Electroplating process method for wind power equipment coating

Abstract

According to the electroplating process method for the wind power equipment coating, compared with a traditional pure zinc coating, the corrosion resistance and the oxidation resistance are greatly improved. Besides, aiming at the problem that an existing composite complexing agent is difficult to improve the corrosion resistance of a plating layer, the invention provides a quaternary composite complexing agent capable of effectively improving the corrosion resistance of the plating layer, and the plating layer has more excellent corrosion resistance through a synergistic complexing effect.

Description

Technical Field

[0001] This invention relates to the field of metal surface treatment, specifically to an electroplating process for coatings used in wind power equipment. Background Technology

[0002] Wind power equipment refers to all mechanical, electrical, and electronic equipment used to convert wind energy into electrical energy. It mainly consists of blades, hubs, main shafts, gearboxes, couplings, and towers. Because wind power equipment is mostly used in harsh onshore and offshore environments, it has high requirements for corrosion resistance, thus necessitating a certain degree of surface treatment. Currently, electroplating zinc is a widely used electroplating process for wind power equipment, offering advantages such as low cost, mature technology, and good conductivity. Nowadays, electroplated zinc-nickel alloys are increasingly being applied to wind power equipment. Compared to traditional pure zinc plating, zinc-nickel alloy plating not only has better corrosion resistance but also stronger oxidation resistance, enabling wind power equipment to better adapt to extreme environments such as the ocean. Complexing agents play a crucial role in electroplated zinc-nickel alloys, forming stable complexes with metal ions to prevent precipitation in the plating solution. Different complexing agents have a significant impact on the corrosion resistance of the coating, and multiple complexing agents are often used in combination to obtain high-performance coatings. Existing composite complexing agents suffer from defects such as poor plating solution stability and low coating uniformity, which seriously affect the service life of wind power equipment. Therefore, the ability to develop a composite complexing agent that can significantly improve the corrosion resistance of zinc-nickel alloy coatings is a key factor in determining whether this process can be applied to wind power equipment. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a technical solution: an electroplating process for coatings on wind power equipment. The zinc-nickel alloy plating solution formula is as follows: sodium hydroxide 100g / L, zinc oxide 10g / L, nickel sulfate hexahydrate 12g / L, sodium citrate: potassium sodium tartrate: sodium gluconate: tetraethylenepentamine = 7.3:1.0:1.7:3.0, total complexing agent 84g / L, brightener 3ml / L; the process is as follows: temperature 23-27℃, cathode current density 3-5A / cm². 2 The pH value is 12.5, and the electroplating time is 10 minutes. The electroplating solution preparation process includes: pouring a calculated amount of sodium hydroxide into a small amount of water and stirring thoroughly until dissolved; pouring a calculated amount of zinc oxide into the sodium hydroxide solution obtained in step a and stirring thoroughly until dissolved; pouring a calculated amount of nickel sulfate into a small amount of water and stirring thoroughly until dissolved; pouring a calculated amount of sodium citrate into the nickel sulfate solution obtained in step c and stirring thoroughly until dissolved; and pouring a calculated amount of potassium sodium tartrate into the above solution d and stirring thoroughly until dissolved. Add the calculated amount of sodium gluconate to solution e above and stir thoroughly until dissolved; add the calculated amount of tetraethylenepentamine to solution f above and stir thoroughly until dissolved; mix the solutions from steps b and f and stir thoroughly until dissolved; add the calculated amount of water to make up to the final volume. This invention applies the electroplating zinc-nickel alloy process to the manufacturing of wind power equipment. Compared with traditional pure zinc plating, the corrosion resistance and oxidation resistance are significantly improved. Furthermore, addressing the problem that existing composite complexing agents are insufficient to improve the corrosion resistance of the coating, this invention proposes a quaternary composite complexing agent that can effectively enhance the corrosion resistance of the coating. Through synergistic complexing action, the coating exhibits superior corrosion resistance.

[0004] Compared with existing technologies, this invention has the following advantages: The coating with synergistic complexation of tricarboxylic acid and tetraethylenepentamine, as studied in this invention, shows, through SEM electron microscopy, that the coating porosity is reduced, the distribution is more uniform, and the density is enhanced, thus exhibiting better corrosion resistance. Furthermore, electrochemical impedance spectroscopy and Tafel polarization curves further verify the enhanced corrosion resistance of the coating.

[0005] Existing monocarboxylic acid complexing agents are prone to drawbacks such as sensitivity to the working window, weak complexing ability, and difficulty in co-deposition. Monoamine complexing agents regulate coordination balance by providing coordinating atoms, but too few or too many coordinating atoms can still disrupt the co-deposition rate, resulting in coatings that cannot achieve good corrosion resistance.

