of the alloy steel liquid to stir it. The desulfurizer is composed of lime, fluorite powder and aluminum powder. 9kg lime, 1.5kg fluorite powder and 0.8kg aluminum powder are added to each ton of alloy steel liquid. The dephosphorizer is composed of lime and bauxite. 8kg lime and 2kg bauxite are added to each ton of alloy steel liquid. After argon blowing and stirring for 4 minutes, keep warm for 15 minutes. After the insulation is completed, turn the alloy steel liquid into Move to a VD vacuum furnace, evacuate to 55 Pa and maintain the pressure for 25 minutes, then blow argon gas into the alloy steel liquid from the bottom at a flow rate of 4L / min and continue blowing argon for 15 minutes to obtain refined steel liquid, and the mass fraction of each element in the refined steel liquid is controlled within the following range: carbon 0.015wt%, molybdenum 2.3wt%, chromium 16.5wt%, manganese 1.4wt%, silicon 0.55wt%, sulfur 0.002wt% and phosphorus 0.03wt%, and the balance is iron;

[0238] S2, casting: the refined molten steel obtained in step S1 is injected into a casting device for vacuum casting, such as Figure 2 As shown, the casting equipment includes a vacuum chamber 3, a steel ingot mold 4 and a tundish 1. The steel ingot mold 4 is located inside the vacuum chamber 3, the tundish 1 is located on the top of the vacuum chamber 3, and a liquid outlet 2 is provided at the bottom of the tundish 1. The tundish 1 is connected to the steel ingot mold 4 through the liquid outlet 2, and the liquid outlet 2 is externally connected to an argon gas source 5;

[0239] The vacuum casting process includes: preheating the steel ingot mold 4 to 220°C, adjusting the temperature of the refined steel liquid obtained in step S1 to 1525°C, and then injecting it into the tundish 1 at a speed of 5t / min, and the argon gas source 5 introduces argon gas to the liquid outlet 2 at a flow rate of 7L / min, and the refined steel liquid is mixed with the argon gas when flowing through the liquid outlet 2 and then flows into the preheated steel ingot mold 4. After the refined steel liquid is completely injected into the steel ingot mold 4, it is naturally cooled to room temperature, and the alloy steel casting is obtained after demolding;

[0240] S3, quenching and tempering heat treatment: the alloy steel casting obtained in step S2 is heated to 920°C at a heating rate of 90°C / h, and kept at this temperature for 2.5 hours. After the insulation, the primary annealing treatment is completed; then, the alloy steel casting after the primary annealing treatment is cooled to 685°C with the furnace, and kept at this temperature for 4.5 hours. After the insulation, the alloy steel casting is taken out of the furnace and air-cooled to room temperature to complete the secondary annealing treatment;

[0241] The alloy steel casting after the secondary annealing treatment is heated to 870°C at a heating rate of 65°C / h, and kept at this temperature for 55 minutes. After the insulation is completed, the alloy steel casting is taken out of the furnace and immediately immersed in cooling water at 20°C for 70 minutes to achieve rapid cooling of the alloy steel casting. The cooling rate of the alloy steel casting in the cooling water is 155°C / h, and the quenching treatment is completed. After the quenching treatment is completed, the alloy steel material is obtained;

[0242] S4, sandblasting roughening: use 400 mesh fine sandpaper to grind the surface of the alloy steel obtained in step S3 to remove the oxide scale on the surface of the alloy steel; use clean water to rinse and dry the polished surface of the alloy steel, soak the dried alloy steel in a 45wt% nitric acid solution, the temperature of the nitric acid solution is 45°C, soak for 35 minutes, take out the alloy steel and soak it in an ultrasonic device filled with clean water, ultrasonically clean and dry the alloy steel, the ultrasonic power is 900W, and the ultrasonic cleaning time is 25 minutes;

[0243] The alloy steel after ultrasonic cleaning was preheated to 55°C, and the surface of the dried alloy steel was sandblasted with white corundum with a particle size of 2 mm. The sandblasting pressure was 0.55 MPa, the sandblasting distance was 120 mm, the angle between the nozzle axis and the surface of the alloy steel was 65°, and the sandblasting time was 5 min. After the sandblasting, the alloy steel was cleaned and dried.

[0244] The alloy steel after sandblasting is immersed in a passivation solution at 65° C. for surface passivation treatment, wherein the mass fraction of citric acid in the passivation solution is 20wt%, and the mass fraction of ethylenediaminetetraacetic acid is 1wt%; after immersion for 25 minutes, the alloy steel is cleaned and dried to obtain a sandblasted steel;

[0245] S5, laser cladding: 55 parts of aluminum powder, 24.5 parts of tungsten carbide powder, 8 parts of nickel powder, 8 parts of cubic boron nitride powder, 3.5 parts of titanium dioxide powder and 1 part of cerium dioxide powder are mixed and ball-milled to obtain a cladding material; the cladding material is mixed with a binder solution at a ratio of 1 g:0.25 mL to obtain a paste-like cladding slurry; wherein the binder solution is composed of anhydrous ethanol and polyvinyl alcohol in a mass ratio of 15:1;

[0246] The cladding slurry is uniformly coated on the surface of the sandblasted steel obtained in step S4, the coating thickness of the cladding slurry is 1.5 mm, and a cladding slurry layer is formed after drying; the sandblasted steel with the cladding slurry layer is placed in a cladding device, argon gas is introduced into the cavity of the cladding device, and the argon gas flow rate is 12 L / min. In the argon atmosphere, a laser is used to perform laser cladding on the cladding slurry layer, the laser power is set to 3.5 kW, the spot diameter is set to 4 mm, and the scanning speed is set to 170 mm / min. After cooling, a cladding layer is formed on the surface of the sandblasted steel, and a cladding steel consisting of a cladding layer and a sandblasted steel is obtained;

[0247] S6, nitriding treatment: nickel sulfate, sodium citrate, sodium acetate, thiourea, potassium iodide, succinic acid, sodium dodecyl sulfate, sodium hypophosphite, alumina sol and deionized water are mixed to obtain a nickel plating solution, wherein the concentration of nickel sulfate in the nickel plating solution is 30 g / L, the concentration of sodium citrate is 20 g / L, the concentration of sodium acetate is 20 g / L, the concentration of thiourea is 0.3 mg / L, the concentration of potassium iodide is 3 mg / L, the concentration of succinic acid is 20 g / L, the concentration of sodium dodecyl sulfate is 0.4 g / L, the concentration of sodium hypophosphite is 25 g / L, and the concentration of alumina sol is 20 mL / L;

