A method for screening the best conditions of electroplating nickel-phosphorus-graphene

Abstract

This invention discloses a method for screening electroplating conditions for nickel-phosphorus-graphene. The method provides formulas for calculating the difference in coating thickness; formulas for linearly fitting the coating thickness to temperature at different temperatures; formulas for linearly fitting the coating thickness to current density at different current densities; and formulas for linearly fitting the coating thickness to graphene concentration at different graphene concentrations. Therefore, given values ​​for graphene concentration, current density, and temperature, these are calculated using the corresponding formulas. Based on the criterion that the sum of the variance of the results and the difference in coating thickness is as close to zero as possible, the optimal conditions for preparing nickel-phosphorus-graphene coatings can be screened. Therefore, this invention has the technical effect of screening the optimal conditions required for electroplating to improve electroplating uniformity.

Description

Technical Field

[0001] This invention relates to a method for screening the optimal electroplating conditions for nickel-phosphorus-graphene. Background Technology

[0002] Research on nickel-phosphorus alloy coatings has been a hot topic in academia in recent years. One direction involves observing changes in the coating structure and properties by adding other metals or non-metals to the plating bath, thereby expanding its application range. Graphene is hailed as a revolutionary material of the future, and recent research has revealed its excellent mechanical properties, self-lubricating properties, thermal conductivity, non-toxicity, lightweight, and high strength, making its application in alloy coatings even more promising.

[0003] In existing technologies, nickel-phosphorus-graphene coatings are generally produced using two methods: electroplating and chemical plating. Chemical plating produces coatings with uniform thickness, is easy to control, and has a smooth and flat surface. It generally does not require post-plating processing and is suitable for repairing workpieces with out-of-tolerance requirements and for selective plating. For ordinary parts, electroplating is often used to save costs. In electroplating experiments, temperature, current density, and the concentration of each component in the plating solution all affect the uniformity of the final coating. Therefore, selecting electroplating conditions suitable for the electroplating requirements can yield a more uniform electroplated coating. However, in existing technologies, electroplating experiments generally use fixed temperature, concentration, and voltage, randomly obtaining parts with good or poor coating uniformity. The poorly performing parts are then polished, increasing the workload for workers. Compared to the electroplating process with the selected optimal electroplating conditions, this method is time-consuming, labor-intensive, and produces poor electroplating results. Summary of the Invention

[0004] To at least address the technical problems of poor electroplating effect and uneven coating mentioned in the background art, the present invention provides a method for screening the optimal electroplating conditions for nickel-phosphorus-graphene. This method has the technical effect of screening out the optimal conditions required for electroplating to improve the uniformity of electroplating.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a first aspect, the present invention provides a method for screening electroplating conditions for nickel-phosphorus-graphene, comprising:

[0007] S1, preparing an electroplating solution comprising 250 g / L nickel salt, 15 g / L additional salt, 30 g / L complexing agent, 20 g / L phosphate, graphene, and water;

[0008] S2, the formula for calculating the difference in coating thickness includes:

[0009] H = H max -H min (1)

[0010] Where H represents the difference in coating thickness, H max The maximum value, H, characterizes the coating thickness. min The minimum value characterizing the coating thickness;

[0011] By fixing the graphene concentration and current density, and changing the temperature, Ha was obtained at different temperatures. T The value is linearly fitted to the corresponding temperature, resulting in the following formula:

[0012] H T =0.0001T 2 -0.0026T+0.184 (2)

[0013] By fixing the graphene concentration and temperature, and changing the current density, Ha was obtained at different current densities. A The value is linearly fitted to the corresponding current density to obtain the following formula:

[0014] H A =0.0098e 0.0231A (3)

[0015] By fixing the current density and temperature values ​​and changing the graphene concentration, Ha was obtained at different graphene concentrations. C The value was linearly fitted to the corresponding graphene concentration, yielding the following formula:

[0016] H C = -0.01C + 0.8 (4)

[0017] S3, given the values ​​of temperature, current density, and graphene concentration, calculate H using the corresponding formulas. T H A and H C The variance of the three values ​​is calculated to obtain the variance value S. 2 Summing the above three values ​​yields the sum of the differences in coating thickness, and S is selected. 2 The condition for preparing nickel-phosphorus-graphene coatings is when the sum of the values ​​of the difference between the coating thickness and the α value is closer to 0.

