Etching method for stainless steel radiating fin of switch

Abstract

The invention relates to the technical field of precision metal processing, in particular to an etching method for a stainless steel cooling fin of a switch. The etching method of the stainless steel radiating fin of the switch comprises the following steps: S1, deoiling, cleaning and activating; s2, silk-screen printing of photosensitive ink; s3, the stainless steel substrate treated in the step S2 is put into chemical etching liquid to be subjected to etching treatment; and S4, the etched stainless steel substrate is soaked in a sodium hydroxide solution with the temperature being 80 DEG C and the mass concentration being 5% to remove the surface photosensitive ink, then deionized water is adopted for cleaning, drying treatment is conducted, and the stainless steel cooling fin of the switch is obtained. According to the etching method disclosed by the invention, by accurately controlling the procedures of oil removal cleaning, activation, photosensitive ink screen printing and surface etching, efficient and accurate etching of the stainless steel radiating fin of the switch is realized, so that the width error of the etching groove is less than or equal to 0.005 mm, the edge flatness of the groove is high, and the depth error of the etching groove is less than or equal to 0.01 mm.

Description

Technical Field

[0001] The present application relates to the technical field of precision metal processing, and in particular to an etching method for a stainless steel heat sink of a switch. Background Art

[0002] At present, the surface treatment technology of stainless steel switch heat sinks generally adopts physical and chemical methods, but there are certain limitations in etching accuracy and flatness control, which limits the reliability and service life of the finished product. It is difficult to accurately control the groove spacing, edge flatness and depth consistency during the etching process, especially in the processing of tiny structural parts, which is prone to problems such as poor adhesion and poor corrosion. Although there are methods to improve the above problems by adjusting the composition and temperature of the etching solution, there is a lack of a complete and reusable high-precision etching process, which makes the consistency and reliability of the product not effectively guaranteed. Faced with the trend of miniaturization and high performance of electronic products, it is urgent to develop a new process that can enhance the corrosion resistance and cleanliness of the heat sink surface while ensuring extremely high precision, so as to meet the future market demand for high-quality components. Summary of the invention

[0003] In view of the shortcomings of the prior art, the present application provides an etching method for a stainless steel heat sink for a switch. By precisely controlling the degreasing, cleaning and activation of the stainless steel substrate, silk-screening of photosensitive ink and surface etching processes, a stainless steel heat sink for a switch with high corrosion resistance and excellent heat dissipation performance is obtained. At the same time, the stainless steel heat sink has an extremely high etching groove width error of ≤0.005mm, an extremely high groove edge flatness, and an extremely high etching groove depth error of ≤0.01mm.

[0004] The present application provides a method for etching a stainless steel heat sink of a switch, which adopts the following technical solution: A method for etching a stainless steel heat sink of a switch, comprising the following steps: S1. Degreasing, cleaning and activation: The stainless steel substrate is degreasingly cleaned by high-pressure sputtering spraying degreasing cleaning solution at a cleaning speed of 5.864 m / s, and then deionized water is cleaned by high-pressure sputtering spraying, and activation liquid is again high-pressure sputtering spraying to remove oxide scale, and finally deionized water is cleaned by high-pressure sputtering spraying to obtain a clean stainless steel substrate; S2, screen printing photosensitive ink: After drying the clean surface of the stainless steel substrate, screen print the photosensitive ink according to the pre-designed pattern, and then use 2000W ultraviolet light heat energy 878Jr / s for primary photolysis exposure, and then use 9000W ultraviolet light heat energy 2113Jr / s for secondary photolysis curing after development; the photosensitive ink is the photosensitive ink of Guangdong Sanqiu Photocurable Materials Co., Ltd.; S3, placing the stainless steel substrate processed in step S2 into a chemical etching solution for etching, and when the etching groove width and etching groove depth required are obtained, the etching is stopped, and the surface is washed with deionized water to obtain the etched stainless steel substrate; S4. Soak the etched stainless steel substrate in a 5% sodium hydroxide solution at a temperature of 80° C. to remove the surface photosensitive ink, then wash it with deionized water and dry it to obtain a stainless steel heat sink for the switch.