[0248] The prepared nickel plating solution is poured into a constant temperature water bath, and the nickel plating solution is heated and stirred. The heating temperature of the nickel plating solution is 55°C and the stirring speed is 12r / min. The clad steel and nickel plate obtained in step S5 are immersed in the prepared nickel plating solution and are electrically connected to the negative electrode and the positive electrode of the dual pulse power supply respectively. The waveform of the pulse current output by the dual pulse power supply is square, the width of the positive pulse is 55ms, the duty cycle is 55%, and the current density is 3A / dm 2 ; The width of the negative pulse is 15ms, the duty cycle is 15%, and the current density is 1.3A / dm 2 ; Electrochemically depositing the cladding steel for 20 minutes to form a composite nickel coating with a thickness of 17 μm on the surface of the cladding steel to obtain a nickel-plated steel;

[0249] The nickel-plated steel is placed in a heat treatment device, ammonia gas is introduced into the cavity of the heat treatment device, and the flow rate of ammonia gas is 9 L / min. The nickel-plated steel is heated to 370° C. and kept warm for 9 hours to perform nitriding treatment to obtain a composite steel;

[0250] S7, micro-arc oxidation: immerse the composite steel and stainless steel plate obtained in step S6 in an electrolyte at 55°C and electrically connect them to the positive and negative electrodes of a power source, respectively. The concentration of sodium silicate in the electrolyte is 25 g / L, the concentration of sodium nitrate is 15 g / L, the concentration of sodium fluoride is 3 g / L, the concentration of potassium hydroxide is 6 g / L, and the concentration of calcium acetate is 10 g / L; the current density of the pulse current output by the power source is 7 A / dm 2, the duty cycle is 25%; using the composite steel as the anode and the stainless steel plate as the cathode, the cladding layer on the surface of the composite steel is subjected to micro-arc oxidation treatment for 10 minutes to form a micro-arc oxidation layer with a porous structure on the surface of the cladding layer;

[0251] The silane coupling agent KH560 is added to an ethanol aqueous solution (the volume ratio of ethanol to deionized water is 7:3), and the mixture is stirred for 2.5 hours to obtain a 1.5wt% coupling agent solution. Glacial acetic acid is added dropwise to the coupling agent solution to adjust its pH value to 3.5. The composite steel obtained after micro-arc oxidation treatment is immersed in the prepared coupling agent solution, and after soaking in the coupling agent solution for 1.5 hours, the composite steel is taken out, cleaned and dried to obtain the corrosion-resistant high-temperature steel composite material.

[0252] Example 4

[0253] This embodiment provides a method for preparing a corrosion-resistant high-temperature steel composite material. Figure 1 As shown, the preparation method specifically comprises the following steps:

[0254] S1. Smelting and refining: pure iron is put into a smelting furnace for heating and smelting to form molten iron, the heating and smelting temperature is 1630° C., and the holding time is 4.2 h; then, the molten iron is transferred to an LF refining furnace and the temperature of the molten iron is adjusted to 1720° C., molybdenum-iron alloy, chromium-iron alloy, manganese-iron alloy and silicon-iron alloy are added to the molten iron in sequence, and argon gas is blown into the bottom of the molten iron at a flow rate of 380 L / min for stirring, and the argon is blown and stirred for 32 min and then kept warm for 18 min to obtain alloy steel liquid;

[0255] Desulfurizer and dephosphorizer were added to the alloy steel liquid, and argon was blown in from the bottom of the alloy steel liquid at a flow rate of 580 L / min for stirring. The desulfurizer consisted of lime, fluorite powder and aluminum powder, and 9.5 kg of lime, 1.2 kg of fluorite powder and 0.9 kg of aluminum powder were added to each ton of alloy steel liquid. The dephosphorizer consisted of lime and bauxite, and 8.5 kg of lime and 1.8 kg of bauxite were added to each ton of alloy steel liquid. After argon blowing and stirring for 4.5 minutes, the mixture was kept warm for 18 minutes. After the heat preservation was completed, the alloy was The molten steel was transferred to a VD vacuum furnace and evacuated to 58 Pa and maintained at this pressure for 22 minutes, and then argon was blown into the alloy steel from the bottom at a flow rate of 4.5 L / min and continued to blow argon for 12 minutes to obtain a refined molten steel. The mass fraction of each element in the refined molten steel was controlled within the following ranges: carbon 0.018 wt%, molybdenum 2.4 wt%, chromium 16.2 wt%, manganese 1.4 wt%, silicon 0.52 wt%, sulfur 0.0025 wt% and phosphorus 0.04 wt%, and the remainder was iron;

[0256] S2, casting: the refined molten steel obtained in step S1 is injected into a casting device for vacuum casting, such as Figure 2 As shown, the casting equipment includes a vacuum chamber 3, a steel ingot mold 4 and a tundish 1. The steel ingot mold 4 is located inside the vacuum chamber 3, the tundish 1 is located on the top of the vacuum chamber 3, and a liquid outlet 2 is provided at the bottom of the tundish 1. The tundish 1 is connected to the steel ingot mold 4 through the liquid outlet 2, and the liquid outlet 2 is externally connected to an argon gas source 5;

[0257] The vacuum casting process includes: preheating the steel ingot mold 4 to 230°C, adjusting the temperature of the refined steel liquid obtained in step S1 to 1528°C, and then injecting it into the tundish 1 at a speed of 7t / min, and the argon gas source 5 introduces argon gas to the liquid outlet 2 at a flow rate of 7L / min, and the refined steel liquid is mixed with the argon gas when flowing through the liquid outlet 2 and then flows into the preheated steel ingot mold 4. After the refined steel liquid is completely injected into the steel ingot mold 4, it is naturally cooled to room temperature, and the alloy steel casting is obtained after demolding;

[0258] S3, quenching and tempering heat treatment: the alloy steel casting obtained in step S2 is heated to 940°C at a heating rate of 95°C / h, and kept at this temperature for 2.2h. After the insulation, the primary annealing treatment is completed; then, the alloy steel casting after the primary annealing treatment is cooled to 688°C with the furnace, and kept at this temperature for 4.2h. After the insulation, the alloy steel casting is taken out of the furnace and air-cooled to room temperature to complete the secondary annealing treatment;

[0259] The alloy steel casting after the secondary annealing treatment is heated to 880°C at a heating rate of 68°C / h, and kept at this temperature for 52 minutes. After the insulation is completed, the alloy steel casting is taken out of the furnace and immediately immersed in cooling water at 25°C for 70 minutes to achieve rapid cooling of the alloy steel casting. The cooling rate of the alloy steel casting in the cooling water is 152°C / h, and the quenching treatment is completed. After the quenching treatment is completed, the alloy steel material is obtained;

