Electroplating process of high-voltage resonant rod

Abstract

The invention relates to the field of tuning part electroplating processing, and discloses an electroplating process of a high-voltage tuning resonance rod, which comprises the following steps: S1, pretreatment of the resonance rod; s2, performing soaking treatment on the pretreated resonance rod by using a first treatment agent to obtain a primarily treated resonance rod; s3, pre-copper-plating treatment of the primary treatment resonance rod; s4, the resonance rod subjected to copper pre-plating is soaked with a second treating agent, and a pretreated resonance rod is obtained; s5, silver plating treatment, water washing and drying are conducted on the pretreated resonance rod, and the high-voltage-modulation resonance rod is obtained; the first treatment agent is prepared from sodium lignin sulfonate, hydroxypropyl trimethyl ammonium chloride chitosan and water, and the second treatment agent is prepared from sodium 2-acrylamido-2-methylpropanesulfonate, 4-ethyl-3-thiosemicarbazide, acetylchitosamine, polyethylene glycol and water. The plating layer of the high-voltage resonance adjusting rod has the advantages of being fine and firm, is not prone to being influenced by high-voltage corona under the condition of bearing radio frequency high voltage for a long time, and is good in reliability.

Description

Technical Field

[0001] This application relates to the field of electroplating of tuning components, and in particular to an electroplating process for a high-voltage tuning resonator. Background Technology

[0002] A high-voltage tuning resonator rod is a tuning element used in high-voltage, high-frequency circuits, commonly found in radio frequency (RF) power amplifiers, broadcast transmitters, particle accelerators, and industrial heating equipment. Its core function is to adjust the resonant frequency mechanically or electronically, enabling the circuit to operate stably within the target frequency band under high-voltage conditions.

[0003] High-voltage resonant tuning pins are typically made of copper or aluminum, and are mostly cylindrical with a boss structure. To improve the ability of high-voltage resonant tuning pins to withstand high radio frequency voltages, they are usually electroplated with silver to reduce corona loss and improve reliability.

[0004] Existing electroplating processes for high-voltage resonant modulators generally include pretreatment, copper pre-plating, silver plating, and post-treatment steps. These processes can form a stable plating structure on the surface of the high-voltage resonant modulator. However, high-voltage resonant modulators need to withstand high radio frequency voltages for extended periods. During long-term use, the micropores in the plating layer become concentration points of the high-voltage electric field, reducing the reliability of the high-voltage resonant modulator during prolonged corona discharge. Summary of the Invention

[0005] To address the issue that existing electroplating processes for high-voltage resonant rods cause micropores in the plating layer to become concentration points of the high-voltage electric field under long-term exposure to radio frequency high voltage, thus reducing the reliability of the high-voltage resonant rod during long-term corona discharge, this application provides an electroplating process for high-voltage resonant rods.

[0006] This application provides an electroplating process for a high-voltage resonant tuning rod, employing the following technical solution: An electroplating process for a high-voltage resonant tuning rod includes the following steps: S1. Pre-process the resonant rod; S2. The pre-treated resonant rod is immersed in the first treatment agent to obtain the pre-treated resonant rod. S3. Pre-plat copper onto the initial processing resonant rod; S4. The pre-plated copper resonant rod is immersed in a second treatment agent to obtain a pre-treated resonant rod. S5. The pre-treated resonant rod is silver-plated, washed with water, and dried to obtain the high-voltage tuned resonant rod. The first treatment agent is prepared from sodium lignosulfonate, hydroxypropyltrimethylammonium chloride chitosan and water, and the second treatment agent is prepared from sodium 2-acrylamido-2-methylpropanesulfonate, 4-ethyl-3-thioaminourea, acetyl glucosamine, polyethylene glycol and water.

[0007] By adopting the above technical solution, step S1 pre-treats the resonant rod to remove oil, impurities, etc. from its surface, making the surface clean and improving the efficiency of subsequent processing. Step S2 uses a first treatment agent made of sodium lignosulfonate, hydroxypropyltrimethylammonium chloride, chitosan, and water to immerse the pre-treated resonant rod, forming a uniform hydrophilic film on its surface and improving the adhesion stability of the plating layer during subsequent copper plating. Step S3 pre-plats the pre-treated resonant rod with copper, which enhances the bonding force between the resonant rod and the subsequent silver plating layer and improves its corrosion resistance to a certain extent. Step S4 uses a second treatment agent made of sodium 2-acrylamido-2-methylpropanesulfonate, 4-ethyl-3-thioaminourea, acetylglucosamine, polyethylene glycol, and water to immerse the pre-copper-plated resonant rod, which has a good synergistic effect and further optimizes the surface condition of the pre-plated copper layer, making the subsequent silver plating layer more uniform and dense. Step S5 involves silver plating the pre-treated resonant rod. The silver plating reduces corona loss in the high-voltage resonant rod and forms a uniform and dense protective coating on its surface. After washing and drying, the high-voltage resonant rod is obtained. This electroplating process gives the high-voltage resonant rod a fine and robust coating, making it less susceptible to corona damage under long-term exposure to high-frequency radio voltage, thus improving its reliability.

