Continuous high-phosphorus chemical nickel plating method

Abstract

The invention provides a continuous high-phosphorus chemical nickel plating method, which comprises the following steps: preparing a chemical plating solution containing nickel salt, a complexing agent and an additive, adding a first reducing agent and a second reducing agent into the plating solution according to a mass ratio of (3-5): (1-2), the second reducing agent is one or more of lithium aluminum hydride, sodium borohydride, propionic acid or succinic acid; and the PH value of the plating solution needs to be adjusted to 4.5-5.5, the temperature of the plating solution is controlled to be 80-90 DEG C, and then continuous plating operation is conducted. The first reducing agent can stably release active phosphorus atoms at a low temperature, a rich phosphorus source is provided for the plating layer, and it is guaranteed that the plating layer reaches the high phosphorus content; the second reducing agent can effectively promote the reduction deposition process of nickel ions, and the deposition rate is increased. The two reducing agent components cooperate with each other, so that the plating solution keeps high stability, fluctuation of the plating solution components is effectively inhibited, and the consistency and stability of the plating layer quality are obviously improved.

Description

Technical Field

[0001] The present application belongs to the technical field of chemical nickel plating, and more specifically, to a continuous high-phosphorus chemical nickel plating method. Background Art

[0002] ‌Continuous high-phosphorus chemical nickel plating process is a process that deposits a high-phosphorus chemical nickel layer on the surface of the substrate, which can make the substrate have excellent corrosion resistance, wear resistance and high hardness. This process is suitable for a variety of substrates, such as aluminum alloy, stainless steel, alloy carbon steel, copper alloy, etc., and is widely used in industries such as electronics and petroleum, as well as fields with high requirements for corrosion resistance.

[0003] In the traditional continuous high-phosphorus chemical nickel plating process, sodium hypophosphite is used as the main reducing agent. During plating, the sodium hypophosphite in the plating solution uses its own reducing property to promote the reduction and deposition of nickel ions on the surface of the workpiece, while releasing phosphorus atoms to form a high-phosphorus chemical nickel coating. Although this method can achieve chemical nickel plating, the stability of the plating solution is poor. With the extension of plating time, the continuous consumption of sodium hypophosphite will cause significant changes in key parameters such as the pH and redox potential of the plating solution, resulting in unstable reactivity of the components in the plating solution. Moreover, the reaction process of sodium hypophosphite is difficult to accurately control, which makes the phosphorus content of the coating fluctuate in a large range, making it difficult to meet the needs of high-end products with strict requirements on the phosphorus content of the coating. In terms of coating performance, the coating obtained in this way has limited improvement effects on hardness and corrosion resistance, and cannot adapt to some special application environments. For example, under high temperature, high humidity and corrosive media, problems such as coating corrosion and shedding are prone to occur, which affects the service life of the product. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a continuous high-phosphorus chemical nickel plating method to solve the technical problem of insufficient stability of the plating solution in the prior art.

[0005] To achieve the above object, the technical solution adopted in the present application is: to provide a continuous high-phosphorus chemical nickel plating method, comprising the following steps: Preparing a chemical plating solution including a nickel salt, a complexing agent, and an additive; Adding a first reducing agent and a second reducing agent into the plating solution in a mass ratio of (3-5):(1-2), wherein the first reducing agent is a phosphate and / or phosphite organic compound, and the second reducing agent is one or more of lithium aluminum hydride, sodium borohydride, propionic acid or succinic acid; Adjust the pH value of the plating solution to 4.5-5.5; Control the temperature of the plating solution at 80-90°C; The substrate is placed in the plating solution for continuous plating operation.

[0006] In one embodiment, the first reducing agent is trimethyl phosphite or triethyl phosphite.

[0007] In one embodiment, the plating solution is configured according to the following components in mass ratio: Nickel salt 45%-60% First reducing agent 15%-25% Second reducing agent 5%-10% Complexing agent 12%-25% Additives 3%-5%.

[0008] In one embodiment, the additive is one or more of a buffer, a stabilizer, a wetting agent, a surfactant, and a brightener.

[0009] In one embodiment, the substrate is placed in a plating solution for continuous plating, and the plating solution is stirred by ultrasonic waves.

