A method for high quality, defect free electroforming of nickel on the surface of an aluminum alloy component

Abstract

The present application relates to a kind of high-quality nickel electroforming methods without omission on the surface of aluminum alloy parts, belong to electroforming technical field.The present application specifically relates to a kind of dense, high-quality and surface without omission electroformed nickel material prepared on the surface of aluminum alloy by using chemical nickel plating and electroforming technology.The characteristics are that a layer of high-quality, uniform, dense chemical nickel plating layer is formed on the surface of aluminum alloy by using chemical nickel plating technology, electroforming tooling and electric connection point connection mode design are used, electroformed nickel process parameters are controlled, all parts on the surface of aluminum alloy parts can be deposited electroformed nickel layer, so that electroformed nickel coating with stable composition, dense structure, excellent surface quality, higher bonding strength and certain thickness is obtained.

Description

Technical Field

[0001] This invention belongs to the field of electroforming technology, specifically relating to a method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts. Background Technology

[0002] Semiconductor equipment components are a crucial link in semiconductor equipment manufacturing, and their market size continues to expand along with the growth of the global semiconductor equipment market. However, with increasingly fierce trade frictions and strict foreign restrictions on the semiconductor equipment industry, the demand for domestic substitution of semiconductor equipment is extremely urgent. Leading domestic semiconductor manufacturers have taken the lead in developing silicon thin-film epitaxy equipment and have made breakthroughs in key technologies such as multi-channel, multi-zone advection gas distribution technology for silicon epitaxy process chambers, multi-zone infrared heating modules and temperature control technology, "EPI vision" high-temperature visualization monitoring technology, and high-cleanliness chamber control technology. Among these, gold-plated products are the core components in the infrared heating module temperature control. By mirror polishing the material surface and then plating with nickel and gold, a mirror reflectivity of up to 97% is achieved. With combinations of gold-plated parts of various shapes, the combined reflection of infrared rays emitted by each heating lamp enables the adjustment and control of heating temperature and range, forming a controllable temperature field while simultaneously providing cooling.

[0003] Foreign semiconductor epitaxial equipment typically uses gold-plated components made from aluminum alloy parts through processing, polishing, nickel plating, and then gold plating. These components require extremely high precision in shape and position, reliability, surface quality, and reflectivity. Therefore, all gold-plated components must have a complete, unblemished gold layer, achieving a surface finish at the nanometer level. With the domestic substitution of semiconductor equipment, to ensure the overall process performance and specifications of the equipment, the surface quality and performance of gold-plated components must meet the requirements of foreign competitors. However, current domestic requirements for nickel and gold plating on aluminum alloy surfaces are far below current semiconductor industry standards. Surface defects such as pitting, pinholes, hard protrusions, and missing nickel plating at electroplated connection points significantly affect the surface quality and reflectivity of subsequent gold plating. Therefore, for novel aluminum alloy components used in semiconductors, there is an urgent need to research a high-quality, residue-free electroplating nickel method. This method should improve the surface quality of the electroplated nickel layer and the integrity of the plating at electrical connection points while ensuring the thickness of the electroplated nickel layer, in order to meet the high-quality surface requirements of nanometer-level smoothness and 97% reflectivity for subsequent gold plating. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned defects of the prior art and provide a method for high-quality, complete electroplating nickel on the surface of aluminum alloy parts. This method involves preparing a uniform, dense, and highly adhesive electroless nickel plating layer on the surface of the aluminum alloy; and then performing an activation pretreatment on the electroless nickel plating layer to achieve high-quality electroplating nickel forming on the surface of the aluminum alloy parts.