[0006] The invention patent for a zinc-nickel alloy electroplating solution and its electroplating process (CN113502514A) uses amine complexing agents and sodium gluconate as complexing agents. The quaternary composite complexing agent formed by the triethylenetetramine complexing agent and tetraethylenepentamine used in this invention exhibits superior corrosion resistance compared to the aforementioned complexing agents. The invention patent for an alkaline cyanide-free zinc-nickel alloy electroplating complexing agent and its preparation method (CN20210900A) proposes a complexing agent using triethylenetetramine, citric acid, and a modified complexing agent. Compared to the complexing agent formed by the compounding of tetraethylenepentamine and triethylenetetramine in this invention, the coating of this invention has lower porosity and better corrosion resistance.

[0007] This invention adds sodium citrate, potassium sodium tartrate, and sodium gluconate to the complexing agent. The ternary complexing agent consists of a central ion and two ligands, which can form a more stable complex with metal ions, improve the corrosion resistance of the coating, and at the same time prevent the hydrolysis and precipitation of metal ions, thus extending the service life of the plating solution.

[0008] Furthermore, this invention incorporates tetraethylenepentamine into the complexing agent. Tetraethylenepentamine forms an N / O heterofunctional synergistic complexing system with the tricarboxylic acid. The tricarboxylic acid complexing agent provides oxygen coordination, and TEPA provides nitrogen coordination, forming a multilayer complex. Zn 2+ with Ni 2+The reduction potential difference decreases, improving coating properties. In the synergistic complexation process, TEPA can reduce Ni... 2+ A negative shift in reduction potential leads to a more balanced Zn / Ni co-deposition, resulting in improved coating density and corrosion resistance. Therefore, TEPA concentration is crucial for regulating the performance of the synergistic complexation system. Consequently, an electroplating process for wind power equipment overcomes the shortcomings of existing complexing agents, significantly enhancing the corrosion resistance of the coating. Detailed Implementation

[0009] This invention provides the following technical solutions: The embodiments of this invention are illustrated below through specific examples. Those skilled in the art can easily understand other advantages and effects of this invention from the content disclosed in this specification. This invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of this invention.

[0010] This invention provides a technical solution: an electroplating process for coatings on wind power equipment, characterized in that the zinc-nickel alloy plating solution formula is: sodium hydroxide 100g / L, zinc oxide 10g / L, nickel sulfate hexahydrate 12g / L, sodium citrate: potassium sodium tartrate: sodium gluconate: tetraethylenepentamine = 7.3:1.0:1.7:3.0, total complexing agent 84g / L, brightener 3ml / L; the process is as follows: temperature 23-27℃, cathode current density 3-5A / cm². 2 The pH value is 12.5, and the electroplating time is 10 minutes. The electroplating process includes: pouring a calculated amount of sodium hydroxide into a small amount of water and stirring thoroughly until dissolved; pouring a calculated amount of zinc oxide into the sodium hydroxide solution obtained in step a and stirring thoroughly until dissolved; pouring a calculated amount of nickel sulfate into a small amount of water and stirring thoroughly until dissolved; pouring a calculated amount of sodium citrate into the nickel sulfate solution obtained in step c and stirring thoroughly until dissolved; pouring a calculated amount of potassium sodium tartrate into the above solution d and stirring thoroughly until dissolved; pouring a calculated amount of sodium gluconate into the above solution e and stirring thoroughly until dissolved; pouring a calculated amount of tetraethylenepentamine into the above solution f and stirring thoroughly until dissolved; mixing the solutions from steps b and f and stirring thoroughly until dissolved; and adding a calculated amount of water to make up to the final volume.

[0011] The specific implementation steps of this embodiment are as follows: Example