[0010] In one embodiment, the pH value of the plating solution is adjusted to 4.5-5.5, comprising: The pH value of the plating solution is monitored in real time by a pH sensor, and the acquired value is converted into an electrical signal and transmitted to a control system; When the pH value of the plating solution deviates from 4.5-5.5, the control system regulates the automatic dosing machine and the automatic titration device to accurately add the pH regulator to the plating solution.

[0011] In one embodiment, the pH regulator added to the plating solution is ammonia water or potassium carbonate.

[0012] In one embodiment, the temperature of the plating solution is controlled at 80-90° C., comprising: The temperature of the plating solution is monitored in real time by a temperature sensor, and the acquired value is converted into an electrical signal; The electrical signal is transmitted to the conditioning module for amplification and filtering and then transmitted to the control system; When the temperature of the plating solution deviates from the range of 80-90° C., the control system regulates the heating or cooling device to increase or decrease the temperature of the plating solution.

[0013] The beneficial effect of the continuous high-phosphorus chemical nickel plating method provided by the present application is that: compared with the prior art, the present application adopts a combination of a first reducing agent and a second reducing agent, wherein the first reducing agent is a phosphate and / or phosphite organic compound, and the first reducing agent can stably release active phosphorus atoms at a relatively low temperature, providing a rich phosphorus source for the coating, and ensuring that the coating reaches a high phosphorus content; the second reducing agent is one or more of lithium aluminum hydride, sodium borohydride, propionic acid or succinic acid, and the second reducing agent can effectively promote the reduction deposition process of nickel ions and accelerate the deposition rate. The two reducing agent components cooperate with each other, so that the plating solution maintains a high degree of stability during the continuous plating process, effectively suppresses the fluctuation of the plating solution components, and significantly improves the consistency and stability of the coating quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] Figure 1 A flow chart of a continuous high-phosphorus chemical nickel plating method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0016] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0017] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0018] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0019] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0020] See also Figure 1 , the continuous high-phosphorus chemical nickel plating method provided in the embodiment of the present application is now described. In this specification, "high phosphorus" means that the phosphorus content in the nickel plating layer is 9-14% (by weight). This high-phosphorus content plating layer has better corrosion resistance and lower hardness, and is suitable for applications requiring good corrosion resistance. The continuous high-phosphorus chemical nickel plating method comprises the following steps: Preparing a chemical plating solution including a nickel salt, a complexing agent, and an additive; Adding a first reducing agent and a second reducing agent to the plating solution in a mass ratio of (3-5):(1-2), wherein the first reducing agent is a phosphate and / or phosphite organic compound, and the second reducing agent is one or more of lithium aluminum hydride, sodium borohydride, propionic acid or succinic acid; Adjust the pH value of the plating solution to 4.5-5.5; Control the temperature of the plating solution at 80-90°C; The substrate is placed in the plating solution for continuous plating operation.

[0021] Specifically, the continuous high-phosphorus chemical nickel plating process needs to be equipped with special plating tanks, heaters, circulating pumps, filters and other equipment to ensure the stability and uniformity of the plating solution. First, a chemical plating solution containing components such as nickel salts, complexing agents, additives, etc. is configured according to the conventional process, wherein the nickel salt can be one or more of nickel sulfate, nickel chloride, nickel hypophosphite, nickel carbonate, and nickel acetate. The complexing agent can be one or more of glycolic acid, citric acid, lactic acid, malic acid, and succinic acid. The additive can be a stabilizer, a buffer, a surfactant, or a wetting agent. The various components such as nickel salts, complexing agents, and additives are mixed in a predetermined ratio and added to the plating tank. Two combinations of reducing agents are used, that is, the first reducing agent and the second reducing agent are mixed in a mass ratio of (3-5): (1-2) and added to the plating solution. The first reducing agent is a phosphate organic compound, a phosphite organic compound, or a mixture of the two. For example, the first reducing agent can be trimethyl phosphite or triethyl phosphite. Phosphate organic compounds and phosphite organic compounds have certain reducing properties, and can reduce nickel ions to nickel in the chemical nickel plating process, and release phosphorus atoms as a phosphorus source. The second reducing agent is one or more of lithium aluminum hydride, sodium borohydride, propionic acid or succinic acid. The second reducing agent can effectively promote the reduction and deposition process of nickel ions, accelerate the deposition rate, and thus quickly deposit a nickel-phosphorus alloy coating on the surface of the substrate. Then, the pH value of the plating solution needs to be adjusted to 4.5-5.5 by a pH value regulator. For example, the initial pH value of the plating solution is detected by a pH sensor. If the pH value deviates from the range of 4.5-5.5, an acidic or alkaline pH regulator needs to be added to the plating solution for adjustment. Before starting plating, the temperature of the plating solution needs to be heated to 80-90°C. For example, the plating solution can be heated to 80-90°C by a heating rod arranged in a plating tank. During the plating process, substrates such as aluminum alloy, stainless steel, carbon and alloy steel, copper alloy and non-conductive materials are placed in the plating solution for continuous plating operations.