[0005] By adopting the above technical solution, the etching method of the present application is an efficient and precise etching process for the stainless steel heat sink of the switch, which is achieved through the following four main steps: 1. Degreasing, cleaning and activation: The purpose of this step is to remove the oil and oxide scale on the stainless steel substrate to prepare for the subsequent screen printing photosensitive ink and etching process. By spraying degreasing cleaning solution, deionized water and activation solution with high-pressure sputtering, it can be ensured that the surface of the stainless steel substrate is clean and free of impurities, which is conducive to the subsequent process. 2. Screen printing photosensitive ink: Screen print photosensitive ink on a clean stainless steel substrate, and use ultraviolet light thermal energy for primary photolysis exposure and secondary photolysis curing to form a patterned photosensitive layer. This step is the key to the etching process because it determines the shape and dimensional accuracy of the final heat sink. 3. Chemical etching: The stainless steel substrate with the photosensitive layer is placed in a chemical etching solution for etching until the required etching groove width and depth are reached. During the etching process, adding a chelating agent can reduce the free metal ions in the solution and maintain the stability of the etching solution; inorganic acids such as nitric acid can promote the oxidation of elements such as iron and nickel in stainless steel and accelerate the etching process; and the sulfur element in thiourea peroxide and sodium persulfate helps the precipitation of heavy metal ions, further promoting the etching reaction. 4. Remove the photosensitive ink: After the etching is completed, the etched stainless steel substrate is immersed in a 5% sodium hydroxide solution at 80°C to remove the photosensitive ink on the surface, and then washed with deionized water and dried to obtain the final switch stainless steel heat sink. The entire etching method achieves efficient and accurate etching of the switch stainless steel heat sink by precisely controlling each process, while ensuring the high corrosion resistance and excellent heat dissipation performance of the heat sink.

[0006] Preferably, in step S1, the degreasing cleaning solution is 65-70 g / L sodium hydroxide, and the temperature is 70-90°C; the activation solution is 10-15 g / L ferric chloride, 10-12 g / L hydrochloric acid with a mass concentration of 37%, and the temperature is 35-40°C.

[0007] Preferably, in step S1, the spraying pressure of the high pressure sputtering spray is 2.5 kg / cm 2 .

[0008] Preferably, in step S3, the chemical etching solution comprises the following components: 320-350 g / L of ferric chloride, 80-90 g / L of accelerator, 20-30 g / L of inorganic acid, 10-12 g / L of chelating agent, and 3-4 g / L of stabilizer.

[0009] By adopting the above technical solution, ferric chloride is used as the main etchant. Ferric chloride can oxidize metal elements such as iron and nickel on the stainless steel substrate, thereby dissolving these metals and achieving the etching effect. It works together with the promoter to accelerate the etching reaction. At the same time, the chelating agent helps maintain the balance of metal ions in the solution and stabilize the etching rate. The thiourea peroxide and sodium persulfate in the promoter decompose to release active oxygen, which can further oxidize the stainless steel surface and enhance the etching effect. It is used in conjunction with ferric chloride to improve the etching efficiency. In addition, the sulfur element in the promoter helps to precipitate heavy metal ions in the solution and maintain the cleanliness of the solution. Inorganic acid (nitric acid and hydrochloric acid): Nitric acid can oxidize metal elements such as iron and nickel in stainless steel and promote the etching process. Hydrochloric acid helps to dissolve chromium oxide and accelerate the etching rate of chromium. Inorganic acid works together with ferric chloride and promoters to accelerate the etching process of stainless steel and ensure the stability and efficiency of the etching solution. Chelating agents can form stable complexes with iron ions, nickel ions and chromium ions generated in the chemical etching solution to reduce the concentration of free metal ions in the solution. Through chelation, the stability of the etching solution is maintained, the accumulation of metal ions is prevented from affecting the etching effect, and the etching reaction is promoted to proceed in the positive direction. The stabilizer is used to maintain the stability of the chemical etching solution and prevent unnecessary changes in the solution during use. Working together with the chelating agent, it ensures the stability and consistency of the solution during the etching process, and ensures the etching accuracy and quality. In summary, the chemical etching solution in step S3 achieves efficient and accurate etching of the stainless steel heat sink of the switch through the synergistic effect of ferric chloride, accelerator, inorganic acid, chelating agent and stabilizer. This combination not only improves the etching efficiency, but also ensures the quality and performance of the product.