[0008] Preferably, the first treatment agent is prepared from the following raw materials by weight percentage: Sodium lignosulfonate 2-4% Hydroxypropyltrimethylammonium chloride chitosan 0.5-1.5% Remaining water.

[0009] By adopting the above technical solution, sodium lignosulfonate can improve the surface condition of the resonant rod and produce a good synergistic effect with hydroxypropyltrimethylammonium chloride chitosan. It can form a uniform protective film on the surface of the resonant rod, which has good film-forming and adsorption properties. This helps to improve the stability, uniformity and density of the pre-plated copper layer, making the pre-plated copper layer finer and stronger, thereby improving the reliability of the high-voltage resonant rod when it is subjected to radio frequency high voltage for a long time.

[0010] Preferably, the second treatment agent is prepared from the following raw materials in weight percentages: Sodium 2-acrylamido-2-methylpropanesulfonate 2-4% 4-Ethyl-3-thioaminourea 0.5-1.2% Acetyl glucosamine 0.5-1% Polyethylene glycol 2-4% Remaining water.

[0011] By adopting the above technical solution, sodium 2-acrylamido-2-methylpropanesulfonate has good permeability and wettability, and can be uniformly dispersed on the surface of the pre-plated copper resonator rod; 4-ethyl-3-thioaminourea can play a certain complexing role, which helps the uniform distribution of metal ions; acetyl glucosamine and polyethylene glycol have dispersing and solubilizing effects, and can synergize with sodium 2-acrylamido-2-methylpropanesulfonate, so that when the pre-plated copper resonator rod is immersed, an adsorption layer is formed on the coating surface, thereby inhibiting the disordered deposition of metal ions, promoting a more compact grain arrangement, and ultimately achieving the effect of refining the coating, reducing the microporous structure of the coating, so that the coating of the obtained high-voltage resonator rod is more dense and firm, and is less susceptible to the influence of high-voltage corona under long-term exposure to radio frequency high voltage, thus having better reliability.

[0012] Preferably, the soaking temperature in step S2 is 40-50℃ and the soaking time is 20-40 minutes.

[0013] By adopting the above technical solution, the resonant rod is immersed in the first treatment agent at a better temperature and time, so that the copper plating layer can be more uniform and firmly attached to the resonant rod during the subsequent pre-plating copper treatment, providing a good foundation for the subsequent silver plating treatment, and helping to improve the fineness and firmness of the plating layer of the high voltage resonant rod.

[0014] Preferably, the soaking temperature in step S4 is 60-70℃ and the soaking time is 15-30 minutes.

[0015] By adopting the above technical solution, the second treatment agent is used to immerse the pre-plated copper resonant rod at a better temperature and time, which allows the second treatment agent to play its full role, optimizes the surface condition of the resonant rod, makes the silver plating layer more dense and firm, and is less susceptible to the influence of high voltage corona when subjected to high radio frequency voltage for a long time, thus improving the reliability of the high voltage tuning resonant rod.

[0016] Preferably, the pretreatment in step S1 includes degreasing, water washing, alkaline etching, and water washing processes.

[0017] By adopting the above technical solution, the pretreatment process of degreasing, water washing, alkaline etching, and water washing on the resonant rod can effectively remove oil, impurities, and oxide layers from the surface of the resonant rod, making the surface of the resonant rod clean and activated. At the same time, it homogenizes the surface structure of the resonant rod, which helps to improve the bonding force between the coating and the surface of the resonant rod, thereby improving the quality and reliability of the coating of the high-voltage resonant rod.

[0018] Preferably, the copper pre-plating temperature in step S3 is 45-55℃, the pre-plating time is 20-30s, and the pre-plating current is 1.5-3A / dm². 2 .

[0019] By adopting the above technical solutions, the better pre-plating copper conditions can make the pre-plated copper layer more uniform, dense, and have better adhesion.