[0018] According to one embodiment of the present invention, the nickel salt comprises nickel sulfate.

[0019] According to one embodiment of the present invention, the additional salt comprises nickel chloride.

[0020] According to one embodiment of the present invention, the complexing agent comprises boric acid.

[0021] According to one embodiment of the present invention, the phosphate comprises sodium hypophosphite.

[0022] In a second aspect, the present invention also provides a computer device, including a processor and a memory, wherein the memory stores computer program instructions for execution on the processor, and the processor, when executing the computer program instructions, implements a method for screening electroplating conditions for nickel-phosphorus-graphene as described in any of the preceding claims.

[0023] Thirdly, the present invention also provides a computer storage medium storing computer instructions, which, when executed by a processor, implement a method for screening electroplating conditions for nickel-phosphorus-graphene according to any one of the preceding claims.

[0024] The technical solution of this invention provides a method for calculating the optimal experimental temperature, current density, and graphene concentration for nickel-phosphorus-graphene electroplating experiments. Compared with nickel-phosphorus-graphene electroplating experiments with fixed single values ​​of experimental temperature, current density, and graphene concentration, this method solves the technical problems of time-consuming and labor-intensive electroplating and poor electroplating effect. It has the technical effect of being able to screen out the optimal conditions required for electroplating to improve the uniformity of electroplating. Attached Figure Description

[0025] Figure 1 This is a flowchart of a method for screening optimal electroplating conditions for nickel-phosphorus-graphene according to the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of a computer device according to an embodiment of the present invention. Detailed Implementation

[0027] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0028] Please refer to Figure 1 This application provides a method for screening electroplating conditions for nickel-phosphorus-graphene, comprising:

[0029] In step S1, an electroplating solution is prepared, comprising 250 g / L nickel salt, 15 g / L additional salt, 30 g / L complexing agent, 20 g / L phosphate, graphene, and water.

[0030] The specific steps are as follows: Weigh 125g of nickel salt using a balance and pour it into a beaker. Add 400ml of water to dissolve it and stir with a glass rod. Then, weigh out 7.5g, 7.5g, 15g, 3g, and 10g of additional salt, NaCl, complexing agent, and phosphate in sequence and pour them into the beaker. Add water to approximately 500ml, then use a dropper to bring the volume to 500ml. Add a magnetic stirrer and adjust the stirring speed to 300r / m-1 to accelerate dissolution. The nickel salt provides Ni ions needed for electroplating, and the phosphate provides P ions needed for electroplating.

[0031] Pour the above electroplating solution into the electroplating tank, insert the anode and cathode electrodes into the tank, and connect them via a DC power supply. The anode is a nickel plate, and the cathode is a steel plate. The nickel and steel plates must undergo the following treatment before the electroplating experiment can be performed:

[0032] The nickel plate is polished with 240-grit sandpaper. After polishing, it is washed with tap water and then cleaned with dish soap to remove oil. It is then placed in an ultrasonic vibration cleaner (with deionized water added) until no impurities float on the surface of the nickel plate. During the process, the nickel plate is turned over with tweezers every 20-30 seconds. The nickel plate is then removed with tweezers, the surface moisture is dried with gauze, and it is clamped with clips and placed into the electroplating solution.