[0260] S4, sandblasting roughening: use 500 mesh fine sandpaper to grind the surface of the alloy steel obtained in step S3 to remove the oxide scale on the surface of the alloy steel; use clean water to rinse and dry the polished surface of the alloy steel, soak the dried alloy steel in a 48wt% nitric acid solution, the temperature of the nitric acid solution is 42°C, soak for 32 minutes, take out the alloy steel and soak it in an ultrasonic device filled with clean water, ultrasonically clean and dry the alloy steel, the ultrasonic power is 950W, and the ultrasonic cleaning time is 22 minutes;

[0261] The alloy steel after ultrasonic cleaning was preheated to 58°C, and the surface of the dried alloy steel was sandblasted with white corundum with a particle size of 2.5 mm. The sandblasting pressure was 0.52 MPa, the sandblasting distance was 130 mm, the angle between the nozzle axis and the surface of the alloy steel was 68°, and the sandblasting time was 6 min. After the sandblasting, the alloy steel was cleaned and dried;

[0262] The sandblasted alloy steel is immersed in a passivation solution at 68° C. for surface passivation treatment, wherein the mass fraction of citric acid in the passivation solution is 22wt%, and the mass fraction of ethylenediaminetetraacetic acid is 1.2wt%; after immersion for 22 minutes, the alloy steel is cleaned and dried to obtain a sandblasted steel;

[0263] S5, laser cladding: 58 parts of aluminum powder, 20 parts of tungsten carbide powder, 9 parts of nickel powder, 8 parts of cubic boron nitride powder, 4 parts of titanium dioxide powder and 1 part of cerium dioxide powder are mixed and ball-milled to obtain a cladding material; the cladding material is mixed with a binder solution at a ratio of 1 g:0.28 mL to obtain a paste-like cladding slurry; wherein the binder solution is composed of anhydrous ethanol and polyvinyl alcohol in a mass ratio of 18:1;

[0264] The cladding slurry is uniformly coated on the surface of the sandblasted steel obtained in step S4, the coating thickness of the cladding slurry is 1.8 mm, and a cladding slurry layer is formed after drying; the sandblasted steel with the cladding slurry layer is placed in a cladding device, argon gas is introduced into the cavity of the cladding device, and the argon gas flow rate is 14 L / min. In the argon atmosphere, a laser is used to perform laser cladding on the cladding slurry layer, the laser power is set to 3.8 kW, the spot diameter is set to 4.5 mm, and the scanning speed is set to 160 mm / min. After cooling, a cladding layer is formed on the surface of the sandblasted steel, and a cladding steel consisting of a cladding layer and a sandblasted steel is obtained;

[0265] S6, nitriding treatment: nickel sulfate, sodium citrate, sodium acetate, thiourea, potassium iodide, succinic acid, sodium dodecyl sulfate, sodium hypophosphite, alumina sol and deionized water are mixed to obtain a nickel plating solution, wherein the concentration of nickel sulfate in the nickel plating solution is 32 g / L, the concentration of sodium citrate is 18 g / L, the concentration of sodium acetate is 22 g / L, the concentration of thiourea is 0.4 mg / L, the concentration of potassium iodide is 4 mg / L, the concentration of succinic acid is 22 g / L, the concentration of sodium dodecyl sulfate is 0.5 g / L, the concentration of sodium hypophosphite is 22 g / L, and the concentration of alumina sol is 22 mL / L;

[0266] The prepared nickel plating solution is poured into a constant temperature water bath, and the nickel plating solution is heated and stirred. The heating temperature of the nickel plating solution is 58°C and the stirring speed is 13r / min. The clad steel and nickel plate obtained in step S5 are immersed in the prepared nickel plating solution and are electrically connected to the negative electrode and the positive electrode of the dual pulse power supply respectively. The waveform of the pulse current output by the dual pulse power supply is square, the width of the positive pulse is 58ms, the duty cycle is 58%, and the current density is 3.2A / dm 2 ; The width of the negative pulse is 18ms, the duty cycle is 18%, and the current density is 1.4A / dm 2; Electrochemically depositing the cladding steel for 15 minutes to form a composite nickel coating with a thickness of 16 μm on the surface of the cladding steel to obtain a nickel-plated steel;

[0267] The nickel-plated steel is placed in a heat treatment device, ammonia gas is introduced into the cavity of the heat treatment device, and the flow rate of ammonia gas is 9.5 L / min. The nickel-plated steel is heated to 380° C. and kept warm for 8.5 hours to perform nitriding treatment to obtain a composite steel;

[0268] S7, micro-arc oxidation: immerse the composite steel and stainless steel plate obtained in step S6 in an electrolyte at 58°C and electrically connect them to the positive and negative electrodes of a power source, respectively. The concentration of sodium silicate in the electrolyte is 28 g / L, the concentration of sodium nitrate is 12 g / L, the concentration of sodium fluoride is 4 g / L, the concentration of potassium hydroxide is 4 g / L, and the concentration of calcium acetate is 8 g / L; the current density of the pulse current output by the power source is 7.5 A / dm 2 , the duty cycle is 28%; the composite steel is used as the anode and the stainless steel plate is used as the cathode, and the cladding layer on the surface of the composite steel is subjected to micro-arc oxidation treatment for 8 minutes to form a micro-arc oxidation layer with a porous structure on the surface of the cladding layer;

[0269] The silane coupling agent KH560 is added to an ethanol aqueous solution (the volume ratio of ethanol to deionized water is 7:3), and the mixture is mixed and stirred for 2.8 hours to obtain a 1.8wt% coupling agent solution. Glacial acetic acid is added dropwise to the coupling agent solution to adjust its pH value to 3.8; the composite steel obtained after micro-arc oxidation treatment is immersed in the prepared coupling agent solution, and after soaking in the coupling agent solution for 1.2 hours, the composite steel is taken out, cleaned and dried to obtain the corrosion-resistant high-temperature steel composite material.