[0010] Preferably, the inorganic acid is composed of hydrochloric acid with a mass concentration of 37% and nitric acid with a mass concentration of 50% in a mass ratio of 1:1.

[0011] By adopting the above technical scheme, the inorganic acid is composed of hydrochloric acid with a mass concentration of 37% and nitric acid with a mass concentration of 50% in a mass ratio of 1:1. This combination plays a key role in the etching process, which is specifically manifested in the following aspects: Promoting the etching of stainless steel: hydrochloric acid and nitric acid are both strong acids, which can react chemically with metal elements such as iron and nickel in stainless steel, thereby promoting the etching of stainless steel. Among them, nitric acid has stronger oxidizing properties, which can oxidize elements such as iron and nickel in stainless steel into corresponding oxides, further promoting the etching reaction. Hydrochloric acid and nitric acid have a synergistic effect in the etching process. On the one hand, nitric acid can oxidize elements such as iron and nickel in stainless steel into oxides, providing more reactants for hydrochloric acid; on the other hand, hydrochloric acid can react with oxides generated by nitric acid, accelerating the dissolution of oxides, thereby accelerating the etching speed. In addition, hydrochloric acid can also promote the dissolution of chromium oxide and accelerate the etching of chromium. By adjusting the ratio of hydrochloric acid and nitric acid, precise control of the etching rate can be achieved. Hydrochloric acid and nitric acid are composed in a specific mass ratio, which can not only ensure sufficient etching ability, but also avoid the reduction of precision caused by excessive etching rate. Chelating agents can chelate iron ions, nickel ions and chromium ions generated in chemical etching solutions, reduce free metal ions in the solution, and promote the etching reaction to proceed in the positive direction. The combination of hydrochloric acid and nitric acid can maintain the pH value of the etching solution stable to a certain extent, which is conducive to the role of the chelating agent. In summary, the combination of inorganic acids (hydrochloric acid and nitric acid) used in this application plays an important role in the etching process of the stainless steel heat sink of the switch. They not only promote the etching of stainless steel, but also improve the etching efficiency and accuracy through synergistic effects, while helping to maintain the stability of the etching solution.

[0012] Preferably, the accelerator consists of thiourea peroxide and sodium persulfate in a mass ratio of 2:1.

[0013] By adopting the above technical solution, thiourea peroxide and sodium persulfate are used as promoters to accelerate the etching speed of the chemical etching solution on the stainless steel substrate. Under acidic conditions, thiourea peroxide decomposes to produce active oxygen atoms, which react chemically with the surface of stainless steel to accelerate the etching process; while sodium persulfate can provide additional oxidizing capacity to further enhance the etching effect. The active oxygen atoms produced by the decomposition of thiourea peroxide can oxidize heavy metal ions such as iron ions and nickel ions produced during the etching process into corresponding high-valent states, and then form precipitates with other components in the solution. The formation of this precipitate helps to reduce the concentration of free metal ions in the solution and promote the forward etching reaction. After adding the chelating agent, the synergistic effect between thiourea peroxide and sodium persulfate is more obvious. The chelating agent can form a stable complex with iron ions, nickel ions, etc. in the solution, thereby reducing the activity of these metal ions and slowing down their influence on the stability of the etching solution. At the same time, the chelating agent can also increase the pH value of the etching solution, which is conducive to the role of thiourea peroxide and sodium persulfate under acidic conditions. Since thiourea peroxide and sodium persulfate have high etching ability and good selectivity, they can achieve extremely high groove edge flatness and extremely low etching groove depth error (≤0.01mm) while ensuring that the etching groove width error is ≤0.005mm. This is a very important performance indicator for the stainless steel heat sink of the switch.

