A method for preparing nickel-chromium plated steel strip

Abstract

The invention discloses a method for preparing a nickel-chromium plated steel strip. In the scheme, a stainless steel strip is plated with nickel-chromium to form a nickel-chromium-phosphorus ternary coating. The surface coating can effectively improve the surface corrosion resistance of the stainless steel strip. After the nickel-chromium coating, the invention further performs a gas nitriding treatment to improve the surface hardness and wear resistance of the stainless steel strip. The presence of the nickel-chromium plated transition layer can promote the adsorption and decomposition of ammonia and the transfer of active nitrogen atoms during the nitriding process, thereby improving the nitriding effect of the stainless steel strip surface. The process parameters of each step of the scheme are reasonable, the component ratio is appropriate, the prepared steel strip has excellent corrosion resistance, and its surface wear resistance and hardness are greatly improved. The steel strip can be widely applied to multiple fields and has high practicality.

Description

Technical Field

[0001] The invention relates to the technical field of stainless steel strips, in particular to a method for preparing a nickel-chromium plated steel strip. Background Art

[0002] Stainless steel strip, to put it simply, is an extension of ultra-thin stainless steel plate. It is a narrow and long steel plate mainly produced to meet the needs of industrial production of various metal or mechanical products in different industrial sectors. With the development and progress of science and technology, enterprises have begun to conduct more and more in-depth research on the performance of stainless steel strips. However, the hardness and corrosion resistance of the stainless steel strips currently on the market cannot meet our needs, which brings inconvenience to practical applications.

[0003] Based on this situation, we disclose a method for preparing nickel-chromium plated steel strip to solve this technical problem. Summary of the invention

[0004] The object of the present invention is to provide a method for preparing a nickel-chromium plated steel strip to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0007] (1) Taking a two-dimensional titanium carbide composite material, placing it in a nickel plating solution after surface activation, plating at 55-60° C. for 10-20 minutes, collecting the product by centrifugation, washing and drying, and then transferring it to a nickel-chromium plating solution, plating at 75-80° C. for 20-30 minutes, centrifugally washing, and vacuum drying to obtain a two-dimensional titanium carbide with a nickel-chromium plated surface; the two-dimensional titanium carbide composite material is obtained by compounding two-dimensional titanium carbide and aluminum oxide;

[0008] (2) Take a stainless steel strip, polish the surface, place it in acetone, and ultrasonically clean it for 20 to 30 minutes. Then, ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate.

[0009] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 20-30 minutes, immerse the pretreated substrate, and electroplate for 15-20 minutes at 25-30°C with a current density of 1-2A / dm 2 , take out, wash with deionized water, and vacuum dry to obtain the finished product.

[0010] In a more optimized solution, in step (1) and step (2), the contents of the components of the nickel-chromium plating solution are: nickel sulfate 25-30 g / L, lactic acid 40-50 mL / L, chromium chloride 70-80 g / L, sodium citrate 80-90 g / L, glycine 15-20 g / L, sodium hypophosphite 18-20 g / L, boric acid 35-40 g / L, and sodium acetate 16-18 g / L.

[0011] In a more optimized solution, in step (1), the contents of the components of the nickel plating solution are: nickel sulfate 25-30 g / L, lactic acid 20-30 mL / L, glycine 15-20 g / L, sodium hypophosphite 20-25 g / L, thiourea 1-2 g / L, sodium acetate 10-12 g / L, and sodium dodecyl sulfate 3-4 g / L.

[0012] In a more optimized scheme, in step (1), the preparation steps of the two-dimensional titanium carbide composite material are as follows: mix the two-dimensional titanium carbide and N,N-dimethylformamide, and ultrasonically disperse for 30 to 40 minutes to obtain a titanium carbide dispersion; add aluminum isopropoxide, stir for 6 to 8 hours, let stand for 20 to 24 hours, filter and dry, and then transfer to a vacuum sintering furnace for heat treatment to obtain a two-dimensional titanium carbide composite material.