[0005] The above-mentioned objectives of the present invention are mainly achieved through the following technical solutions: A method for electroforming nickel onto the surface of aluminum alloy parts without any omissions includes the following steps: (1) Pre-treatment of aluminum alloy parts, the pre-treatment including ultrasonic degreasing, alkaline etching and brightening; (2) The pretreated aluminum alloy parts obtained in step (1) are first immersed in zinc, then dezincified, cleaned and then immersed in zinc a second time. (3) The aluminum alloy parts obtained in step (2) are subjected to alkaline pre-plating of nickel, followed by chemical nickel plating; (4) Degreasing and activation pretreatment are performed on the nickel-plated aluminum alloy parts obtained in step (3); (5) Electroform nickel onto the aluminum alloy parts obtained in step (4).

[0006] In step (1), the degreasing solution for ultrasonic degreasing includes 30~50g / L HS-58 cleaning agent and the remainder water. The ultrasonic degreasing process is ultrasonic degreasing at 15~40℃ for 10-30min.

[0007] In step (1), the alkaline etching solution of the alkaline etching process includes 20~30g / L sodium carbonate, 10~20g / L sodium hydroxide, 20~30g / L sodium phosphate and the balance water. The alkaline etching process is to etch at 50~70℃ for 1-3 minutes. The light extraction solution for the light extraction process includes 30-50 g / L micro-etching salt, 10-20 ml / L sulfuric acid, and the remainder water. The light extraction process is performed at room temperature for 3-10 minutes.

[0008] In step (2), the zinc immersion solution includes sodium hydroxide with a mass fraction of 5-15%, sodium cyanide with a mass fraction of 0-0.5%, nickel sulfate with a mass fraction of 1-5%, and the balance water; the zinc stripping solution includes 30-50 g / L micro-etching salt and the balance water; the first zinc immersion time is 30-60 s, and the second zinc immersion time is 20-40 s.

[0009] In step (3), the alkaline pre-plating nickel solution includes 20-25 g / L nickel sulfate, 20-25 g / L sodium hypophosphite, 25-35 g / L sodium lactate, 10-20 ml / L triethanolamine, 20-30 g / L ammonia and the balance water. The pH of the alkaline pre-plating nickel solution is adjusted with dilute sulfuric acid or ammonia, with a pH range of 9.5-10.5. The solution temperature is 20-35℃, and the pre-plating time is 3-5 min.

[0010] In step (3), the acidic electroless nickel plating solution includes 20-30 g / L nickel sulfate, 20-30 g / L sodium hypophosphite, 25-35 ml / L lactic acid, 2-3 ml / L propionic acid and the balance water. The pH value of the acidic electroless nickel plating solution is in the range of 4.6-4.8, the temperature is 88-92℃, and the electroless nickel plating time is 0-90 min.

[0011] In step (4), the degreasing agent is HS-58 with a concentration of 30-50 g / L, the degreasing agent temperature is 15-40℃, and the degreasing time is 10-30 min; the activation solution includes 60-100 g / L micro-etching salt, 10-20 ml / L sulfuric acid and the remainder water, the activation temperature is room temperature, and the activation time is 3-5 min.

[0012] In step (5), the electroforming solution comprises 250-400 g / L nickel sulfamate, 20-45 g / L boric acid, 15-25 g / L nickel chloride, and the remainder water. The pH of the electroforming solution is adjusted to 4-4.5 using sulfamate. The electroforming temperature is 28-32℃, and the electroforming current density is 0.5-1.5 A / dm³. 2 The coating thickness is 20~200 μm. During the electroforming process, the cathode rotates at a speed of 3~20 r / min or the surface of the aluminum alloy parts is flushed by a circulating liquid flow.

[0013] In step (5), the electrical connection point of the electroformed nickel is a threaded hole or a through hole, and the tooling material for the electroformed nickel includes at least one of aluminum alloy, stainless steel, copper alloy or titanium alloy.

[0014] An aluminum alloy component is electroformed with nickel according to the method described above.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects: (1) This invention provides a pretreatment solution system with low corrosivity and uniform treatment for the surface of high-precision aluminum alloy mirror products. It adopts secondary chemical nickel plating and alkaline pre-plating to reduce the impact of zinc immersion on subsequent processes and improve the stability of nickel plating solution.