[0014] Preferably, the chelating agent is composed of diethylenetriaminepentaacetic acid, potassium sodium tartrate and trisodium methylamino acid diacetate in a mass ratio of 3:3:2.

[0015] By adopting the above technical solution, the chelating agent is composed of diethylenetriaminepentaacetic acid (DTPA), potassium sodium tartrate and trisodium methylamino acid diacetate in a mass ratio of 3:3:2. There is a synergistic effect between these components, which jointly improves the stability and etching efficiency of the etching solution. Diethylenetriaminepentaacetic acid (DTPA): DTPA is a powerful chelating agent that can form stable complexes with a variety of metal ions. During the etching process, DTPA can effectively chelate iron ions, nickel ions and chromium ions in the solution, reduce the free state of these metal ions, and thus reduce their interference with the etching reaction. In addition, DTPA can also improve the pH stability of the etching solution and help maintain the consistency of the etching rate. Potassium sodium tartrate is a commonly used buffer and chelating agent that can form a soluble complex with metal ions to help maintain the acid-base balance of the etching solution. During the etching process, potassium sodium tartrate can neutralize the generated hydrogen ions to prevent the solution from being overly acidic or overly alkaline, thereby maintaining the stability of the etching solution. Trisodium methylamino acid diacetate: This compound is also an effective chelating agent that can form a stable complex with metal ions. Its effect is similar to DTPA, which can help chelate metal ions in the solution and reduce their free state, thereby reducing interference with the etching reaction. The combined use of these three chelating agents can achieve the following synergistic effects: Enhanced chelation: Different chelating agents have different affinities for different metal ions. The combined use can improve the overall chelation effect and more effectively control the concentration of metal ions in the solution. Improve the stability of the etching solution: Through buffering and pH adjustment, the pH of the etching solution is kept stable, which is conducive to the etching reaction. Promote etching reaction: Chelating agents can reduce the interference of metal ions, make the etching reaction smoother, and improve etching efficiency and accuracy. In summary, the combination of diethylenetriaminepentaacetic acid, potassium sodium tartrate and trisodium methylamino acid diacetate as a chelating agent plays an important role in the etching process of the switch stainless steel heat sink. Through their synergistic effect, efficient and accurate etching effects are achieved.

[0016] Preferably, the stabilizer is 1,1,3,3-tetramethyldisiloxane.

[0017] Preferably, in step S3, the temperature of the chemical etching solution is 40-50°C.

[0018] Preferably, the temperature of the chemical etching solution is 48°C.

[0019] By adopting the above technical solution, at a temperature of 48°C, the active ingredients in the chemical etching solution (such as ferric chloride, inorganic acid, etc.) are more active and can react chemically with the stainless steel substrate more quickly, thereby accelerating the etching process. The appropriate temperature helps to control the viscosity and fluidity of the etching solution, so that the etching solution can cover the surface of the stainless steel substrate more evenly, reduce local over-etching or under-etching, and thus improve the accuracy of the etching groove width and depth. At a temperature of 48°C, the chelating effect of the chelating agent on iron ions, nickel ions and chromium ions is enhanced, more effectively reducing the free metal ions in the solution, maintaining the stability of the etching solution and the consistency of the etching rate. The increase in temperature makes the active ingredients in the accelerator (such as thiourea peroxide and sodium persulfate) more active, and the separated sulfur element is more likely to react with the heavy metal ions in the solution after etching to form a precipitate, thereby further promoting the etching reaction. At a temperature of 48°C, the oxidation effect of inorganic acids (such as nitric acid and hydrochloric acid) on elements such as iron and nickel in stainless steel and the dissolution effect of chromium oxide are enhanced, which speeds up the etching rate of these elements and avoids the dense oxide layer that chromium easily forms at room temperature from hindering the etching process. In summary, setting the temperature of the chemical etching solution to 48°C in this application has multiple effects of promoting the reaction rate, optimizing the etching effect, enhancing the role of chelating agents and promoters, and exerting the synergistic effect of inorganic acids, thereby achieving efficient and accurate etching of the stainless steel heat sink of the switch.