[0033] The steel plate is made of No. 45 steel, with dimensions of 30×30 mm. First, the steel plate is wet-ground: wet the sandpaper and grind the steel plate along a straight line. Once there is noticeable no resistance, move to a different position and continue grinding in the same direction. Use 240 grit, 600 grit, and 1000 grit sandpaper successively. After each sandpaper application, the steel plate must be thoroughly rinsed. After grinding, clean with detergent to remove oil stains. Sandblasting is then performed to make the steel plate surface smoother and more uniform. After sandblasting, the steel plate is ultrasonically cleaned, then dipped in alcohol, and then rinsed again with deionized water. Acid-alkali washing: prepare a 3% NaOH solution and H2SO4 solution in advance. First, perform an alkaline wash on the steel plate for about 30 seconds, then remove the steel plate with tweezers and rinse with deionized water, followed by ultrasonic cleaning, and then rinsing with deionized water again. Finally, perform an acid wash for 30 seconds. After observing no more bubbles, the steel plate can be rinsed, following the same rinsing process as the alkaline wash. Use small clips to hold the steel plate and place it in the electroplating solution, keeping the steel plate parallel to the nickel plate.

[0034] In step S2, the formula for calculating the difference in coating thickness includes:

[0035] H = H max -H min (1)

[0036] Where H represents the difference in coating thickness, H max The maximum value, H, characterizes the coating thickness. min The minimum value characterizing the coating thickness;

[0037] In this step, a coating thickness gauge is used to obtain the coating thickness values ​​at different locations on the workpiece. The maximum and minimum values ​​of the coating thickness are subtracted to obtain the H value, which is the difference in coating thickness.

[0038] By fixing the graphene concentration and current density, and changing the temperature, Ha was obtained at different temperatures. T The value is linearly fitted to the corresponding temperature, resulting in the following formula:

[0039] H T =0.0001T 2 -0.0026T+0.184 (2)

[0040] The specific calculation method of formula (2) is as follows: by using the method of controlling variables, the values ​​of graphene concentration and current density are fixed, and the electroplating temperature during the electroplating process is changed by using a water bath and a temperature-controlled magnetic stirrer. The temperature is increased or decreased in a gradient around 70 degrees Celsius. Referring to formula (1), the difference in the coating thickness of the plated part under different temperature conditions is recorded. The difference is linearly fitted with the temperature to obtain the correlation formula (2).

[0041] By fixing the graphene concentration and temperature, and changing the current density, Ha was obtained at different current densities. A The value is linearly fitted to the corresponding current density to obtain the following formula:

[0042] H A =0.0098e 0.0231A (3)

[0043] The specific calculation method of formula (3) is as follows: by using the method of controlling variables, the values ​​of graphene concentration and temperature are fixed, and the current density in the electroplating process is changed. The current density is increased or decreased in a gradient around 50mA·cm. Referring to formula (1), the difference in the thickness of the coating of the workpiece under different current density conditions is recorded. The difference is linearly fitted with the current density to obtain its correlation formula (3).

[0044] By fixing the current density and temperature values ​​and changing the graphene concentration, Ha was obtained at different graphene concentrations. C The value was linearly fitted to the corresponding graphene concentration, yielding the following formula:

[0045] H C = -0.01C + 0.8 (4)

[0046] The specific calculation method of formula (4) is to use the method of controlling variables, fix the values ​​of current density and temperature, change the graphene concentration in the electroplating process, refer to formula (1), record the difference in coating thickness of the plated part under different graphene concentration conditions, and perform linear fitting between the difference and the graphene concentration to obtain its correlation formula (4).

[0047] In step S3, given the values ​​of temperature, current density, and graphene concentration, they are calculated using the corresponding formulas to obtain H. T H A and H C The variance of the three values ​​is calculated to obtain the variance value S. 2 Summing the above three values ​​yields the sum of the differences in coating thickness, and S is selected. 2 The condition for preparing nickel-phosphorus-graphene coatings is when the sum of the values ​​of the difference between the coating thickness and the α value is closer to 0.