[0022] During the entire process, the pH value of the plating solution must always be controlled within the range of 4.5-5.5, and the temperature of the plating solution must be controlled within the range of 80-90°C to ensure the quality and performance of the coating. In addition, as the plating process progresses, the concentrations of core components such as nickel ions, reducing agents, and complexing agents will gradually decrease. In order to ensure the quality and stability of the coating, it is necessary to monitor the concentrations of core components such as nickel ions, reducing agents, and complexing agents in the plating solution in real time; when the concentrations of core components such as nickel ions, reducing agents, and complexing agents do not meet the set values, the corresponding components need to be added to the plating solution in a timely manner. ‌‌ Compared with the prior art, the present application adopts a combination of a first reducing agent and a second reducing agent, wherein the first reducing agent is a phosphate and / or phosphite organic compound, the first reducing agent can stably release active phosphorus atoms at a relatively low temperature, provide a rich phosphorus source for the coating, and ensure that the coating reaches a high phosphorus content; the second reducing agent is one or more of lithium aluminum hydride, sodium borohydride, propionic acid or succinic acid, and the second reducing agent can effectively promote the reduction deposition process of nickel ions and accelerate the deposition rate. The two reducing agent components cooperate with each other, so that the plating solution maintains a high degree of stability during the continuous plating process, effectively suppresses the fluctuation of the plating solution components, and significantly improves the consistency and stability of the coating quality.

[0023] In one embodiment, the first reducing agent is trimethyl phosphite or triethyl phosphite. Trimethyl phosphite and triethyl phosphite have strong reducing properties, can effectively provide electrons in the continuous high-phosphorus chemical nickel plating reaction, and promote the reduction of nickel ions; during the reaction, trimethyl phosphite and triethyl phosphite can chelate with nickel ions to avoid unnecessary side reactions, thereby improving the accuracy and efficiency of the reaction, ensuring uniform deposition of nickel, and avoiding the generation of impurities or affecting the quality of the coating. In addition, trimethyl phosphite and triethyl phosphite are relatively stable at room temperature and pressure, and can maintain a long service life in the continuous high-phosphorus chemical nickel plating reaction.

[0024] In one embodiment, the plating solution is configured according to the following mass ratios: nickel salt 45%-60%, first reducing agent 15%-25%, second reducing agent 5%-10%, complexing agent 12%-25%, additive 3%-5%. Among them, nickel salt occupies a large proportion as the main nickel source, ensuring the main component of nickel in the coating. The first reducing agent, as the main reducing agent, reduces nickel ions to metallic nickel during the chemical nickel plating process. The second reducing agent, as another reducing agent, acts together with the first reducing agent to promote the reduction of nickel ions. The complexing agent is used to stabilize the nickel ions in the plating solution to prevent them from hydrolysis or precipitation, and also helps to adjust the composition and structure of the coating. The additives can be surfactants, stabilizers, brighteners, buffers, etc., which are used to improve the appearance, uniformity or other properties of the coating. Since the content of the first reducing agent as a phosphorus source is relatively large (15%-25%), the coating prepared using the plating solution of this configuration has a high phosphorus content and has excellent properties such as corrosion resistance and wear resistance. The chemical nickel plating process is controllable, which helps to obtain stable and predictable coating quality and performance.