[0270] Example 5

[0271] This embodiment provides a method for preparing a corrosion-resistant high-temperature steel composite material. Figure 1 As shown, the preparation method specifically comprises the following steps:

[0272] S1. Smelting and refining: pure iron is put into a smelting furnace for heating and smelting to form molten iron, the heating and smelting temperature is 1650° C., and the holding time is 4 hours; then, the molten iron is transferred to an LF refining furnace and the temperature of the molten iron is adjusted to 1750° C., molybdenum-iron alloy, chromium-iron alloy, manganese-iron alloy and silicon-iron alloy are added to the molten iron in sequence, and argon gas is blown into the bottom of the molten iron at a flow rate of 400 L / min for stirring, and the argon is blown and stirred for 30 minutes and then kept warm for 20 minutes to obtain alloy steel liquid;

[0273] Desulfurizer and dephosphorizer were added to the alloy steel liquid, and argon was blown in from the bottom of the alloy steel liquid at a flow rate of 600 L / min for stirring. The desulfurizer consisted of lime, fluorite powder and aluminum powder, and 10 kg of lime, 1 kg of fluorite powder and 1 kg of aluminum powder were added to each ton of alloy steel liquid. The dephosphorizer consisted of lime and bauxite, and 9 kg of lime and 1.5 kg of bauxite were added to each ton of alloy steel liquid. After argon blowing and stirring for 5 minutes, the mixture was kept warm for 20 minutes. After the heat preservation was completed, the alloy steel was The molten steel was transferred to a VD vacuum furnace and evacuated to 60 Pa and maintained at this pressure for 20 min, and then argon was blown into the molten steel from the bottom at a flow rate of 5 L / min and continued to blow argon for 10 min to obtain a refined molten steel. The mass fraction of each element in the refined molten steel was controlled within the following ranges: 0.02 wt% carbon, 2.5 wt% molybdenum, 16 wt% chromium, 1.5 wt% manganese, 0.5 wt% silicon, 0.003 wt% sulfur and 0.05 wt% phosphorus, and the remainder was iron;

[0274] S2, casting: the refined molten steel obtained in step S1 is injected into a casting device for vacuum casting, such as Figure 2 As shown, the casting equipment includes a vacuum chamber 3, a steel ingot mold 4 and a tundish 1. The steel ingot mold 4 is located inside the vacuum chamber 3, the tundish 1 is located on the top of the vacuum chamber 3, and a liquid outlet 2 is provided at the bottom of the tundish 1. The tundish 1 is connected to the steel ingot mold 4 through the liquid outlet 2, and the liquid outlet 2 is externally connected to an argon gas source 5;

[0275] The vacuum casting process includes: preheating the steel ingot mold 4 to 250°C, adjusting the temperature of the refined steel liquid obtained in step S1 to 1530°C, and then injecting it into the tundish 1 at a speed of 8t / min, and the argon gas source 5 introduces argon gas to the liquid outlet 2 at a flow rate of 8L / min, and the refined steel liquid is mixed with the argon gas when flowing through the liquid outlet 2 and then flows into the preheated steel ingot mold 4, and after the refined steel liquid is completely injected into the steel ingot mold 4, it is naturally cooled to room temperature, and the alloy steel casting is obtained after demolding;

[0276] S3, quenching and tempering heat treatment: the alloy steel casting obtained in step S2 is heated to 950°C at a heating rate of 100°C / h, and kept at this temperature for 2h. After the insulation, the primary annealing treatment is completed; then, the alloy steel casting after the primary annealing treatment is cooled to 700°C with the furnace, and kept at this temperature for 4h. After the insulation, the alloy steel casting is taken out of the furnace and air-cooled to room temperature to complete the secondary annealing treatment;

[0277] The alloy steel casting after the secondary annealing treatment is heated to 900°C at a heating rate of 70°C / h, and kept at this temperature for 50 minutes. After the insulation, the alloy steel casting is taken out of the furnace and immediately immersed in cooling water at 30°C for 60 minutes to achieve rapid cooling of the alloy steel casting. The cooling rate of the alloy steel casting in the cooling water is 150°C / h, and the quenching treatment is completed. After the quenching treatment, the alloy steel material is obtained;

[0278] S4, sandblasting roughening: use 500-mesh fine sandpaper to grind the surface of the alloy steel obtained in step S3 to remove the oxide scale on the surface of the alloy steel; use clean water to rinse and dry the polished surface of the alloy steel, and soak the dried alloy steel in a 50wt% hydrochloric acid solution at a temperature of 40°C. After soaking for 30 minutes, take out the alloy steel and soak it in an ultrasonic device filled with clean water, and ultrasonically clean and dry the alloy steel, the ultrasonic power is 1000W, and the ultrasonic cleaning time is 20 minutes;

[0279] The alloy steel after ultrasonic cleaning was preheated to 60°C, and the surface of the dried alloy steel was sandblasted with white corundum with a particle size of 3 mm. The sandblasting pressure was 0.5 MPa, the sandblasting distance was 150 mm, the angle between the nozzle axis and the surface of the alloy steel was 70°, and the sandblasting time was 8 min. After the sandblasting, the alloy steel was cleaned and dried.

[0280] The sandblasted alloy steel is immersed in a passivation solution at 70° C. for surface passivation treatment, wherein the mass fraction of citric acid in the passivation solution is 25wt%, and the mass fraction of ethylenediaminetetraacetic acid is 1.5wt%; after immersion for 20 minutes, the alloy steel is cleaned and dried to obtain a sandblasted steel;

[0281] S5, laser cladding: 60 parts of aluminum powder, 20 parts of tungsten carbide powder, 8.2 parts of nickel powder, 8 parts of cubic boron nitride powder, 3 parts of titanium dioxide powder and 0.8 parts of cerium dioxide powder are mixed and ball-milled to obtain a cladding material; the cladding material is mixed with a binder solution at a ratio of 1 g:0.3 mL to obtain a paste-like cladding slurry; wherein the binder solution is composed of anhydrous ethanol and polyvinyl alcohol in a mass ratio of 20:1;

[0282] The cladding slurry is uniformly coated on the surface of the sandblasted steel obtained in step S4, the coating thickness of the cladding slurry is 2 mm, and a cladding slurry layer is formed after drying; the sandblasted steel with the cladding slurry layer is placed in a cladding device, argon gas is introduced into the cavity of the cladding device, and the argon gas flow rate is 15 L / min. In the argon atmosphere, a laser is used to perform laser cladding on the cladding slurry layer, the laser power is set to 4 kW, the spot diameter is set to 5 mm, and the scanning speed is set to 150 mm / min. After cooling, a cladding layer is formed on the surface of the sandblasted steel, and a cladding steel consisting of a cladding layer and a sandblasted steel is obtained;

[0283] S6, nitriding treatment: nickel sulfate, sodium citrate, sodium acetate, thiourea, potassium iodide, succinic acid, sodium dodecyl sulfate, sodium hypophosphite, alumina sol and deionized water are mixed to obtain a nickel plating solution, wherein the concentration of nickel sulfate in the nickel plating solution is 35 g / L, the concentration of sodium citrate is 15 g / L, the concentration of sodium acetate is 25 g / L, the concentration of thiourea is 0.5 mg / L, the concentration of potassium iodide is 5 mg / L, the concentration of succinic acid is 25 g / L, the concentration of sodium dodecyl sulfate is 0.6 g / L, the concentration of sodium hypophosphite is 20 g / L, and the concentration of alumina sol is 25 mL / L;