[0048] H T H A and H C The numerical values ​​are calculated by substituting the values ​​of temperature, current density, and graphene concentration into formulas (2), (3), and (4), respectively. For example, H T The calculation method is to substitute the temperature value into formula (2) to obtain H at that temperature. T Under this condition, H T H A and H CThe values ​​are summed. Theoretically, the more uniform the coating thickness of the workpiece, the better the electroplating effect. That is, the closer the difference H between the maximum and minimum values ​​of the coating thickness is to zero, the closer the sum of the three values ​​should be to zero, indicating that the electroplating conditions are good. Simultaneously, variance is calculated for the three values ​​to determine their dispersion. Theoretically, the smaller the dispersion of the three values, the closer the variance is to zero, indicating that the three values ​​are most similar. The existence of variance avoids the extreme influence of a single factor on the electroplating thickness, ensuring that the influence of the three factors on the coating thickness is as uniform as possible. For example, under certain conditions of temperature, current density, and graphene concentration, the difference in coating thickness caused by temperature is 0.1 μm, and the difference in coating thickness caused by current density is 1.9 μm. Under another certain condition of temperature, current density, and graphene concentration, the difference in coating thickness caused by temperature is 1 μm, and the difference in coating thickness caused by current density is also 1 μm. In both cases, the difference in coating thickness is 2 μm. However, it is clear that the difference in coating thickness caused by the current density is too large in the first case, resulting in an uneven coating thickness on the workpiece. Therefore, the variance calculation method can eliminate this situation and select the best experimental conditions.

[0049] The electroplating process and principle generally include:

[0050] Dispersion stage: After graphene nanoparticles are added to the plating solution, under the action of external stirring and their own Brownian motion, the graphene nanoparticles gradually disperse from the aggregated state.

[0051] Adsorption Stage: There are two hypotheses for this stage. The first hypothesis suggests that whether graphene nanoparticles can be adsorbed onto the cathode workpiece surface is mainly influenced by van der Waals forces. That is, under the influence of van der Waals forces, the graphene nanoparticles gradually move to the cathode surface and are adsorbed onto the newly formed coating surface. The second hypothesis is the electrophoretic theory, which states that graphene nanoparticles selectively adsorb nickel and phosphorus ions in the metal plating solution, forming positively charged particles. After energizing, the positively charged nanoparticles migrate towards the negatively charged cathode workpiece surface under the influence of the electric field, thus being adsorbed onto the cathode surface.

[0052] Coating stage: As the redox reaction proceeds in the plating bath, graphene nanoparticles are continuously adsorbed onto the surface of the cathode workpiece and co-deposited with nickel and phosphorus ions in the plating bath, gradually embedding themselves into the coating. When the nanoparticle density is less than or equal to the coating thickness, the particles are completely coated by the coating, thus forming a nickel-phosphorus-graphene composite coating.

[0053] In summary, the technical solution of this application obtains the relationship between a single variable and the difference in coating thickness of the plated part by controlling a single variable. Therefore, given the values ​​of multiple fixed variables, it is possible to analyze them separately to obtain the difference in coating thickness under each variable. The differences are then summed and variances are calculated. After screening, the optimal experimental conditions are obtained. Therefore, the method provided by this invention has the technical effect of screening out the optimal conditions required for electroplating to improve the uniformity of electroplating.

[0054] In one embodiment, the nickel salt comprises nickel sulfate. Nickel salts generally include sulfate type, chloride type, aminosulfonate type, etc., with sulfate type being Watt's solution, which has the advantages of low cost and easy availability.

[0055] In one embodiment, the aforementioned additional salt includes nickel chloride. Nickel chloride provides conductivity as an additional salt. Furthermore, the additional salt may also include sodium chloride. Both nickel chloride and sodium chloride are anodic activators, easy to manufacture and inexpensive, capable of preventing anodic passivation and improving the conductivity of the electroplating solution.

[0056] In one embodiment, the complexing agent includes boric acid. The complexing agent may generally be a variety of substances such as sodium citrate, sodium tartrate, or boric acid. However, boric acid not only adjusts the pH of the plating bath to maintain the acidic environment required for electroplating, but also helps improve the mechanical properties of the coating, thus enhancing the electroplating effect.