[0025] In one embodiment, the additive is one or more of a buffer, a stabilizer, a wetting agent, a surfactant, and a brightener. The buffer and stabilizer help improve the uniformity of the coating, the brightener helps improve the appearance of the coating, and the surfactant and wetting agent help improve the wettability of the plating solution, making it easier for the plating solution to wet the surface of the substrate, thereby improving the adhesion and uniformity of the coating. In addition, the surfactant can also improve the fluidity of the plating solution, help the plating solution to be more evenly distributed on the surface of the substrate, and further improve the uniformity and density of the coating.

[0026] In one embodiment, the substrate is placed in a plating solution for continuous plating, and the plating solution is stirred by ultrasonic waves. Specifically, during the plating process, compared with the traditional mechanical stirring method, the ultrasonic stirring method promotes the uniform dispersion of the reducing agent and other components in the plating solution through the cavitation effect of the ultrasonic wave, which helps to improve the uniformity of the plating layer.

[0027] In one embodiment, the pH value of the plating solution is adjusted to 4.5-5.5, comprising: The pH value of the plating solution is monitored in real time by a pH sensor, and the acquired value is converted into an electrical signal and transmitted to a control system; When the pH value of the plating solution deviates from 4.5-5.5, the control system regulates the automatic dosing machine and the automatic titration device to accurately add the pH regulator to the plating solution.

[0028] In the production process of continuous high-phosphorus chemical nickel plating, a pH sensor can be installed in the plating tank, and the pH sensor is connected to the control system. In addition, an automatic dosing machine for adding pH regulators and other ingredients to the plating tank needs to be installed next to the plating tank. The pH sensor monitors the pH value of the chemical plating solution in the plating tank in real time, and converts the obtained value into an electrical signal and transmits it to the control system. The control system compares the real-time acquired pH data with the preset value. When the pH value of the plating solution deviates from the range of 4.5-5.5, the control system issues an instruction to add pH regulators to the plating solution by regulating the automatic dosing machine, and accurately controls the amount of pH regulator added by the automatic titration device.

[0029] In one embodiment, the pH regulator added to the plating solution is ammonia water or methyl carbonate. Ammonia water has a buffering capacity and can effectively control the pH of the plating solution to prevent the plating solution from being hydrolyzed or causing the stability of the plating solution to decrease due to excessively high or low pH. The wastewater produced by adjusting the pH value of potassium carbonate has less pollution to the environment and is more environmentally friendly.

[0030] In one embodiment, the temperature of the plating solution is controlled at 80-90° C., comprising: The temperature of the plating solution is monitored in real time by a temperature sensor, and the acquired value is converted into an electrical signal; The electrical signal is transmitted to the conditioning module for amplification and filtering and then transmitted to the control system; When the temperature of the plating solution deviates from the range of 80-90° C., the control system regulates the heating or cooling device to increase or decrease the temperature of the plating solution.

[0031] In the production process of continuous high-phosphorus chemical nickel plating, a temperature sensor, a heating device and a cooling device can be installed in the plating tank, and the temperature sensor, the heating device and the cooling device are all connected to the control system. A conditioning module is also connected between the temperature sensor and the control system. The temperature sensor monitors the temperature of the plating solution in real time, and converts the obtained value into an electrical signal, and then transmits the electrical signal to the conditioning module, which amplifies and filters the obtained electrical signal and then transmits it to the control system. The control system compares the obtained real-time temperature data with the preset value. When the temperature of the plating solution deviates from the range of 80-90, the control system adjusts the heating or cooling device to heat or cool the plating solution, so that the temperature of the plating solution is maintained within the range of 80-90℃. Example

[0032] A continuous high-phosphorus chemical nickel plating method comprising: Add nickel sulfate, citric acid and ammonium chloride to the plating tank in the following mass ratios: 50% nickel sulfate, 18% trimethyl phosphite, 5% sodium borohydride, 22% citric acid and 5% ammonium chloride; Adding trimethyl phosphite and sodium borohydride into the plating tank to prepare a predetermined amount of plating solution; The pH value of the plating solution is measured by a pH sensor, and the pH value of the plating solution is adjusted to 5 by adding a pH regulator; The temperature of the plating solution is heated to 80-90°C by a heating device; The substrate is placed in a plating solution for continuous plating, and the temperature of the plating solution is continuously monitored by a temperature sensor. When the temperature of the plating solution deviates from 80-90° C., the plating solution is heated or cooled by a heating device or a cooling device to maintain the temperature of the plating solution at 80-90° C.; and the pH value of the plating solution is continuously monitored by a pH sensor. When the pH value of the plating solution deviates from the range of 4.5-5.5, a pH regulator is added to the plating solution to maintain the pH value of the plating solution within the range of 4.5-5.5. Example