[0013] In a more optimized solution, the mass ratio of the two-dimensional titanium carbide to aluminum isopropoxide is 1:(4-5); and the concentration of the titanium carbide dispersion is 0.5 mg / mL.

[0014] In a more optimized solution, in step (2), the amount of two-dimensional titanium carbide with nickel-chromium plated on the surface is 10-12wt% of the nickel plating solution.

[0015] The more optimized solution is to first evacuate the vacuum to 0.1 Pa during heat treatment, heat it to 800~810℃, and heat treat it for 2~3h to obtain a two-dimensional titanium carbide composite.

[0016] In a more optimized solution, in step (2), after the substrate surface is pretreated with nickel-chromium plating, nitriding is performed. The specific steps are: placing the stainless steel strip with the nickel-chromium plating on the surface in a nitriding furnace for surface nitriding, the nitriding gas is ammonia, the ammonia flow rate is 180-190 sccm, the nitriding temperature is 450-500°C, and the holding time is 5-6 hours to obtain a finished product.

[0017] In a more optimized solution, in step (1), the surface activation step of the two-dimensional titanium carbide composite material is:

[0018] A 36 wt% hydrochloric acid solution and deionized water were mixed, stannous chloride dihydrate was added, and the mixture was stirred for 20-30 min to obtain a stannous chloride solution; palladium chloride and a 18 wt% dilute hydrochloric acid solution were mixed, and the mixture was stirred for 20-30 min to obtain a palladium chloride solution; the stannous chloride solution was added, and the mixture was stirred at 55-60° C. for 20-30 min to obtain a mixed solution A;

[0019] Take sodium chloride and deionized water, stir them evenly at 45-55°C to obtain a sodium chloride solution, add the mixed solution A, stir them at 55-60°C for 3-4 hours to obtain an activation solution; place the two-dimensional titanium carbide composite in the activation solution, stir for 1-2 hours, centrifuge, wash with deionized water until neutral, wash with hydrochloric acid for 10-15 minutes, wash with deionized water, and vacuum dry to obtain activated two-dimensional titanium carbide.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0021] The invention discloses a method for preparing a nickel-chromium plated steel strip. In the scheme, a stainless steel strip is plated with nickel-chromium to form a nickel-chromium-phosphorus ternary coating. The surface coating can effectively improve the surface corrosion resistance of the stainless steel strip. After the nickel-chromium plating, the invention further performs a gas nitriding treatment to improve the surface hardness and wear resistance of the stainless steel strip. The presence of the nickel-chromium plated transition layer can promote the adsorption and decomposition of ammonia and the transfer of active nitrogen atoms during the nitriding process, thereby improving the nitriding effect on the surface of the stainless steel strip.

[0022] In the scheme, the present application cleans the surface of the stainless steel, polishes the surface, washes it with acetone to remove oil, and then washes it with anhydrous ethanol and deionized water to remove impurities on its surface; then the cleaned stainless steel strip is placed in a nickel-chromium plating solution and chemically plated on its surface. At this time, the scheme is doped with two-dimensional titanium carbide with nickel-chromium plating on the surface. The introduction of this component can, on the one hand, improve the surface wear resistance of the nickel-chromium plating layer, and on the other hand, the introduction of two-dimensional titanium carbide with nickel-chromium plating on the surface can also promote the subsequent nitriding treatment, which can further improve the surface hardness and wear resistance of the stainless steel.

[0023] The reason is that: the present application etches with hydrofluoric acid solution and titanium aluminum carbon powder to obtain two-dimensional titanium carbide nanosheets. This component has excellent hardness and mechanical properties. Introducing it into a nickel-chromium plating solution for composite plating can effectively improve the hardness and wear resistance of the nickel-chromium-phosphorus ternary coating, and the corrosion resistance of the stainless steel strip surface is also improved; at the same time, the present application performs nickel plating and nickel-chromium plating steps on its surface to ensure the dispersibility of the two-dimensional titanium carbide nanosheets in the nickel-chromium plating solution, thereby ensuring the subsequent plating effect; in addition, since the present scheme performs nitriding treatment in the subsequent process, in order to promote the nitriding effect, the present application loads alumina on the surface of the two-dimensional titanium carbide nanosheets. The presence of alumina can also promote subsequent nitriding. Therefore, based on the above research and development concept, the scheme first loads alumina on the surface of the two-dimensional titanium carbide nanosheets, and then performs surface nickel plating and nickel-chromium plating on the obtained two-dimensional titanium carbide composite material to ensure the dispersibility of the entire composite material in the system.