[0057] In one embodiment, the phosphate comprises sodium hypophosphite. The phosphate may also include sodium phosphite or other phosphates that provide phosphorus, all of which offer the advantages of low cost and easy availability.

[0058] According to a second aspect of the invention, the invention also provides a computer device, such as... Figure 2 As shown, the device includes a processor, a memory, a communication interface, and a communication bus. The processor, memory, and communication interface communicate with each other via the communication bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer program instructions. The internal memory provides an environment for the operation of the operating system and computer program instructions in the non-volatile storage medium. The communication interface of the device is used for wired or wireless communication with external terminals. Wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. The memory stores computer program instructions that cause the processor to execute the above-described invention. Figure 1 This paper presents a method for screening the optimal electroplating conditions for nickel-phosphorus-graphene.

[0059] According to a third aspect of the present invention, a computer-readable storage medium is also provided. Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by instructing related hardware through computer program instructions. These computer program instructions can be stored in a non-volatile computer-readable storage medium, and when executed, they can implement the above-described present invention. Figure 1 This invention illustrates a method for selecting optimal electroplating conditions for nickel-phosphorus-graphene. Any references to memory, storage, databases, or other media used in the embodiments provided herein may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0060] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0061] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for screening electroplating conditions for nickel-phosphorus-graphene, characterized in that, include: S1, preparing an electroplating solution comprising 250 g / L nickel salt, 15 g / L additional salt, 30 g / L complexing agent, 20 g / L phosphate, graphene, and water; S2, the formula for calculating the difference in coating thickness. include: H=H max -H min (1) Where H represents the difference in coating thickness, H max The maximum value, H, characterizes the coating thickness. min The minimum value characterizing the coating thickness; By fixing the graphene concentration and current density, and changing the electroplating bath temperature, Ha was obtained at different temperatures. T The value is linearly fitted to the corresponding temperature, resulting in the following formula: H T =0.0001T 2 -0.0026T+0.184(2) By fixing the graphene concentration and temperature, and varying the current density of the electroplating solution during the electroplating process, Ha was obtained at different current densities. A The value is linearly fitted to the corresponding current density to obtain the following formula: H A =0.0098e 0.0231A (3) By fixing the current density and temperature of the electroplating solution during the electroplating process, and varying the graphene concentration, Ha was obtained at different graphene concentrations. C The value was linearly fitted to the corresponding graphene concentration, yielding the following formula: H C =-0.01C+0.8(4) S3, given the values ​​of electroplating bath temperature, current density, and graphene concentration, calculate H using the corresponding formulas. T H A and H C The variance of the three values ​​is calculated to obtain the variance value S. 2 Summing the above three values ​​yields the sum of the differences in coating thickness, and S is selected. 2 The condition for preparing nickel-phosphorus-graphene coatings is when the sum of the values ​​of the difference between the coating thickness and the α value is closer to 0.

2. The method for screening electroplating conditions for nickel-phosphorus-graphene according to claim 1, characterized in that: The nickel salt includes nickel sulfate.

3. The method for screening electroplating conditions for nickel-phosphorus-graphene according to claim 1, characterized in that: The additional salt includes nickel chloride.

4. The method for screening electroplating conditions for nickel-phosphorus-graphene according to claim 1, characterized in that: The complexing agent includes boric acid.

5. The method for screening electroplating conditions for nickel-phosphorus-graphene according to claim 1, characterized in that: The phosphate includes sodium hypophosphite.

6. A computer device, characterized in that, The device includes a processor and a memory, the memory storing computer program instructions for execution on the processor, wherein the processor, when executing the computer program instructions, implements a method for screening electroplating conditions for nickel-phosphorus-graphene as described in any one of claims 1-5.

7. A computer storage medium, characterized in that, It stores computer instructions, which, when executed by a processor, implement a method for screening electroplating conditions for nickel-phosphorus-graphene according to any one of claims 1-5.

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