[0016] (2) In the embodiments of the present invention, the brightening solution and zinc stripping solution are preferably treated with micro-etching salt, which has excellent effect and is environmentally friendly and pollution-free. The zinc immersion solution has stable performance and high coating adhesion, which is beneficial to the subsequent preparation of electro-cast nickel. The acidic electroless nickel plating solution uses lactic acid and a small amount of propionic acid as complexing agents to prevent solution decomposition and effectively control the deposition rate. The obtained electroless nickel plating layer has a smooth, dense, uniform thickness, stable composition and excellent performance.

[0017] (3) The preferred electrical connection method of the present invention can avoid surface defects such as pinholes and pits during the electroforming process of the product, and can also achieve effective connection at the connection point, so as to achieve complete electroforming of nickel on the product surface, avoid poor conductivity and uneven plating thickness due to poor contact, and the electroforming solution system used is stable, the process is simple and easy to operate, and has great potential for engineering application. Attached Figure Description

[0018] Figure 1This is a process flow diagram of the process for leaving no residual electroplated nickel on the surface of aluminum alloy parts according to the present invention; Figure 2 This is a schematic diagram of the component connection fixture in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the through-hole component connection fixture in Embodiment 2 of the present invention. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments: like Figure 1 As shown, a method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts includes the following steps: (1) Design electroforming nickel tooling and electrical connection point connection methods for the product structure; (2) The product is pretreated by ultrasonic degreasing and alkaline etching, and then subjected to a second zinc immersion. (3) After alkaline pre-plating nickel, chemical nickel plating is carried out using a medium-high phosphoric acid nickel plating solution system, and the solution composition, temperature and pH value are controlled within the process range. (4) Loading and pre-treating the nickel-plated products by degreasing and activation; (5) Control the process parameters such as solution temperature, pH value and current density, and perform electroforming of nickel in aminosulfonate solution.

[0020] In the above-mentioned high-quality, complete electroplating nickel technology for aluminum alloy surfaces, step (1) involves designing electroplating nickel fixtures and electrical connection methods for the product structure. The design principle of the electroplating nickel fixture is based on the product structure, size, weight, and plating appearance requirements. Typically, the electroplating nickel fixture should be connected to the cathode rotating shaft or moving shaft to ensure that the product moves during the electroplating process and prevent porosity. Therefore, the upper end of the fixture and the moving shaft should be easy to install and remove. At the same time, considering the tank size and product structure, the electroplating nickel fixture structure is designed, requiring a stable structure, excellent load-bearing capacity, and that the fixture material does not react with the solution and has stable performance. In addition, protective coatings can be applied to parts of the fixture that do not require conductivity, which is beneficial for repeated use of the fixture without corrosion or damage. For electrical connection points on the product surface, the selection rules should also be based on the product structure and plating appearance requirements. Generally, they should be selected in non-working areas such as threaded holes, through holes, or areas where electroplating is not required. For products with threaded holes, screw connection is preferred to ensure that the product connection points are fixed and have good conductivity. When a product has only through holes, it is not directly electroplated with nickel after chemical nickel plating. Instead, it is remounted to determine the conductive points. For small, lightweight electroplated parts, hanging through the through holes is sufficient. When the electroplated parts are large and heavy, a combination of washers, screws, and nuts is used for conductivity and fixation.