[0024] The present invention discloses a method for preparing a nickel-chromium plated steel strip. The process parameters of each step are reasonable and the component ratio is appropriate. The prepared steel strip has excellent corrosion resistance, and its surface wear resistance and hardness are greatly improved. The steel strip can be widely used in multiple fields and has high practicality. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In this embodiment, the contents of the components of the nickel plating solution are: 25 g / L nickel sulfate, 20 mL / L lactic acid, 15 g / L glycine, 25 g / L sodium hypophosphite, g / L thiourea, 10 g / L sodium acetate, and 3 g / L sodium dodecyl sulfonate. The contents of the components of the nickel-chromium plating solution are: 25 g / L nickel sulfate, 40 mL / L lactic acid, 75 g / L chromium chloride, 85 g / L sodium citrate, 18 g / L glycine, 20 g / L sodium hypophosphite, 35 g / L boric acid, and 18 g / L sodium acetate.

[0027] The preparation steps of two-dimensional titanium carbide are as follows: take a hydrofluoric acid solution with a concentration of 40wt%, stir it at 45°C for 5min, add titanium aluminum carbon powder, stir it at 60°C for 20h, centrifuge, wash it with deionized water until it is neutral, and vacuum dry it at 70°C to obtain two-dimensional titanium carbide; the amount of the titanium aluminum carbon powder and hydrofluoric acid solution used is 3g:60mL.

[0028] The surface activation step of the two-dimensional titanium carbide composite material is as follows: taking a 36wt% hydrochloric acid solution and mixing it with deionized water, adding stannous chloride dihydrate, stirring for 25 minutes, and obtaining a stannous chloride solution, wherein the concentration of the stannous chloride dihydrate is 0.15g / mL. Taking palladium chloride and a 18wt% dilute hydrochloric acid solution, stirring for 25 minutes, obtaining a palladium chloride solution, wherein the concentration of the palladium chloride is 5mg / mL; adding the stannous chloride solution, stirring at 60°C for 25 minutes, and obtaining a mixed solution A.

[0029] Take sodium chloride and deionized water, stir them evenly at 50°C to obtain a sodium chloride solution, the concentration of which is 200 g / L; add mixed solution A, stir at 60°C for 3 hours to obtain an activation solution; place the two-dimensional titanium carbide composite in the activation solution, stir for 1.5 hours, centrifuge, wash with deionized water until neutral, wash with hydrochloric acid for 15 minutes, wash with deionized water, and vacuum dry to obtain activated two-dimensional titanium carbide.

[0030] The mass ratio of palladium chloride to stannous chloride dihydrate is 1:40; the mass ratio of stannous chloride dihydrate to sodium chloride is 1:10, the volume ratio of the 36wt% hydrochloric acid solution to deionized water is 1:2, and the amount of the two-dimensional titanium carbide composite material and the activation solution is 2g:80mL.

[0031] In this embodiment, the stainless steel strip is a cold-rolled steel strip (BDCK) specially made for battery shells of Baosteel, and its size is 130 mm×60 mm×0.3 mm.

[0032] Embodiment 1:

[0033] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0034] (1) Mix two-dimensional titanium carbide and N,N-dimethylformamide, and ultrasonically disperse for 30 minutes to obtain a titanium carbide dispersion; the concentration of the titanium carbide dispersion is 0.5 mg / mL; add aluminum isopropoxide, stir for 6 hours, let stand for 20 hours, filter and dry, and then transfer to a vacuum sintering furnace for heat treatment. During the heat treatment, first evacuate to 0.1 Pa, heat to 800°C at a rate of 8°C / min, and heat treat for 3 hours to obtain a two-dimensional titanium carbide composite. The mass ratio of the two-dimensional titanium carbide to aluminum isopropoxide is 1:5.