[0284] The prepared nickel plating solution is poured into a constant temperature water bath, and the nickel plating solution is heated and stirred. The heating temperature of the nickel plating solution is 60°C and the stirring speed is 15r / min. The cladding steel and nickel plate obtained in step S5 are immersed in the prepared nickel plating solution and are electrically connected to the negative electrode and the positive electrode of the dual pulse power supply respectively. The waveform of the pulse current output by the dual pulse power supply is square, the width of the positive pulse is 60ms, the duty cycle is 60%, and the current density is 3.5A / dm 2 ; The width of the negative pulse is 20ms, the duty cycle is 20%, and the current density is 1.5A / dm 2 ; Electrochemically depositing the cladding steel for 10 minutes to form a composite nickel coating with a thickness of 15 μm on the surface of the cladding steel to obtain a nickel-plated steel;

[0285] The nickel-plated steel is placed in a heat treatment device, ammonia gas is introduced into the cavity of the heat treatment device, and the flow rate of ammonia gas is 10 L / min. The nickel-plated steel is heated to 400° C. and kept warm for 8 hours to perform nitriding treatment to obtain a composite steel;

[0286] S7, micro-arc oxidation: immerse the composite steel and stainless steel plate obtained in step S6 in an electrolyte at 60°C and electrically connect them to the positive and negative electrodes of a power source, respectively. The concentration of sodium silicate in the electrolyte is 30 g / L, the concentration of sodium nitrate is 10 g / L, the concentration of sodium fluoride is 5 g / L, the concentration of potassium hydroxide is 3 g / L, and the concentration of calcium acetate is 5 g / L; the current density of the pulse current output by the power source is 8 A / dm 2 , the duty cycle is 30%; using the composite steel as the anode and the stainless steel plate as the cathode, the cladding layer on the surface of the composite steel is subjected to micro-arc oxidation treatment for 5 minutes to form a micro-arc oxidation layer with a porous structure on the surface of the cladding layer;

[0287] The silane coupling agent KH570 is added to an ethanol aqueous solution (the volume ratio of ethanol to deionized water is 7:3), and the mixture is stirred for 3 hours to obtain a 2wt% coupling agent solution. Glacial acetic acid is added dropwise to the coupling agent solution to adjust its pH value to 4. The composite steel obtained after micro-arc oxidation treatment is immersed in the prepared coupling agent solution, and after soaking in the coupling agent solution for 1 hour, the composite steel is taken out, cleaned and dried to obtain the corrosion-resistant high-temperature steel composite material.

[0288] Comparative Example 1

[0289] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material, which is different from Example 1 in that in step S4, the sandblasting time is adjusted to 1 min, and other process parameters and operation steps are exactly the same as those in Example 1.

[0290] Comparative Example 2

[0291] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material. The difference from Example 1 is that in step S4, the sandblasting time is adjusted to 10 minutes, and the other process parameters and operation steps are exactly the same as those in Example 1.

[0292] Comparative Example 3

[0293] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material. The difference from Example 1 is that in step S6, the concentration of alumina sol in the nickel plating solution is adjusted to 10 mL / L, and other process parameters and operating steps are exactly the same as those in Example 1.

[0294] Comparative Example 4

[0295] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material. The difference from Example 1 is that in step S6, the concentration of alumina sol in the nickel plating solution is adjusted to 30 mL / L, and other process parameters and operating steps are exactly the same as those in Example 1.

[0296] The cross-sectional microstructures of the corrosion-resistant high-temperature steel composite materials prepared in Example 1, Comparative Example 3 and Comparative Example 4 were observed by scanning electron microscope, and the following results were obtained: Figure 3 (Example 1), Figure 4 (Comparative Example 3) and Figure 5 The cross-sectional SEM image shown in (Comparative Example 4) is Figure 3 , Figure 4 and Figure 5 By comparison, it can be seen that Figure 3 , Figure 4 and Figure 5 The matrix, nitriding layer and micro-arc oxidation layer can be clearly seen in the Figure 3The thickness of the nitriding layer in is the largest. This is because in Example 1, alumina sol of appropriate concentration is added to the nickel plating solution, which promotes the penetration and diffusion of active nitrogen atoms and is beneficial to the increase of the thickness of the nitriding layer.

[0297] Comparative Example 5

[0298] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material. The difference from Example 1 is that in step S6, the duty cycle of the positive pulse output by the dual-pulse power supply is adjusted to 45%, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0299] Comparative Example 6

[0300] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material. The difference from Example 1 is that in step S6, the duty cycle of the positive pulse output by the dual-pulse power supply is adjusted to 65%, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0301] Comparative Example 7

[0302] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material. The difference from Example 1 is that in step S6, the current density of the positive pulse output by the dual-pulse power supply is adjusted to 2A / dm 2 , other process parameters and operation steps are exactly the same as those in Example 1.

[0303] Comparative Example 8

[0304] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material. The difference from Example 1 is that in step S6, the current density of the positive pulse output by the dual-pulse power supply is adjusted to 4A / dm 2 , other process parameters and operation steps are exactly the same as those in Example 1.

[0305] Comparative Example 9

[0306] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material. The difference from Example 1 is that the electrochemical deposition treatment in step S6 is omitted, and the cladding steel obtained in step S5 is directly placed in a heat treatment device for nitriding treatment. The other process parameters and operating steps are exactly the same as those in Example 1.

[0307] Comparative Example 10

[0308] This comparative example provides a method for preparing a corrosion-resistant high-temperature steel composite material. The difference from Example 1 is that step S4, step S5, step S6 and step S7 are omitted, and no surface treatment is performed on the alloy steel obtained in step S3. Other process parameters and operating steps are exactly the same as those in Example 1.

[0309] The corrosion-resistant high-temperature steel composite materials prepared in Example 1, Comparative Example 9 and Comparative Example 10 were subjected to friction tests, and the wear marks after the friction tests were observed using a scanning electron microscope. Fig. 9 (Example 1), Fig.10 (Comparative Example 9) and Fig.11 The scanning electron microscope image of the wear scar surface shown in (Comparative Example 10), wherein: Fig. 9 The wear scar width shown is about 160 μm. Fig.10 The wear scar width shown is about 240 μm. Fig.11 The width of the wear scar is about 510 μm, from which it can be seen that the corrosion-resistant high-temperature steel composite material prepared by the preparation method provided by the present invention has excellent wear resistance.