[0021] In step (2), the degreasing solution consists of 30-50 g / L HS-58 cleaning agent and the remainder water; the alkaline etching solution consists of 20-30 g / L sodium carbonate, 10-20 g / L sodium hydroxide, 20-30 g / L sodium phosphate and the remainder water; the brightening solution consists of 30-50 g / L micro-etching salt, 10-20 ml / L sulfuric acid and the remainder water; and the zinc immersion solution consists of 5-15% sodium hydroxide, 0-0.5% sodium cyanide, and 1-5% nickel sulfate. The zinc stripping solution consists of 30-50 g / L micro-etching salt and residual water. All chemicals used are of analytical grade. The degreasing temperature should be 15-40℃ for 10-30 min, the alkaline etching temperature should be 50-70℃ for 1-3 min, the brightening temperature should be room temperature for 3-10 min, and the zinc immersion and stripping should be done at room temperature for 20-60 s. Each process must be rinsed thoroughly with tap water and deionized water. In step (3), the alkaline pre-plating nickel solution consists of 20-25 g / L nickel sulfate, 20-25 g / L sodium hypophosphite, 25-35 g / L sodium lactate, 10-20 ml / L triethanolamine, 20-30 g / L ammonia, and the remainder water. The pH is adjusted with dilute sulfuric acid or ammonia and controlled at 9.5-10.5. The solution temperature is 20-35℃, and the pre-plating time is 3-5 minutes. The acidic electroless nickel plating solution consists of 20-30 g / L nickel sulfate, 20-30 g / L sodium hypophosphite, 25-35 ml / L lactic acid, 2-3 ml / L propionic acid, and the remainder water. The pH is 4.6-4.8, the solution temperature is 88-92℃, and the electroless nickel plating time is usually 0-90 minutes or controlled according to the usage requirements.

[0022] In step (4), the nickel plating product usually refers to a part with a through hole but no threaded hole. When the product is electroplated after electroplating, the degreasing method is the same as in step (1). The degreasing is to use 30~50g / L HS-58 degreasing agent to immerse the cathode at 15~40℃ for 10~30min. In step (4), the activation solution is composed of 60-100 g / L micro-etching salt, 10-20ml / L sulfuric acid and the remainder water. It is soaked at room temperature for 3-5min. In step (5), the electroforming solution uses an aminosulfonate solution system. The solution composition is 250~400 g / L nickel aminosulfonate, 20~45 g / L boric acid, 15~25 g / L nickel chloride, with the balance being water. The pH value is adjusted using aminosulfonate, ranging from 4 to 4.5. All reagents used are of analytical grade. The electroforming solution temperature is 28~32℃, and the current density is 0.5~1.5 A / dm³. 2 The electroforming time is designed based on the coating thickness by calculating the amount of electricity applied, and the coating thickness is usually 20~200 μm.

[0023] In the above-mentioned electroforming nickel technology that leaves no trace on the aluminum alloy surface, during the electroforming process in step (5), the cathode needs to be rotated at a speed of 3 to 20 r / min or the surface needs to be flushed by a circulating liquid flow.

[0024] Example 1 The aluminum alloy components were electroplated with nickel without any omissions. The cathode used an aluminum alloy component with threaded holes, with a surface area of ​​approximately 14 dm². 2 After electroless nickel plating, the product undergoes electroforming nickel in a nickel sulfamate solution. The steps include: designing electroforming nickel fixtures and electroforming nickel electrical connection methods based on the product structure; performing ultrasonic degreasing, alkaline etching, and other pretreatments on the product, followed by a second zinc immersion; performing acidic electroless nickel plating after alkaline pre-plating; electroforming nickel; and rinsing with water and removing the fixtures.