[0035] Take a two-dimensional titanium carbide composite, place it in a nickel plating solution after surface activation, plate it at 55°C for 20 minutes, collect the product by centrifugation, wash and dry it, then transfer it to a nickel-chromium plating solution, plate it at 75°C for 30 minutes, centrifuge and wash it, and vacuum dry it to obtain a two-dimensional titanium carbide with nickel-chromium plated on the surface.

[0036] (2) Take a stainless steel strip, polish the surface, place it in acetone, and ultrasonically clean it for 20 minutes. Then, ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate.

[0037] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 20 minutes, immerse the pretreated substrate, and electroplate for 20 minutes at 25°C with a current density of 1A / dm 2 , washed with deionized water, and dried in vacuum to obtain a finished product. The amount of the two-dimensional titanium carbide with nickel-chromium plating on the surface is 10wt% of the nickel plating solution.

[0038] Embodiment 2:

[0039] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0040] (1) Mix two-dimensional titanium carbide and N,N-dimethylformamide, and ultrasonically disperse for 35 minutes to obtain a titanium carbide dispersion; the concentration of the titanium carbide dispersion is 0.5 mg / mL; add aluminum isopropoxide, stir for 7 hours, let stand for 22 hours, filter and dry, and then transfer to a vacuum sintering furnace for heat treatment. During the heat treatment, first evacuate to 0.1 Pa, heat to 805°C at a rate of 8°C / min, and heat treat for 2.5 hours to obtain a two-dimensional titanium carbide composite. The mass ratio of the two-dimensional titanium carbide to aluminum isopropoxide is 1:5.

[0041] Take a two-dimensional titanium carbide composite, place it in a nickel plating solution after surface activation, plate it at 60°C for 15 minutes, collect the product by centrifugation, wash and dry it, then transfer it to a nickel-chromium plating solution, plate it at 80°C for 25 minutes, wash it by centrifugation, and vacuum dry it to obtain a two-dimensional titanium carbide with nickel-chromium plated on the surface.

[0042] (2) Take a stainless steel strip, polish the surface, place it in acetone, ultrasonically clean it for 25 minutes, then ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate;

[0043] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 25 minutes, immerse the pretreated substrate, and electroplate at 30°C for 18 minutes with a current density of 1A / dm 2 , washed with deionized water, and dried in vacuum to obtain a finished product. The amount of the two-dimensional titanium carbide with nickel-chromium plating on the surface is 10wt% of the nickel plating solution.

[0044] Embodiment 3:

[0045] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0046] (1) Mix two-dimensional titanium carbide and N,N-dimethylformamide, and ultrasonically disperse for 40 minutes to obtain a titanium carbide dispersion; the concentration of the titanium carbide dispersion is 0.5 mg / mL; add aluminum isopropoxide, stir for 8 hours, let stand for 24 hours, filter and dry, and then transfer to a vacuum sintering furnace for heat treatment. During the heat treatment, first evacuate to 0.1 Pa, heat to 810°C at a rate of 8°C / min, and heat treat for 2 hours to obtain a two-dimensional titanium carbide composite. The mass ratio of the two-dimensional titanium carbide to aluminum isopropoxide is 1:5.

[0047] Take a two-dimensional titanium carbide composite, place it in a nickel plating solution after surface activation, plate it at 60°C for 20 minutes, collect the product by centrifugation, wash and dry it, then transfer it to a nickel-chromium plating solution, plate it at 80°C for 20 minutes, wash it by centrifugation, and vacuum dry it to obtain a two-dimensional titanium carbide with nickel-chromium plated on the surface.

[0048] (2) Take a stainless steel strip, polish the surface, place it in acetone, and ultrasonically clean it for 30 minutes. Then, ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate.