[0310] The wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite materials prepared in Examples 1-5 and Comparative Examples 1-10 were tested, and the specific test steps are as follows:

[0311] (1) Wear resistance

[0312] A microcomputer-controlled reciprocating friction and wear testing machine was used to carry out friction and wear tests on the corrosion-resistant high-temperature steel composite materials prepared in Examples 1-5 and Comparative Examples 1-10. Silicon nitride balls with a diameter of 5 mm were selected for the grinding pair, the friction load was set to 5 N, the reciprocating stroke was set to 20 mm, and the reciprocating frequency was set to 20 r / min. A high-precision analytical balance (with an accuracy of 0.01 mg) was used to weigh the mass change of the sample before and after the friction and wear test, and the difference was taken as the wear amount (mg) of the sample. The wear resistance of the corrosion-resistant high-temperature steel composite material was evaluated by the wear amount. The lower the wear amount, the better the wear resistance of the corrosion-resistant high-temperature steel composite material.

[0313] (2) Corrosion resistance

[0314] An electrochemical workstation was used to perform electrochemical tests on the corrosion-resistant high-temperature steel composite materials prepared in Examples 1-5 and Comparative Examples 1-10. The electrochemical test adopted a three-electrode system, with a 232-type saturated calomel electrode (SCE) as a reference electrode, a platinum mesh electrode as a counter electrode, and a sample with an area of ​​0.5×0.5 cm as a working electrode. The potential value relative to the reference electrode was used as the measured potential. A constant temperature water bath was used for water bath heating to ensure that the electrochemical test process was carried out at a constant temperature of 25°C, and a 3.5wt% NaCl solution was used as the experimental medium.

[0315] During the electrochemical test, the potentiodynamic polarization curve of the sample was measured. The scanning range was 500mV below the open circuit voltage to 1.0V, and the scanning speed was 30mV / min. The corrosion potential (mV) and corrosion current density (μA / cm 2 ), the corrosion resistance of the corrosion-resistant high-temperature steel composite material was evaluated by the size of the corrosion potential and the corrosion current density. The higher the corrosion potential and the lower the corrosion current density, the better the corrosion resistance of the corrosion-resistant high-temperature steel composite material.

[0316] The test results are shown in Table 1.

[0317] Table 1 Test data of corrosion-resistant high-temperature steel composite materials prepared in Examples 1-5 and Comparative Examples 1-10

[0318]

[0319]

[0320] It can be seen from the test data provided in Table 1 that the wear amount of the corrosion-resistant high-temperature steel composite materials prepared in Examples 1-5 is significantly lower than that in Comparative Examples 1-10, which indicates that the corrosion-resistant high-temperature steel composite materials prepared in the present invention have excellent wear resistance; in addition, the corrosion potential of the corrosion-resistant high-temperature steel composite materials prepared in Examples 1-5 is significantly higher than that in Comparative Examples 1-10, and the corrosion current density is significantly lower than that in Comparative Examples 1-10, which indicates that the corrosion-resistant high-temperature steel composite materials prepared in the present invention have excellent corrosion resistance.

[0321] It can be seen from the test data of Example 1, Comparative Example 1 and Comparative Example 2 that the wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite materials prepared in Comparative Example 1 and Comparative Example 2 are inferior to those in Example 1. This is because the sandblasting time in Comparative Example 1 is too short, while the sandblasting time in Comparative Example 2 is too long, indicating that too short or too long sandblasting time will affect the wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite materials.

[0322] It can be seen from the test data of Example 1, Comparative Example 3 and Comparative Example 4 that the wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite materials prepared in Comparative Example 3 and Comparative Example 4 are inferior to those in Example 1. This is because the concentration of the alumina sol in Comparative Example 3 is too low, while the concentration of the alumina sol in Comparative Example 4 is too high, indicating that too low or too high alumina sol concentration will affect the wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite material.

[0323] It can be seen from the test data of Example 1, Comparative Example 5 and Comparative Example 6 that the wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite materials prepared in Comparative Example 5 and Comparative Example 6 are inferior to those in Example 1. This is because the duty cycle of the positive pulse in Comparative Example 5 is too low, while the duty cycle of the positive pulse in Comparative Example 6 is too high, indicating that a duty cycle of the positive pulse that is too low or too high will affect the wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite material.

[0324] It can be seen from the test data of Example 1, Comparative Example 7 and Comparative Example 8 that the wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite materials prepared in Comparative Example 7 and Comparative Example 8 are inferior to those in Example 1. This is because the current density of the positive pulse in Comparative Example 7 is too low, while the current density of the positive pulse in Comparative Example 8 is too high, indicating that too low or too high current density of the positive pulse will affect the wear resistance and corrosion resistance of the corrosion-resistant high-temperature steel composite material.

[0325] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a corrosion-resistant high-temperature steel composite material, characterized in that: The preparation method comprises: Using pure iron, ferromolybdenum alloy, ferrochrome alloy, ferromanganese alloy and ferrosilicon alloy as raw materials, successively undergoing smelting and refining, casting and tempering heat treatment to obtain alloy steel, and roughening the surface of the alloy steel by sandblasting to form a roughened surface to obtain sandblasted steel; Laser cladding is performed on the roughened surface of the alloy steel material, and the laser cladding process includes: Aluminum powder, tungsten carbide powder, nickel powder, cubic boron nitride powder, titanium dioxide powder and cerium dioxide powder are mixed and ball-milled to obtain a cladding material; the cladding material is mixed with a binder solution to obtain a paste-like cladding slurry; the cladding slurry is evenly coated on the roughened surface of the sandblasted steel material, and a cladding slurry layer is formed after drying; the sandblasted steel material with the cladding slurry layer formed thereon is placed in a cladding device, argon gas is introduced into the cavity of the cladding device, and the cladding slurry layer is laser clad by a laser in an argon atmosphere, and a cladding layer is formed on the surface of the sandblasted steel material after cooling, so as to obtain a cladding steel material composed of the cladding layer and the sandblasted steel material; After the laser cladding is completed, the cladding layer of the cladding steel material is subjected to nitriding treatment and micro-arc oxidation treatment in sequence to obtain the corrosion-resistant high-temperature steel composite material.

2. The preparation method according to claim 1, characterized in that: Taking the weight of the cladding material as 100 parts, it includes the following components in parts by weight: The binder solution consists of anhydrous ethanol and polyvinyl alcohol; The mass ratio of the anhydrous ethanol to the polyvinyl alcohol is (10-20):1; The ratio of the cladding material to the binder solution is 1 g: (0.2-0.3) mL; The coating thickness of the cladding slurry is 1 to 2 mm; The argon gas flow rate is 8 to 15 L / min; The laser power emitted by the laser is 3-4 kW; The laser spot emitted by the laser has a diameter of 3 to 5 mm; The scanning speed of the laser emitted by the laser is 150-200 mm / min.