[0025] The first step is the design of electroforming nickel tooling and electrical connection methods. For the product's disc shape and the uniformly distributed threaded holes around its circumference, an electroformed nickel tooling made of aluminum alloy was designed, as shown in the attached document. Figure 2 As shown, the T-shaped structure is integrally machined. The two ends of the crossbar are designed with connecting grooves corresponding to the thread hole size. The two ends of the crossbar are connected to the product with stainless steel screws as electrical connection points. The upper end of the vertical bar is designed with connecting holes, which can be connected to the electroforming rotating shaft with screws to ensure uniform rotation of the product during the electroforming process. The second step involves pretreatment of the product, including ultrasonic degreasing and alkaline etching. The product is ultrasonically degreased for 20 minutes in a degreasing solution containing 50 g / L HS-58 cleaning agent at 40°C. Then, it is alkali etched for 2 minutes in an alkaline etching solution containing 20 g / L sodium carbonate, 10 g / L sodium hydroxide, and 20 g / L sodium phosphate at 60°C. After alkaline etching, it is brightened for 5 minutes in a brightening solution containing 40 g / L micro-etching salt and 15 ml / L sulfuric acid at room temperature. Then, it is immersed in zinc for 55 seconds in a zinc immersion solution containing 10% sodium hydroxide, 0.5% sodium cyanide, and 5% nickel sulfate at room temperature. After zinc immersion, it is stripped in zinc stripping solution containing 40 g / L micro-etching salt at room temperature for 40 seconds. Finally, it is immersed in zinc for 20 seconds in a second zinc immersion solution, which is the same as the first zinc immersion solution. Each process must be rinsed with tap water and deionized water respectively. The third step involves alkaline pre-plating followed by acidic electroless nickel plating. After pretreatment, electroless nickel plating is performed. The alkaline pre-plating solution consists of 25 g / L nickel sulfate, 25 g / L sodium hypophosphite, 30 g / L sodium lactate, 15 ml / L triethanolamine, 25 g / L ammonia, and the remainder water. The pH is adjusted to 10, the solution temperature is 30℃, and the pre-plating time is 4 min. After pre-plating, acidic electroless nickel plating is performed. The solution consists of 25 g / L nickel sulfate, 25 g / L sodium hypophosphite, 35 ml / L lactic acid, 2 ml / L propionic acid, and the remainder water. The pH is 4.8, the solution temperature is 90℃, and the electroless nickel plating time is 60 min.

[0026] Step 4, electroforming nickel After rinsing off the electroless nickel plating solution, electroforming nickel is performed directly. The electroforming solution uses an aminosulfonate solution system containing 350 g / L nickel aminosulfonate, 35 g / L boric acid, and 20 g / L nickel chloride. The pH is adjusted to 4.5 with aminosulfonate. The electroforming solution temperature is 30℃, and the current density is 1 A / dm³. 2 The cathode rotation speed is 10 r / min.

[0027] Step 5: Wash with water and demold. Electroforming for 6 hours, then turn off the rotating fixture and rectifier, remove the product from the solution, rinse off any remaining electroforming solution, clean the product surface and screw connection areas, remove the screws, and clean the product with tap water and deionized water.

[0028] Upon inspection of the product surface, the nickel plating is dark gray in color, smooth, and free of defects such as pinholes and nodules. The nickel plating layer on the product surface is complete and without omissions. The threaded holes of the electrical connection points are smooth and retain their original metallic color. The nickel plating layer around the connection points is complete.

[0029] Example 2 The aluminum alloy component surface is treated with electroplating nickel without any omissions. The cathode uses an aluminum alloy component with no threaded holes, only through holes, and has a surface area of ​​approximately 1 dm². 2 After electroless nickel plating, the product undergoes electroforming nickel in a nickel sulfamate solution. The steps include: designing electroforming nickel fixtures and electroforming nickel electrical connection methods based on the product structure; performing ultrasonic degreasing, alkaline etching, and other pretreatments on the product, followed by a second zinc immersion; performing acidic electroless nickel plating after alkaline pre-plating; mounting and degreasing and activation pretreatment on the electroless nickel product; electroforming nickel; and rinsing and removing the fixtures.