[0012] Sand the sample flat with sandpaper; rinse the sample with deionized water; add 25g of sodium hydroxide and 2.5g of zinc oxide to beaker A, then add 100ml of deionized water and mix to dissolve; add 3g of nickel sulfate hexahydrate to beaker B, then add 50ml of deionized water and dissolve thoroughly; add 11.7g of sodium citrate, 1.61g of potassium sodium tartrate, and 2.83g of sodium gluconate to beaker C, then add 50ml of deionized water and dissolve, then mix. Slowly add the solution from beaker C to beaker B, stirring thoroughly until combined, then add 5ml of tetraethylenepentamine and stir until the solution is clear; slowly pour the solution from beaker B into beaker A, stirring until clear, then add 3ml of brightener; bring the volume of the mixed solution to 250ml and stir until well combined; use a low-carbon steel plate as the cathode plate, and perform pretreatment according to the steps of degreasing → water washing → pickling → water washing → pickling → water washing → activation; electroplating time 10 minutes, using 4.5A / cm 2 plating Comparative Example 1: Sand the sample flat with sandpaper; rinse the sample with deionized water; add 25g of sodium hydroxide and 2.5g of zinc oxide to beaker A, add 100ml of deionized water and mix to dissolve; add 3g of nickel sulfate hexahydrate to beaker B, add 50ml of deionized water and dissolve completely; add 11.7g of sodium citrate, 1.61g of potassium sodium tartrate, and 2.83g of sodium gluconate to beaker C, add 50ml of deionized water and dissolve, mix, slowly add the solution from beaker C to beaker B, stir thoroughly until mixed, then add 3ml of tetraethylenepentamine and stir until the solution is clear; Slowly pour the solution from beaker B into beaker A after mixing, stir until clear, and then add 3 ml of brightening agent; The mixed solution was brought to a final volume of 250 ml and stirred until homogeneous. A low-carbon steel plate was used as the cathode plate, and pretreatment was performed following the steps of degreasing → water rinsing → pickling → water rinsing → pickling → water rinsing → activation. Electroplating time was 10 minutes, using 4.5 A / cm². 2 plating Comparative Example 2: Sand the sample flat with sandpaper; rinse the sample with deionized water; add 25g of sodium hydroxide and 2.5g of zinc oxide to beaker A, dissolve them separately in 100ml of deionized water; add 3g of nickel sulfate hexahydrate to beaker B, dissolve it completely in 50ml of deionized water; add 11.7g of sodium citrate, 1.61g of potassium sodium tartrate, and 2.83g of sodium gluconate to beaker C, dissolve them separately in 50ml of deionized water, mix them, and slowly add the solution from beaker C to beaker B, stirring thoroughly until mixed. Then add 4ml of tetraethylenepentamine and stir until the solution is clear; slowly pour the mixed solution from beaker B into beaker A, stir until clear, and then add 3ml of brightener; bring the volume of the mixed solution to 250ml and stir until well mixed; use a low-carbon steel plate as the cathode plate, and perform pretreatment according to the steps of degreasing → water washing → pickling → water washing → pickling → water washing → activation; electroplating time 10 minutes, using 4.5A / cm 2 plating Example 1, compared to Comparative Examples 1 and 2, modifies the tetraethylenepentamine content in the plating bath to enhance the synergistic complexing effect of tetraethylenepentamine in the quaternary complexing agent. The comparison is primarily based on two parameters: nickel content and electrolytic thickness measurement.

[0013] Result comparison: Based on experience, the closer the nickel content of the coating is to 14%, the better its corrosion resistance and hardness. The results show that the nickel content of the coating in Example 1 is closest to 14%, therefore, Example 1 has better corrosion resistance. In the electrolytic thickness measurement experiment, the study shows that within a certain range, increasing the coating thickness can improve its corrosion resistance, which is also far superior to Comparative Example 1 and Comparative Example 2.

[0014] Therefore, this invention is applicable to electroplating processes that require high corrosion resistance for wind power equipment.

Claims

1. A process for electroplating a coating for a wind power device, characterized in that, The zinc-nickel alloy plating solution formula is: sodium hydroxide 100 g / L, zinc oxide 10 g / L, nickel sulfate hexahydrate 12 g / L, sodium citrate, potassium sodium tartrate, sodium gluconate, tetraethylene pentamine = 7.3:1.0:1.7:3.0, the total amount of complexing agent is 84 g / L, brightener 3 ml / L; its process is as follows: temperature 23-27℃, cathode current density 3-5 A / cm 2 , pH value is 12.5, plating time 10 minutes; the preparation process of the plating solution is as follows: the calculated amount of sodium hydroxide is poured into a small amount of water, and stirred until dissolved; the calculated amount of zinc oxide is poured into the sodium hydroxide solution obtained in step a, and stirred until dissolved; the calculated amount of nickel sulfate is poured into a small amount of water, and stirred until dissolved; the calculated amount of sodium citrate is poured into the nickel sulfate solution obtained in step c, and stirred until dissolved; the calculated amount of potassium sodium tartrate is poured into the above-mentioned d solution, and stirred until dissolved; the calculated amount of sodium gluconate is poured into the above-mentioned e solution, and stirred until dissolved; the calculated amount of tetraethylene pentamine is poured into the above-mentioned f solution, and stirred until dissolved; mix step b and step f solution, and stir until dissolved; add the calculated amount of water to constant volume.