3. The preparation method according to claim 1, characterized in that: The specific steps of the smelting and refining process include: Put pure iron into a smelting furnace and heat it to form molten iron, transfer the molten iron to an LF refining furnace and adjust the temperature of the molten iron to a refining temperature, then sequentially add ferromolybdenum alloy, ferrochrome alloy, ferromanganese alloy and ferrosilicon alloy to the molten iron, and simultaneously blow argon gas from the bottom of the molten iron to stir it, and after the stirring is completed, perform a first heat preservation, and after the first heat preservation is completed, obtain alloy steel liquid; add a desulfurizer and a dephosphorization agent to the alloy steel liquid, and simultaneously blow argon gas from the bottom of the alloy steel liquid to stir it, and after the stirring is completed, perform a second heat preservation, and after the second heat preservation is completed, transfer the alloy steel liquid to a VD vacuum furnace for vacuuming and pressure maintenance, and then blow argon gas from the bottom of the alloy steel liquid to obtain refined steel liquid; The heating and melting temperature is 1580-1650°C; The holding time of the heating and smelting is 4 to 5 hours; The refining temperature is 1650-1750°C; While adding the ferromolybdenum alloy, the ferrochrome alloy, the ferromanganese alloy and the ferrosilicon alloy, the flow rate of argon gas into the iron melt is 300-400 L / min; The time for passing argon gas into the iron melt while adding the molybdenum iron alloy, the chromium iron alloy, the manganese iron alloy and the silicon iron alloy is 30 to 40 minutes; The first insulation time is 10 to 20 minutes; The desulfurizer is composed of lime, fluorite powder and aluminum powder, wherein 8-10 kg of lime, 1-2 kg of fluorite powder and 0.5-1 kg of aluminum powder are added to each ton of alloy steel liquid; The dephosphorization agent is composed of lime and bauxite, wherein 7-9 kg of lime and 1.5-2.5 kg of bauxite are added to each ton of alloy steel liquid; The flow rate of argon gas introduced into the alloy steel liquid while adding the desulfurizer and the dephosphorizer is 500-600 L / min; the time of introducing argon gas into the alloy steel liquid while adding the desulfurizer and the dephosphorizer is 3-5 min; The second insulation time is 10 to 20 minutes; The vacuum degree of the alloy steel liquid in the VD vacuum furnace is 50-60 Pa; The pressure holding time of the alloy steel liquid in the VD vacuum furnace is 20 to 30 minutes; The flow rate of argon gas introduced into the alloy steel liquid after evacuation is 3-5 L / min; The time for passing argon gas into the alloy steel liquid after evacuation is 10 to 20 minutes; Taking the mass fraction of the refined steel liquid as 100wt%, the mass fraction of each element in the refined steel liquid is controlled within the following range: Carbon 0.01-0.02wt%, molybdenum 2.0-2.5wt%, chromium 16-17wt%, manganese 1.2-1.5wt%, silicon 0.5-0.6wt%, sulfur 0.001-0.003wt% and phosphorus 0.01-0.05wt%, and the balance is iron.

4. The preparation method according to claim 3, characterized in that: The specific steps of the casting process include: The refined molten steel obtained by smelting and refining is injected into a casting device for vacuum casting, wherein the casting device comprises a vacuum chamber, an ingot mold and a tundish, wherein the ingot mold is located inside the vacuum chamber, the tundish is located at the top of the vacuum chamber, and a liquid outlet is provided at the bottom of the tundish, wherein the tundish is connected to the ingot mold through the liquid outlet, and the liquid outlet is externally connected to an argon gas source; the temperature of the refined molten steel is adjusted to the casting temperature and then injected into the tundish, wherein the argon gas source introduces argon gas into the liquid outlet, and the refined molten steel is mixed with argon gas when flowing through the liquid outlet and then flows into the ingot mold, and after the refined molten steel is completely injected into the ingot mold, it is naturally cooled to room temperature, and an alloy steel casting is obtained after demoulding; The casting temperature of the refined steel liquid is 1520-1530°C; Before casting the refined molten steel, the ingot mold is preheated to 200-250°C; The speed at which the refined steel liquid is injected into the tundish is 3-8 t / min; The flow rate of the argon gas entering the liquid outlet is 5 to 8 L / min.

5. The preparation method according to claim 4, characterized in that: The specific steps of the quenching and tempering heat treatment process include: The alloy steel casting obtained by casting is heated to a first annealing temperature, kept warm at the first annealing temperature, and a primary annealing treatment is completed after the insulation is completed; then, the alloy steel casting after the primary annealing treatment is cooled with the furnace to a second annealing temperature, kept warm at the second annealing temperature, and after the insulation is completed, the alloy steel casting is taken out of the furnace and air-cooled to room temperature to complete a secondary annealing treatment; the alloy steel casting after the secondary annealing treatment is heated to a quenching temperature, kept warm at the quenching temperature, and after the insulation is completed, the alloy steel casting is taken out of the furnace and immediately immersed in cooling water for rapid cooling to complete the quenching treatment, and an alloy steel material is obtained after the quenching treatment is completed; The alloy steel casting is heated to a first annealing temperature at a heating rate of 80 to 100° C. / h; The first annealing temperature is 900-950° C.; Keeping the temperature at the first annealing temperature for 2 to 3 hours; The second annealing temperature is 680-700° C.; Keeping the temperature at the second annealing temperature for 4 to 5 hours; The alloy steel casting after the secondary annealing treatment is heated to the quenching temperature at a heating rate of 60 to 70° C. / h; The quenching temperature is 850-900°C; Keeping the quenching temperature at 50 to 60 minutes; The temperature of the cooling water is 10-30°C; The cooling rate of the alloy steel casting in the cooling water is 150-160°C / h; The alloy steel casting is immersed in the cooling water for 60 to 90 minutes.