[0030] The first step is the design of electroforming nickel tooling and electrical connection methods. like Figure 3 As shown, for aluminum alloy products with a large quantity, small size, and only through holes, an electroforming nickel fixture made of copper alloy and stainless steel is designed. The fixture skeleton consists of a copper alloy spindle, a multi-layer ring support, and connecting rods. The outer surface, except for the conductive part at the top of the spindle, is coated with protective paint. Stainless steel wires with a diameter similar to the product's through hole connection point are evenly distributed on the outside of the ring support, serving as the product mounting and conductive parts. The top of the spindle is connected to the electroforming rotating shaft to ensure uniform rotation of the product during the electroforming process. The second step involves pretreatment of the product, including ultrasonic degreasing and alkaline etching. During pretreatment, the product is first hung on aluminum wire, ensuring the hanging points are loose and the product is easy to move. It is then ultrasonically degreased for 30 minutes in a degreasing solution containing 30g / L HS-58 cleaning agent at 30℃. Next, it undergoes alkaline etching for 1 minute in an alkaline etching solution containing 25g / L sodium carbonate, 15g / L sodium hydroxide, and 25g / L sodium phosphate at 50℃. After alkaline etching, it is brightened for 3 minutes in a brightening solution containing 30g / L micro-etching salt and 10ml / L sulfuric acid at room temperature. Then, it undergoes a first zinc immersion for 40 seconds in a zinc immersion solution containing 5% sodium hydroxide, 0.2% sodium cyanide, and 1% nickel sulfate at room temperature. After zinc immersion, it undergoes zinc stripping for 30 seconds in a zinc stripping solution containing 30g / L micro-etching salt at room temperature. Finally, it undergoes a second zinc immersion for 25 seconds in the same zinc immersion solution as the first immersion. Each step requires thorough rinsing with tap water and deionized water between processes. The third step involves alkaline pre-plating followed by acidic electroless nickel plating. After pretreatment, electroless nickel plating is performed. The alkaline pre-plating nickel solution consists of 20 g / L nickel sulfate, 20 g / L sodium hypophosphite, 35 g / L sodium lactate, 10 ml / L triethanolamine, 20 g / L ammonia, and the remainder water. The pH is adjusted to 10.5, the solution temperature is 25℃, and the pre-plating time is 5 min. After pre-plating, acidic electroless nickel plating is performed. The solution consists of 20 g / L nickel sulfate, 20 g / L sodium hypophosphite, 25 ml / L lactic acid, 3 ml / L propionic acid, and the remainder water. The pH is 4.6, the solution temperature is 89℃, and the electroless nickel plating time is 75 min. During the electroless nickel plating process, the workpiece is moved at the cathode and the solution is circulated to ensure uniform nickel plating at the plating points.

[0031] The fourth step is to load and pre-treat the nickel plating products by degreasing and activation. After electroless nickel plating, the aluminum wire is removed and the product is cleaned. The product is then mounted on an electroforming fixture, and the stainless steel wire ends are insulated with rubber sleeves to ensure the workpiece does not detach during electroforming and can be removed immediately afterward. After mounting, the product is degreased using a degreasing solution containing 40 g / L HS-58, immersed at 40°C for 20 minutes. After cleaning, it is immersed in an activating solution containing 80 g / L micro-etching salt and 15 ml / L sulfuric acid at room temperature for 4 minutes. Step 5, electroforming nickel After activation and rinsing, nickel electroforming is performed. The electroforming solution uses an aminosulfonate solution system containing 300 g / L nickel aminosulfonate, 30 g / L boric acid, and 15 g / L nickel chloride. The pH is adjusted to 4.1 with aminosulfonate. The electroforming solution temperature is 30℃, and the current density is 0.5 A / dm³. 2 The cathode rotation speed is 3 r / min.

[0032] Step 6: Wash with water and demold. Electroforming for 8 hours, then turn off the rotating fixture and rectifier, remove the product from the solution, rinse off any remaining electroforming solution, remove the protective sleeve from the stainless steel wire end, unload the product and clean it with tap water and deionized water.

[0033] Upon inspection of the product surface, the nickel plating is dark gray in color, smooth, and free of defects such as pinholes and nodules. The nickel plating on the product surface is complete and without omissions, and the nickel plating on the surface of the connection holes at the electrical connection points is also complete.

[0034] The above description is only the best specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the protection scope of the present invention.

[0035] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts, characterized in that: Includes the following steps: (1) Pre-treatment of aluminum alloy parts, the pre-treatment including ultrasonic degreasing, alkaline etching and brightening; (2) The pretreated aluminum alloy parts obtained in step (1) are first immersed in zinc, then dezincified, cleaned and then immersed in zinc a second time. (3) The aluminum alloy parts obtained in step (2) are subjected to alkaline pre-plating of nickel, followed by chemical nickel plating; (4) Degreasing and activation pretreatment are performed on the nickel-plated aluminum alloy parts obtained in step (3); (5) Electroform nickel onto the aluminum alloy parts obtained in step (4).