[0049] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 30 minutes, immerse the pretreated substrate, and electroplate for 15 minutes at 30°C with a current density of 1A / dm 2 , washed with deionized water, and dried in vacuum to obtain a finished product. The amount of the two-dimensional titanium carbide with nickel-chromium plating on the surface is 10wt% of the nickel plating solution.

[0050] Embodiment 4:

[0051] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0052] (1) Mix two-dimensional titanium carbide and N,N-dimethylformamide, and ultrasonically disperse for 35 minutes to obtain a titanium carbide dispersion; the concentration of the titanium carbide dispersion is 0.5 mg / mL; add aluminum isopropoxide, stir for 7 hours, let stand for 22 hours, filter and dry, and then transfer to a vacuum sintering furnace for heat treatment. During the heat treatment, first evacuate to 0.1 Pa, heat to 805°C at a rate of 8°C / min, and heat treat for 2.5 hours to obtain a two-dimensional titanium carbide composite. The mass ratio of the two-dimensional titanium carbide to aluminum isopropoxide is 1:5.

[0053] Take a two-dimensional titanium carbide composite, place it in a nickel plating solution after surface activation, plate it at 60°C for 15 minutes, collect the product by centrifugation, wash and dry it, then transfer it to a nickel-chromium plating solution, plate it at 80°C for 25 minutes, wash it by centrifugation, and vacuum dry it to obtain a two-dimensional titanium carbide with nickel-chromium plated on the surface.

[0054] (2) Take a stainless steel strip, polish the surface, place it in acetone, ultrasonically clean it for 25 minutes, then ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate;

[0055] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 25 minutes, immerse the pretreated substrate, and electroplate at 30°C for 18 minutes with a current density of 1A / dm 2 , taken out for washing with deionized water, and dried in vacuum; the amount of two-dimensional titanium carbide with nickel-chromium plating on the surface is 10wt% of the nickel plating solution.

[0056] (3) The stainless steel strip with nickel-chromium plating on the surface is placed in a nitriding furnace for surface nitriding. The nitriding gas is ammonia, the ammonia flow rate is 180 sccm, the nitriding temperature is 500°C, and the holding time is 5 hours to obtain a finished product.

[0057] Comparative Example 1: Example 3 was used as the control group. In Comparative Example 1, two-dimensional titanium carbide with nickel-chromium plating on the surface was not introduced, and the other steps remained unchanged.

[0058] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0059] (1) Take a stainless steel strip, polish the surface, place it in acetone, and ultrasonically clean it for 30 minutes. Then, ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate;

[0060] Take the nickel-chromium plating solution, immerse the pretreated substrate, and electroplate for 15 minutes at 30°C with a current density of 1A / dm 2 , take out, wash with deionized water, and vacuum dry to obtain the finished product.

[0061] Comparative Example 2: Example 3 was used as the control group. In Comparative Example 2, the two-dimensional titanium carbide was not subjected to surface nickel-chromium plating, and the other steps remained unchanged.

[0062] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0063] (1) Mix two-dimensional titanium carbide and N,N-dimethylformamide, and ultrasonically disperse for 40 minutes to obtain a titanium carbide dispersion; the concentration of the titanium carbide dispersion is 0.5 mg / mL; add aluminum isopropoxide, stir for 8 hours, let stand for 24 hours, filter and dry, and then transfer to a vacuum sintering furnace for heat treatment. During the heat treatment, first evacuate to 0.1 Pa, heat to 810°C at a rate of 8°C / min, and heat treat for 2 hours to obtain a two-dimensional titanium carbide composite. The mass ratio of the two-dimensional titanium carbide to aluminum isopropoxide is 1:5.

[0064] (2) Take a stainless steel strip, polish the surface, place it in acetone, and ultrasonically clean it for 30 minutes. Then, ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate.

[0065] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide composite material, ultrasonically disperse for 30 minutes, immerse the pretreated substrate, and electroplate for 15 minutes at 30°C with a current density of 1A / dm 2 The product is taken out for washing with deionized water and vacuum drying to obtain the finished product. The amount of the two-dimensional titanium carbide composite material is 10wt% of the nickel plating solution.