[0020] Preferably, the thickness of the pre-plated copper in step S3 is 1-3 μm.

[0021] By adopting the above technical solution, the optimal thickness of the pre-plated copper can not only provide a good foundation for subsequent silver plating, making the plating layer more firmly bonded and providing better protection, but also avoid material waste and increased costs caused by an excessively thick pre-plated copper layer.

[0022] Preferably, in step S5, the silver plating temperature is 25-35℃, the silver plating time is 10-20s, and the silver plating current is 1.5-3A / dm. 2 .

[0023] By adopting the above technical solution and the superior silver plating conditions, a fine and firm plating layer can be formed on the surface of the high-voltage resonant rod, thereby improving the adhesion stability of the silver plating layer.

[0024] Preferably, the thickness of the silver plating in step S5 is 0.5-1.5 μm.

[0025] By adopting the above technical solution, the silver plating layer with a better thickness can uniformly fill the micropores of the pre-plated copper layer, forming a uniform and dense protective layer on the surface of the pre-plated copper layer, further improving the corona resistance stability of the high-voltage resonant rod.

[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. By sequentially performing pretreatment, immersion in a first treatment agent, copper pre-plating, immersion in a second treatment agent, silver plating, water washing, and drying on the resonant rod, this electroplating process gives the plating layer of the high-voltage resonant rod the advantages of being dense and firm. Under long-term exposure to high-frequency radio voltage, it is not easily affected by high-voltage corona, thus improving the reliability of the high-voltage resonant rod.

[0027] 2. Immersing the pre-treated resonant rod with a first treatment agent made from sodium lignosulfonate, hydroxypropyltrimethylammonium chloride, chitosan, and water can form a uniform protective film on the surface of the resonant rod. This film has good film-forming and adsorption properties, which helps to improve the bonding stability, uniformity, and density of the pre-plated copper layer.

[0028] 3. The copper-plated resonant rod is immersed in a second treatment agent prepared from sodium 2-acrylamido-2-methylpropanesulfonate, 4-ethyl-3-thioaminourea, acetylglucosamine, polyethylene glycol and water. This immersion treatment forms an adsorption layer on the plating surface, thereby inhibiting the disordered deposition of metal ions, promoting a tighter grain arrangement, and ultimately refining the plating layer. This reduces the micropore structure of the plating layer and helps to make the plating layer of the high-voltage resonant rod finer and stronger. Attached Figure Description

[0029] Figure 1 This is a physical image of the high-voltage resonant tuning rod of this application. Detailed Implementation

[0030] The following is in conjunction with the appendix Figure 1 The present application will be further described in detail with reference to the embodiments.

[0031] The following are some of the sources and specifications of the raw materials used in this application. The raw materials used in the preparation examples and embodiments of this application can all be obtained commercially, including but not limited to the following models and manufacturers of raw materials. Raw materials with equivalent performance can also be used: 1. Sodium lignosulfonate: CAS No. 8061-51-6, content 99%; 2. Hydroxypropyltrimethylammonium chloride chitosan: Kemic, degree of substitution greater than 90%; 3. Sodium 2-acrylamido-2-methylpropanesulfonate: CAS No. 5165-97-9, content 50%; 4. 4-Ethyl-3-thioaminourea: CAS No. 13431-34-0, content 98%; 5. Acetyl glucosamine: CAS No. 7512-17-6, content 99%; 6. Polyethylene glycol: Polyethylene glycol 400, Polyethylene glycol 800 or Polyethylene glycol 1000. Example