[0033] A continuous high-phosphorus chemical nickel plating method comprising: Add nickel sulfate, citric acid and ammonium chloride into the plating tank according to the mass ratio of 46% nickel sulfate, 22% triethyl phosphite, 8% lithium aluminum hydride, 19% citric acid and 5% ammonium chloride; Adding triethyl phosphite and lithium aluminum hydride into the plating tank to prepare a predetermined amount of plating solution; The pH value of the plating solution is measured by a pH sensor, and the pH value of the plating solution is adjusted to 5 by adding a pH regulator; The temperature of the plating solution is heated to 80-90°C by a heating device; The substrate is placed in a plating solution for continuous plating, and the temperature of the plating solution is continuously monitored by a temperature sensor. When the temperature of the plating solution deviates from 80-90° C., the plating solution is heated or cooled by a heating device or a cooling device to maintain the temperature of the plating solution at 80-90° C.; and the pH value of the plating solution is continuously monitored by a pH sensor. When the pH value of the plating solution deviates from the range of 4.5-5.5, a pH regulator is added to the plating solution to maintain the pH value of the plating solution within the range of 4.5-5.5. Example

[0034] A continuous high-phosphorus chemical nickel plating method comprising: Add nickel sulfate, citric acid and ammonium chloride to the plating tank in the following mass ratios: 53% nickel sulfate, 16% trimethyl phosphite, 10% lithium aluminum hydride, 17% citric acid and 4% ammonium chloride; Adding trimethyl phosphite and lithium aluminum hydride into the plating tank to prepare a predetermined amount of plating solution; The pH value of the plating solution is measured by a pH sensor, and the pH value of the plating solution is adjusted to 5 by adding a pH regulator; The temperature of the plating solution is heated to 80-90°C by a heating device; The substrate is placed in a plating solution for continuous plating, and the temperature of the plating solution is continuously monitored by a temperature sensor. When the temperature of the plating solution deviates from 80-90° C., the plating solution is heated or cooled by a heating device or a cooling device to maintain the temperature of the plating solution at 80-90° C.; and the pH value of the plating solution is continuously monitored by a pH sensor. When the pH value of the plating solution deviates from the range of 4.5-5.5, a pH regulator is added to the plating solution to maintain the pH value of the plating solution within the range of 4.5-5.5. Example

[0035] A method for continuous high-phosphorus chemical nickel plating, comprising: Add nickel sulfate, citric acid and ammonium chloride into the plating tank in the following mass ratios: 50% nickel sulfate, 18% triphenyl phosphite, 5% sodium borohydride, 22% citric acid and 5% ammonium chloride; Adding triphenyl phosphite and sodium borohydride into the plating tank to prepare a predetermined amount of plating solution; The pH value of the plating solution is measured by a pH sensor, and the pH value of the plating solution is adjusted to 5 by adding a pH regulator; The temperature of the plating solution is heated to 80-90°C by a heating device; The substrate is placed in a plating solution for continuous plating, and the temperature of the plating solution is continuously monitored by a temperature sensor. When the temperature of the plating solution deviates from 80-90° C., the plating solution is heated or cooled by a heating device or a cooling device to maintain the temperature of the plating solution at 80-90° C.; and the pH value of the plating solution is continuously monitored by a pH sensor. When the pH value of the plating solution deviates from the range of 4.5-5.5, a pH regulator is added to the plating solution to maintain the pH value of the plating solution within the range of 4.5-5.5. Example