[0066] Comparative Example 3: Example 3 was used as the control group. In Comparative Example 3, alumina was not loaded on the two-dimensional titanium carbide, and the other steps remained unchanged.

[0067] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0068] (1) Take two-dimensional titanium carbide, place it in a nickel plating solution after surface activation, plate it at 60°C for 20 minutes, collect the product by centrifugation, wash and dry it, then transfer it to a nickel-chromium plating solution, plate it at 80°C for 20 minutes, wash it by centrifugation, and vacuum dry it to obtain a two-dimensional titanium carbide with a nickel-chromium surface plating.

[0069] (2) Take a stainless steel strip, polish the surface, place it in acetone, and ultrasonically clean it for 30 minutes. Then, ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate.

[0070] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 30 minutes, immerse the pretreated substrate, and electroplate for 15 minutes at 30°C with a current density of 1A / dm 2 , washed with deionized water, and dried in vacuum to obtain a finished product. The amount of the two-dimensional titanium carbide with nickel-chromium plating on the surface is 10wt% of the nickel plating solution.

[0071] Comparative Example 4: Example 3 was used as the control group. In Comparative Example 4, the two-dimensional titanium carbide was not nickel-plated, but was directly plated with nickel-chromium, and the other steps remained unchanged.

[0072] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0073] (1) Mix two-dimensional titanium carbide and N,N-dimethylformamide, and ultrasonically disperse for 40 minutes to obtain a titanium carbide dispersion; the concentration of the titanium carbide dispersion is 0.5 mg / mL; add aluminum isopropoxide, stir for 8 hours, let stand for 24 hours, filter and dry, and then transfer to a vacuum sintering furnace for heat treatment. During the heat treatment, first evacuate to 0.1 Pa, heat to 810°C at a rate of 8°C / min, and heat treat for 2 hours to obtain a two-dimensional titanium carbide composite. The mass ratio of the two-dimensional titanium carbide to aluminum isopropoxide is 1:5.

[0074] Take a two-dimensional titanium carbide composite material, place it in a nickel-chromium plating solution after surface activation, plate it at 80°C for 20 minutes, centrifuge and wash it, and vacuum dry it to obtain a two-dimensional titanium carbide with nickel-chromium plated on the surface.

[0075] (2) Take a stainless steel strip, polish the surface, place it in acetone, and ultrasonically clean it for 30 minutes. Then, ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate.

[0076] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 30 minutes, immerse the pretreated substrate, and electroplate for 15 minutes at 30°C with a current density of 1A / dm 2 , washed with deionized water, and dried in vacuum to obtain a finished product. The amount of the two-dimensional titanium carbide with nickel-chromium plating on the surface is 10wt% of the nickel plating solution.

[0077] Comparative Example 5: Example 4 was used as the control group. In Comparative Example 5, the two-dimensional titanium carbide was not loaded with alumina, and the other steps remained unchanged.

[0078] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0079] (1) Take two-dimensional titanium carbide, place it in a nickel plating solution after surface activation, plate it at 60°C for 15 minutes, collect the product by centrifugation, wash and dry it, then transfer it to a nickel-chromium plating solution, plate it at 80°C for 25 minutes, wash it by centrifugation, and vacuum dry it to obtain a two-dimensional titanium carbide with a nickel-chromium surface plating.

[0080] (2) Take a stainless steel strip, polish the surface, place it in acetone, ultrasonically clean it for 25 minutes, then ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate;

[0081] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 25 minutes, immerse the pretreated substrate, and electroplate at 30°C for 18 minutes with a current density of 1A / dm 2 , taken out for washing with deionized water, and dried in vacuum; the amount of two-dimensional titanium carbide with nickel-chromium plating on the surface is 10wt% of the nickel plating solution.