[0032] Example 1 Example 1 discloses an electroplating process for a high-voltage resonant tuning rod, comprising the following steps: S1. Pre-treatment of aluminum resonant rod: First, use degreasing agent to clean the resonant rod, controlling the degreasing temperature at 50℃ and the degreasing time at 5min. Then, perform 1-2 water washes. After water washes, use alkaline etchant for alkaline etching, controlling the alkaline etching temperature at 50℃ and the alkaline etching time at 30s. Then, perform 1-2 water washes. After water washes, use zinc immersion agent for zinc immersion, controlling the zinc immersion temperature at 25℃ and the zinc immersion time at 30s. Then, perform 1-2 water washes. S2. The pre-treated resonant rod is immersed in the first treatment agent, which is made of 0.2 kg sodium lignosulfonate, 0.15 kg hydroxypropyltrimethylammonium chloride chitosan and 9.65 kg water. The immersion temperature is controlled at 40℃ and the immersion time is 40 min to obtain the pre-treated resonant rod. S3. Pre-plat the initial-treated resonant rod with copper plating agent, controlling the pre-plating temperature at 45℃, the pre-plating time at 30s, and the pre-plating current at 1.5A / dm. 2 The thickness of the pre-plated copper is 1μm; S4. The pre-plated copper resonant rod is immersed in a second treatment agent, which consists of 0.2 kg of sodium 2-acrylamido-2-methylpropanesulfonate, 0.05 kg of 4-ethyl-3-thioaminourea, 0.1 kg of acetylglucosamine, 0.2 kg of polyethylene glycol 800 and 9.45 kg of water. The immersion temperature is controlled at 60°C and the immersion time is 30 min to obtain the pre-treated resonant rod. S5. Apply silver plating agent to the pretreated resonant rod, controlling the plating temperature at 25℃, the plating time at 20s, and the plating current at 3A / dm. 2 The silver plating thickness is 1.5μm. After washing and drying, a high-voltage resonant tuning rod is obtained. The structure of the high-voltage resonant tuning rod is as follows: Figure 1 As shown; The degreasing agent is a commercially available acidic degreasing agent, with no limit on the type, and the usage ratio is 10wt%. The alkaline etchant used was Henkel BONDERITE C-AK 305 from Germany, at a concentration of 5 wt%. The zinc precipitation agent is Bigley BC-22, used at a ratio of 25 wt%. The copper plating agent used for pre-plating is Yishun Chemical Q / YS.138, with a concentration of 20wt%. The silver plating agent used is Yishun Chemical Q / YS.811, with a concentration of 20wt%.

[0033] Example 2-3 The difference between Examples 2-3 and Example 1 lies in the amount of raw materials used and the preparation process parameters, as detailed in Table 1 below.

[0034] Table 1 Parameter table for Examples 1-3 Comparative Example Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that in the first treatment agent, hydroxypropyltrimethylammonium chloride chitosan was replaced with an equal amount of chitosan, while the rest was the same as in Example 1.

[0035] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that sodium lignosulfonate was replaced with an equal amount of hydroxypropyltrimethylammonium chloride chitosan in the first treatment agent, while the rest was the same as in Example 1.

[0036] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that in the second treatment agent, 4-ethyl-3-thioaminourea is replaced with an equal amount of thiourea, while the rest is the same as in Example 1.

[0037] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that acetyl glucosamine was replaced with polyethylene glycol 800 in equal amounts, while the rest was the same as in Example 1.

[0038] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that sodium 2-acrylamido-2-methylpropanesulfonate was replaced with an equal amount of 4-ethyl-3-thioaminourea, otherwise it was the same as Example 1.

[0039] Comparative Example 6 The difference between Comparative Example 6 and Example 1 is that step S2 is not performed in the electroplating process, and the resonant rod after pretreatment is directly pre-plated with copper. Otherwise, it is the same as Example 1.

[0040] Comparative Example 7 The difference between Comparative Example 7 and Example 1 is that step S4 is omitted in the electroplating process, and the resonant rod after pre-plating copper is directly plated with silver. Otherwise, it is the same as Example 1.

[0041] Performance testing The performance of the high-voltage resonant tuning rods prepared in Examples 1-3 and Comparative Examples 1-7 is tested below: 1. Coating adhesion test: The coating of the high-voltage resonant rod was tested for 1000 hours at 85℃ and 85% humidity. The coating was vertically peeled off using 3M tape, and the peeling was observed under a microscope. The adhesion level was recorded as follows: no peeling was recorded as level 0, peeling of less than 5% of the area was recorded as level 1, peeling of 5-10% of the area was recorded as level 2, peeling of 10-20% of the area was recorded as level 3, peeling of 20-30% of the area was recorded as level 4, and peeling of more than 30% of the area was recorded as level 5.

[0042] 2. Coating roughness test: The roughness (Ra, μm) of the high-voltage resonant rod was measured using a 3D profile measuring instrument, and the test results were recorded.

[0043] 3. Withstand voltage performance test: Using a voltage breakdown tester, adjust the output voltage to 10kV and test whether the high-voltage resonant rod is broken down. Test and record the test results.

[0044] The following are the performance test data of the high-voltage resonant rods in Examples 1-3 and Comparative Examples 1-7, as detailed in Table 2 below.