[0036] A method for continuous high-phosphorus chemical nickel plating, comprising: Add nickel sulfate, citric acid and ammonium chloride into the plating tank in the following mass ratios: 50% nickel sulfate, 18% trimethyl phosphite, 5% propionic acid, 22% citric acid and 5% ammonium chloride; Adding trimethyl phosphite and propionic acid into the plating tank to prepare a predetermined amount of plating solution; The pH value of the plating solution is measured by a pH sensor, and the pH value of the plating solution is adjusted to 5 by adding a pH regulator; The temperature of the plating solution is heated to 80-90°C by a heating device; The substrate is placed in a plating solution for continuous plating, and the temperature of the plating solution is continuously monitored by a temperature sensor. When the temperature of the plating solution deviates from 80-90° C., the plating solution is heated or cooled by a heating device or a cooling device to maintain the temperature of the plating solution at 80-90° C.; and the pH value of the plating solution is continuously monitored by a pH sensor. When the pH value of the plating solution deviates from the range of 4.5-5.5, a pH regulator is added to the plating solution to maintain the pH value of the plating solution within the range of 4.5-5.5.

[0037] According to the above five embodiments, the same substrate is plated, and the phosphorus content of the obtained coating is as follows: From the above examples, it is found that in Example 4, since triphenyl phosphite is used as the first reducing agent, the reducing property of triphenyl phosphite is inferior to trimethyl phosphite or triethyl phosphite. Therefore, although the phosphorus content of the coating obtained in Example 4 is also high, the stability of the plating solution is worse than that of the other examples. After 80 hours of continuous plating, the plating solution becomes turbid. In Example 5, propionic acid is used as the second reducing agent, and the deposition rate of the obtained coating is reduced, resulting in an extension of the overall plating time. However, the phosphorus content of the coating is still higher than that of the coating obtained by the prior art, so the corrosion resistance of the coating is still better than that of the prior art.

[0038] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A continuous high-phosphorus chemical nickel plating method, characterized in that: The following steps are involved: Preparing a chemical plating solution including a nickel salt, a complexing agent, and an additive; Adding a first reducing agent and a second reducing agent to the plating solution in a mass ratio of (3-5):(1-2), wherein the first reducing agent is a phosphate and / or phosphite organic compound, and the second reducing agent is one or more of lithium aluminum hydride, sodium borohydride, propionic acid or succinic acid; Adjust the pH value of the plating solution to 4.5-5.5; Control the temperature of the plating solution at 80-90°C; The substrate is placed in the plating solution for continuous plating operation.

2. The continuous high-phosphorus chemical nickel plating method according to claim 1, wherein: The first reducing agent is trimethyl phosphite or triethyl phosphite.

3. The continuous high-phosphorus chemical nickel plating method according to claim 1, wherein: The plating solution is configured according to the following components in mass ratio: Nickel salt 45%-60% First reducing agent 15%-25% Second reducing agent 5%-10% Complexing agent 12%-25% Additives 3%-5%.

4. The continuous high-phosphorus chemical nickel plating method according to claim 1, wherein: The additive is one or more of a buffer, a stabilizer, a wetting agent, a surfactant, and a brightener.

5. The continuous high-phosphorus chemical nickel plating method according to any one of claims 1 to 4, characterized in that: The substrate is placed in a plating solution for continuous plating, and the plating solution is stirred by ultrasonic waves.

6. The continuous high-phosphorus chemical nickel plating method according to any one of claims 1 to 4, characterized in that: Adjust the pH value of the plating solution to 4.5-5.5, including: The pH value of the plating solution is monitored in real time by a pH sensor, and the acquired value is converted into an electrical signal and transmitted to a control system; When the pH value of the plating solution deviates from 4.5-5.5, the control system regulates the automatic dosing machine and the automatic titration device to accurately add the pH regulator into the plating solution.

7. The continuous high-phosphorus chemical nickel plating method according to claim 6, wherein: The pH regulator added to the plating solution is ammonia water or potassium carbonate.

8. The continuous high-phosphorus chemical nickel plating method according to any one of claims 1 to 4, characterized in that: The temperature of the plating solution is controlled at 80-90°C, including: The temperature of the plating solution is monitored in real time by a temperature sensor, and the acquired value is converted into an electrical signal; The electrical signal is transmitted to the conditioning module for amplification and filtering and then transmitted to the control system; When the temperature of the plating solution deviates from the range of 80-90° C., the control system regulates the heating or cooling device to increase or decrease the temperature of the plating solution.

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