[0082] (3) The stainless steel strip with nickel-chromium plating on the surface is placed in a nitriding furnace for surface nitriding. The nitriding gas is ammonia, the ammonia flow rate is 180 sccm, the nitriding temperature is 500°C, and the holding time is 5 hours to obtain a finished product.

[0083] Comparative Example 6: Example 4 was used as the control group. In Comparative Example 6, the two-dimensional titanium carbide was not nickel-plated, but was directly plated with nickel-chromium, and the other steps remained unchanged.

[0084] A method for preparing a nickel-chromium plated steel strip comprises the following steps:

[0085] (1) Mix two-dimensional titanium carbide and N,N-dimethylformamide, and ultrasonically disperse for 35 minutes to obtain a titanium carbide dispersion; the concentration of the titanium carbide dispersion is 0.5 mg / mL; add aluminum isopropoxide, stir for 7 hours, let stand for 22 hours, filter and dry, and then transfer to a vacuum sintering furnace for heat treatment. During the heat treatment, first evacuate to 0.1 Pa, heat to 805°C at a rate of 8°C / min, and heat treat for 2.5 hours to obtain a two-dimensional titanium carbide composite. The mass ratio of the two-dimensional titanium carbide to aluminum isopropoxide is 1:5.

[0086] Take a two-dimensional titanium carbide composite material, place it in a nickel-chromium plating solution after surface activation, plate it at 80°C for 25 minutes, centrifuge and wash it, and vacuum dry it to obtain a two-dimensional titanium carbide with nickel-chromium plated on the surface.

[0087] (2) Take a stainless steel strip, polish the surface, place it in acetone, ultrasonically clean it for 25 minutes, then ultrasonically clean it with anhydrous ethanol and deionized water in sequence, and vacuum dry it to obtain a pretreated substrate;

[0088] Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 25 minutes, immerse the pretreated substrate, and electroplate at 30°C for 18 minutes with a current density of 1A / dm 2 , taken out for washing with deionized water, and dried in vacuum; the amount of two-dimensional titanium carbide with nickel-chromium plating on the surface is 10wt% of the nickel plating solution.

[0089] (3) The stainless steel strip with nickel-chromium plating on the surface is placed in a nitriding furnace for surface nitriding. The nitriding gas is ammonia, the ammonia flow rate is 180 sccm, the nitriding temperature is 500°C, and the holding time is 5 hours to obtain a finished product.

[0090] Detection experiment:

[0091] 1. Take the steel strip samples prepared in Examples 1-4 and Comparative Examples 1-7, and perform hardness tests on the samples using a Vickers hardness tester according to standard QB / T3822-1999. The test load is 10 g, and the microhardness is recorded.

[0092] 2. Take the steel strip samples prepared in Examples 1-4 and Comparative Examples 1-7 and conduct a neutral salt spray test. The test conditions are: temperature 35°C, 5% NaCl solution, pH 7, and continuous spraying for 24 hours. After the spray test, they are rated, where 10 is no defect area and no change in appearance; 9 is that the defect area accounts for no more than 0.1%, and the surface of the sample is slightly to moderately discolored; 8 is that the defect area accounts for 0.1% to 0.25%, and the surface of the sample is severely discolored or has slight corrosion products; 7 is that the defect area accounts for 0.25% to 0.5%, and the surface of the sample is severely glossy or has slight corrosion products.

[0093] project Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Microhardness (HV) 289 291 297 486 231 Corrosion resistance Level 9 Level 9 Level 9 Level 10 Level 7 project Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Microhardness 274 285 293 402 474 Corrosion resistance Level 8 Level 8 Level 8 Level 8 Level 9

[0094] Conclusion: This scheme discloses a method for preparing nickel-chromium-plated steel strip. The process parameters of each step are reasonable and the component ratio is appropriate. The prepared steel strip has excellent corrosion resistance, and its surface wear resistance and hardness are greatly improved. It can be widely used in multiple fields and has high practicality.