[0045] Table 2 Performance data of Examples 1-3 and Comparative Examples 1-7 Based on Examples 1-3 and Comparative Examples 1-2, and referring to Table 2, it can be concluded that treating the resonant rod with the first treatment agent prepared using the specific components of this application results in a high-voltage resonant rod with good adhesion stability and a fine surface. In Comparative Examples 1 and 2, the components of the first treatment agent were changed, leading to a decrease in the adhesion level and an increase in roughness of the resulting high-voltage resonant rod. This may be because the change in the first treatment agent reduced the stability of the pre-plated copper in the pre-plating process, thereby reducing the adhesion stability and density of the plating layer.

[0046] Based on Examples 1-3 and Comparative Examples 3-5, and referring to Table 2, it can be concluded that treating the resonant rod with the second treatment agent containing specific components of this application results in a high-voltage resonant rod with good adhesion stability, good surface density, and resistance to high-voltage breakdown, exhibiting good corona resistance. In Comparative Examples 3-5, the components of the second treatment agent were changed, resulting in a decrease in the adhesion level of the high-voltage resonant rod, a significant increase in roughness, and partial high-voltage breakdown, possibly due to reduced density and adhesion stability of the silver plating layer.

[0047] Combining Examples 1-3 and Comparative Examples 6-7 with Table 2, it can be concluded that the electroplating process of this application, which includes pretreatment, first treatment agent treatment, pre-plating copper, second treatment agent treatment, and silver plating, significantly improves the plating stability, density, and corona resistance of the obtained high-voltage resonant rod under the synergistic effect of the initial treatment and pretreatment processes. In Comparative Example 6, the first treatment agent treatment was not performed, and in Comparative Example 7, the second treatment agent treatment was not performed, resulting in a significant decrease in the properties of the obtained high-voltage resonant rod.

[0048] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A plating process for a high pressure tuning fork, characterized in that, The method comprises the following steps: S1, pretreating the resonant rod; S2, soaking the pretreated resonant rod with a first treating agent to obtain a primary treated resonant rod; S3, pre-plating copper on the primary treated resonant rod; S4, soaking the pre-plated resonant rod with a second treating agent to obtain a pretreated resonant rod; S5, plating silver on the pretreated resonant rod, washing with water, drying, and obtaining a high-voltage tuning resonant rod; The first treating agent is prepared from sodium lignosulfonate, hydroxypropyltrimethylammonium chloride chitosan, and water, and the second treating agent is prepared from 2-acrylamido-2-methylpropanesulfonic acid sodium, 4-ethyl-3-thiosemicarbazide, acetylchitosamine, polyethylene glycol, and water.

2. The electroplating process of a high pressure tuning stem according to claim 1, wherein, The first treating agent is prepared from the following raw materials in the following weight percentages: Sodium lignosulfonate 2-4% Hydroxypropyltrimethylammonium chloride chitosan 0.5-1.5% The balance is water.

3. The electroplating process of a high pressure tuning stem according to claim 1, wherein, The second treating agent is prepared from the following raw materials in the following weight percentages: 2-acrylamido-2-methylpropanesulfonic acid sodium 2-4% 4-ethyl-3-thiosemicarbazide 0.5-1.2% Acetylchitosamine 0.5-1% Polyethylene glycol 2-4% The balance is water.

4. The electroplating process of a high pressure tuning stem according to claim 1, wherein, The soaking temperature in the S2 step is 40-50℃, and the soaking time is 20-40 min.

5. The electroplating process of a high pressure tuning stem according to claim 1, wherein, The soaking temperature in the S4 step is 60-70℃, and the soaking time is 15-30 min.

6. The electroplating process of a high pressure tuning stem according to claim 1, wherein, The pretreatment in the S1 step comprises the following procedures: oil removal, water washing, alkali etching, and water washing.

7. The electroplating process of a high pressure tuning stem according to claim 1, wherein, The pre-plating copper temperature in the S3 step is 45-55℃, the pre-plating copper time is 20-30 s, and the pre-plating copper current is 1.5-3 A / dm².

8. The electroplating process of a high pressure tuning stem according to claim 1 or 7, wherein, The pre-plating copper thickness in the S3 step is 1-3 µm.

9. The electroplating process of a high pressure tuning stem according to claim 1, wherein, The plating silver temperature in the S5 step is 25-35℃, the plating silver time is 10-20 s, and the plating silver current is 1.5-3 A / dm².

10. The electroplating process of a high pressure tuning stem according to claim 1, wherein, The plating silver thickness in the S5 step is 0.5-1.5 µm.

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