2. The method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts according to claim 1, characterized in that: In step (1), the degreasing solution for ultrasonic degreasing includes 30~50g / L HS-58 cleaning agent and the remainder water. The ultrasonic degreasing process is ultrasonic degreasing at 15~40℃ for 10-30min.

3. The method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts according to claim 1, characterized in that: In step (1), the alkaline etching solution of the alkaline etching process includes 20~30g / L sodium carbonate, 10~20g / L sodium hydroxide, 20~30g / L sodium phosphate and the balance water. The alkaline etching process is to etch at 50~70℃ for 1-3 minutes. The light extraction solution for the light extraction process includes 30-50 g / L micro-etching salt, 10-20 ml / L sulfuric acid, and the remainder water. The light extraction process is performed at room temperature for 3-10 minutes.

4. The method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts according to claim 1, characterized in that: In step (2), the zinc immersion solution includes sodium hydroxide with a mass fraction of 5-15%, sodium cyanide with a mass fraction of 0-0.5%, nickel sulfate with a mass fraction of 1-5%, and the balance water; the zinc stripping solution includes 30-50 g / L micro-etching salt and the balance water; the first zinc immersion time is 30-60 s, and the second zinc immersion time is 20-40 s.

5. The method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts according to claim 1, characterized in that: In step (3), the alkaline pre-plating nickel solution includes 20-25 g / L nickel sulfate, 20-25 g / L sodium hypophosphite, 25-35 g / L sodium lactate, 10-20 ml / L triethanolamine, 20-30 g / L ammonia and the balance water. The pH of the alkaline pre-plating nickel solution is adjusted with dilute sulfuric acid or ammonia, with a pH range of 9.5-10.

5. The solution temperature is 20-35℃, and the pre-plating time is 3-5 min.

6. The method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts according to claim 1, characterized in that: In step (3), the acidic electroless nickel plating solution includes 20-30 g / L nickel sulfate, 20-30 g / L sodium hypophosphite, 25-35 ml / L lactic acid, 2-3 ml / L propionic acid and the balance water. The pH value of the acidic electroless nickel plating solution is in the range of 4.6-4.8, the temperature is 88-92℃, and the electroless nickel plating time is 0-90 min.

7. The method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts according to claim 1, characterized in that: In step (4), the degreasing agent is HS-58 with a concentration of 30-50 g / L, the degreasing agent temperature is 15-40℃, and the degreasing time is 10-30 min; the activation solution includes 60-100 g / L micro-etching salt, 10-20 ml / L sulfuric acid and the remainder water, the activation temperature is room temperature, and the activation time is 3-5 min.

8. The method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts according to claim 1, characterized in that: In step (5), the electroforming solution comprises 250-400 g / L nickel sulfamate, 20-45 g / L boric acid, 15-25 g / L nickel chloride, and the remainder water. The pH of the electroforming solution is adjusted to 4-4.5 using sulfamate. The electroforming temperature is 28-32℃, and the electroforming current density is 0.5-1.5 A / dm³. 2 The coating thickness is 20~200 μm. During the electroforming process, the cathode rotates at a speed of 3~20 r / min or the surface of the aluminum alloy parts is flushed by a circulating liquid flow.

9. The method for high-quality, complete electroforming of nickel on the surface of aluminum alloy parts according to claim 1, characterized in that: In step (5), the electrical connection point of the electroformed nickel is a threaded hole or a through hole, and the tooling material for the electroformed nickel includes at least one of aluminum alloy, stainless steel, copper alloy or titanium alloy.

10. An aluminum alloy component, characterized in that: Electroforming nickel according to any one of claims 1 to 9.

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