[0095] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a nickel-chromium plated steel strip, characterized in that: The following steps are involved: (1) Taking a two-dimensional titanium carbide composite material, placing it in a nickel plating solution after surface activation, plating at 55-60° C. for 10-20 minutes, collecting the product by centrifugation, washing and drying, and then transferring it to a nickel-chromium plating solution, plating at 75-80° C. for 20-30 minutes, centrifugally washing, and vacuum drying to obtain a two-dimensional titanium carbide with a nickel-chromium plated surface; the two-dimensional titanium carbide composite material is obtained by compounding two-dimensional titanium carbide and aluminum oxide; (2) taking a stainless steel strip, polishing the surface, placing it in acetone, ultrasonically cleaning it, and then ultrasonically cleaning it with anhydrous ethanol and deionized water in sequence, and vacuum drying it to obtain a pretreated substrate; Take the nickel-chromium plating solution, add the two-dimensional titanium carbide with nickel-chromium plating on the surface, ultrasonically disperse for 20-30 minutes, immerse the pretreated substrate, and electroplate for 15-20 minutes at 25-30°C with a current density of 1-2A / dm 2 , take out deionized water for washing, vacuum dry, and obtain the finished product; In step (1), the surface activation step of the two-dimensional titanium carbide composite material is: Take a hydrochloric acid solution and deionized water, mix them, add stannous chloride dihydrate, stir and mix, and obtain a stannous chloride solution; take a palladium chloride and a dilute hydrochloric acid solution, stir and mix, add the stannous chloride solution, stir at 55-60° C. for 20-30 minutes, and obtain a mixed solution A; Take sodium chloride and deionized water, stir them evenly at 45-55°C to obtain a sodium chloride solution, add the mixed solution A, stir them at 55-60°C for 3-4 hours to obtain an activation solution; place the two-dimensional titanium carbide composite material in the activation solution, stir for 1-2 hours, centrifuge, wash with deionized water until neutral, wash with hydrochloric acid, wash with deionized water, and vacuum dry; In step (1) and step (2), the contents of the components of the nickel-chromium plating solution are: 25-30 g / L nickel sulfate, 40-50 mL / L lactic acid, 70-80 g / L chromium chloride, 80-90 g / L sodium citrate, 15-20 g / L glycine, 18-20 g / L sodium hypophosphite, 35-40 g / L boric acid, and 16-18 g / L sodium acetate; In step (1), the contents of the components of the nickel plating solution are: 25-30 g / L nickel sulfate, 20-30 mL / L lactic acid, 15-20 g / L glycine, 20-25 g / L sodium hypophosphite, 1-2 g / L thiourea, 10-12 g / L sodium acetate, and 3-4 g / L sodium dodecyl sulfonate; In step (1), the preparation steps of the two-dimensional titanium carbide composite material are as follows: mixing two-dimensional titanium carbide and N,N-dimethylformamide, and ultrasonically dispersing to obtain a titanium carbide dispersion; adding aluminum isopropoxide, stirring for 6 to 8 hours, standing for 20 to 24 hours, filtering and drying, and then transferring to a vacuum sintering furnace for heat treatment to obtain a two-dimensional titanium carbide composite material.

2. The method for preparing a nickel-chromium plated steel strip according to claim 1, characterized in that: The mass ratio of the two-dimensional titanium carbide to aluminum isopropoxide is 1:(4-5); the concentration of the titanium carbide dispersion is 0.5 mg / mL.

3. The method for preparing a nickel-chromium plated steel strip according to claim 1, characterized in that: During the heat treatment, the vacuum is first evacuated to 0.1 Pa, the temperature is raised to 800-810°C, and the heat treatment is performed for 2-3 hours to obtain a two-dimensional titanium carbide composite material.

4. The method for preparing a nickel-chromium plated steel strip according to claim 1, characterized in that: In step (2), after the surface of the substrate is pretreated with nickel-chromium plating, nitriding is performed. The specific steps are: placing the stainless steel strip with the nickel-chromium plating on the surface in a nitriding furnace for surface nitriding, the nitriding gas is ammonia, the ammonia flow rate is 180-190sccm, the nitriding temperature is 450-500°C, and the holding time is 5-6h to obtain a finished product.