6. The preparation method according to claim 5, characterized in that: The specific steps of the sandblasting roughening process include: The surface of the alloy steel obtained by the quenching and tempering heat treatment is polished with fine sandpaper to remove the oxide scale on the surface of the alloy steel; the polished surface of the alloy steel is rinsed with clean water and dried, and the dried alloy steel is immersed in a pickling solution. After the immersion, the alloy steel is taken out and immersed in an ultrasonic device filled with clean water, and the alloy steel is ultrasonically cleaned and dried; the surface of the dried alloy steel is sandblasted, and the alloy steel is cleaned and dried after the sandblasting is completed; the alloy steel is immersed in a passivation solution for surface passivation treatment, and the alloy steel is cleaned and dried after the passivation is completed to obtain a sandblasted steel; The mesh number of the fine sandpaper is 400 to 500 meshes; The pickling solution is a nitric acid solution, a sulfuric acid solution or a hydrochloric acid solution; The mass fraction of the pickling solution is 40 to 50 wt %; The temperature of the pickling solution is 40-50°C; The alloy steel is immersed in the pickling solution for 30 to 40 minutes; The ultrasonic power of the ultrasonic device is 800-1000W; The ultrasonic cleaning time is 20 to 30 minutes; Before the sandblasting treatment, the alloy steel is preheated to 50-60°C; The sandblasting medium used in the sandblasting process is white corundum; The particle size of the sandblasting medium used in the sandblasting treatment is 1 to 3 mm; The blasting pressure of the blasting treatment is 0.5-0.6 MPa; During the sandblasting process, the sandblasting distance between the nozzle and the surface of the alloy steel material is 100 to 150 mm; During the sandblasting process, the angle between the nozzle axis and the surface of the alloy steel material is 60-70°; The sandblasting time is 3 to 8 minutes; The passivation solution consists of citric acid, ethylenediaminetetraacetic acid and deionized water; The mass fraction of citric acid in the passivation solution is 15-25wt%; The mass fraction of ethylenediaminetetraacetic acid in the passivation solution is 0.5-1.5wt%; The temperature of the passivation solution is 60-70°C; The alloy steel material is immersed in the passivation solution for 20 to 30 minutes.

7. The preparation method according to claim 6, characterized in that: The nitriding process specifically comprises the following steps: Nickel sulfate, sodium citrate, sodium acetate, thiourea, potassium iodide, succinic acid, sodium dodecyl sulfate, sodium hypophosphite, alumina sol and deionized water are mixed to obtain a nickel plating solution, the nickel plating solution is poured into a constant temperature water bath, and the nickel plating solution is heated and stirred; the cladding steel and the nickel plate obtained by laser cladding are immersed in the nickel plating solution and are electrically connected to the negative electrode and the positive electrode of a double pulse power supply respectively, and the cladding steel is electrochemically deposited to form a composite nickel coating on the surface of the cladding steel to obtain a nickel-plated steel; the nickel-plated steel is placed in a heat treatment device, ammonia is introduced into the cavity of the heat treatment device, and the nickel-plated steel is heated to a nitriding temperature and kept warm to perform a nitriding treatment to obtain a composite steel; The concentration of nickel sulfate in the nickel plating solution is 25-35 g / L; The concentration of sodium citrate in the nickel plating solution is 15-25 g / L; The concentration of sodium acetate in the nickel plating solution is 15-25 g / L; The concentration of thiourea in the nickel plating solution is 0.1-0.5 mg / L; The concentration of potassium iodide in the nickel plating solution is 1-5 mg / L; The concentration of succinic acid in the nickel plating solution is 15-25 g / L; The concentration of sodium dodecyl sulfate in the nickel plating solution is 0.2-0.6 g / L; The concentration of sodium hypophosphite in the nickel plating solution is 20-30 g / L; The concentration of the aluminum oxide sol in the nickel plating solution is 15 to 25 mL / L; The heating temperature of the nickel plating solution is 50-60°C; The stirring speed of the nickel plating solution is 10-15 r / min; The waveform of the pulse current output by the double-pulse power supply is square; The width of the positive pulse output by the double pulse power supply is 50-60ms; The duty cycle of the positive pulse output by the double-pulse power supply is 50-60%; The current density of the positive pulse output by the double pulse power supply is 2.5-3.5A / dm 2 ; The width of the negative pulse output by the double pulse power supply is 10 to 20 ms; The duty cycle of the negative pulse output by the double pulse power supply is 10-20%; The current density of the negative pulse output by the double pulse power supply is 1.2-1.5A / dm 2 ; The electrochemical deposition time is 10 to 30 minutes; The thickness of the composite nickel plating layer is 15 to 20 μm; The nitriding temperature is 350-400°C; The ammonia gas flow rate is 8-10 L / min; The holding time of the nitriding treatment is 8 to 10 hours.

8. The preparation method according to claim 7, characterized in that: The micro-arc oxidation treatment process specifically comprises the following steps: The composite steel and the stainless steel plate obtained by the nitriding treatment are immersed in an electrolyte and electrically connected to the positive electrode and the negative electrode of the power supply respectively, the composite steel is used as an anode and the stainless steel plate is used as a cathode, and the cladding layer on the surface of the composite steel is subjected to micro-arc oxidation treatment to form a micro-arc oxidation layer with a porous structure on the surface of the cladding layer; Adding a silane coupling agent to an ethanol aqueous solution and mixing them evenly to obtain a coupling agent solution, dropping glacial acetic acid into the coupling agent solution to adjust the pH value thereof to acidic, immersing the composite steel material after micro-arc oxidation treatment into the coupling agent solution, and after immersion, taking out the composite steel material, washing and drying it to obtain the corrosion-resistant high-temperature steel composite material; The electrolyte consists of sodium silicate, sodium nitrate, sodium fluoride, potassium hydroxide, calcium acetate and deionized water; The concentration of sodium silicate in the electrolyte is 20-30 g / L; The concentration of sodium nitrate in the electrolyte is 10-20 g / L; The concentration of sodium fluoride in the electrolyte is 1 to 5 g / L; The concentration of potassium hydroxide in the electrolyte is 3 to 8 g / L; The concentration of calcium acetate in the electrolyte is 5 to 15 g / L; The temperature of the electrolyte is 50-60°C; The current density of the pulse current output by the power supply is 6-8A / dm 2 ; The duty cycle of the pulse current output by the power supply is 20-30%; The micro-arc oxidation treatment time is 5 to 15 minutes; The silane coupling agent and the ethanol aqueous solution are mixed and stirred for 2 to 3 hours; The mass fraction of the silane coupling agent in the coupling agent solution is 1-2wt%; Add glacial acetic acid dropwise to the coupling agent solution to adjust the pH value thereof to 3-4; The composite steel material is immersed in the coupling agent solution for 1 to 2 hours.

9. A corrosion-resistant high-temperature steel composite material prepared by the preparation method according to any one of claims 1 to 8.

10. An application of the corrosion-resistant high-temperature steel composite material according to claim 9, characterized in that: The corrosion-resistant and high-temperature steel composite material is used for preparing steel for corrosion-resistant and high-temperature resistant parts.

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