[0020] In summary, the present application includes at least one of the following beneficial technical effects: 1. Improved etching accuracy and surface quality: By precisely controlling the degreasing, activation, screen printing photosensitive ink and surface etching processes, efficient and accurate etching of the switch stainless steel heat sink is achieved, making the etching groove width error ≤0.005mm, the groove edge flatness is high, and the etching groove depth error ≤0.01mm.

[0021] 2. Enhanced heat dissipation performance: The special chemical etching solution formula, including ferric chloride, accelerator, inorganic acid, chelating agent and stabilizer, can effectively remove the oxide scale on the surface of the stainless steel substrate and improve the heat dissipation performance.

[0022] 3. Improved corrosion resistance: By adding chelating agents, the iron ions, nickel ions and chromium ions generated in the chemical etching solution can be chelated, reducing the free metal ions in the solution, promoting the positive etching reaction, and maintaining a stable etching rate of the etching solution. At the same time, the hydrochloric acid in the inorganic acid can promote the dissolution of chromium oxide and accelerate the etching of chromium, thereby improving the corrosion resistance of the heat sink surface.

[0023] 4. Improved cleanliness: During the etching process, using deionized water to clean the surface can effectively remove residual chemicals and improve the cleanliness of the heat sink surface.

[0024] 5. Simplified production process: The etching method of the present application is simple and easy to implement, and can be completed through only four steps: degreasing and cleaning, activation, silk-screen printing of photosensitive ink and surface etching, which greatly simplifies the production process and reduces production costs.

[0025] Figure Description In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following is a brief introduction to the drawings used in the embodiments: Figure 1 This is a physical picture of the stainless steel substrate to be degreased in Example 3; Figure 2 This is a physical picture of the stainless steel heat sink prepared in Example 3. DETAILED DESCRIPTION

[0026] The embodiments of the present application will be described in detail below in conjunction with the examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. In the examples, if specific conditions are not specified, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0027] Example 1 A method for etching a stainless steel heat sink of a switch, comprising the following steps: S1. Degreasing, cleaning and activation: The stainless steel substrate is degreasing and cleaned by high-pressure sputtering spraying degreasing cleaning solution at a cleaning speed of 5.864 m / s, and then deionized water is cleaned by high-pressure sputtering spraying, and the activation solution is again sprayed by high-pressure sputtering spraying to remove the oxide scale, and finally deionized water is cleaned by high-pressure sputtering spraying to obtain a clean stainless steel substrate; wherein the degreasing cleaning solution is 65 g / L sodium hydroxide at a temperature of 70°C; the activation solution is 15 g / L ferric chloride and 12 g / L hydrochloric acid with a mass concentration of 37% at a temperature of 40°C; the spraying pressure of the high-pressure sputtering spraying is 2.5 kg / cm 2 ; S2, screen printing photosensitive ink: after drying the clean surface of the stainless steel substrate, screen print the photosensitive ink according to the pre-designed pattern, and then use 2000W ultraviolet heat energy 878Jr / s for primary photolysis exposure, and then use 9000W ultraviolet heat energy 2113Jr / s for secondary photolysis curing after development; the photosensitive ink is the photosensitive ink of Guangdong Sanqiu Photocuring Materials Co., Ltd.; S3, put the stainless steel substrate treated in step S2 into a chemical etching solution at a temperature of 40°C for etching treatment, and stop etching when the required etching groove width and etching groove depth are obtained, and use deionized water to clean the stainless steel substrate. The surface is washed to obtain an etched stainless steel substrate; wherein the chemical etching solution comprises the following components: 350 g / L ferric chloride, 90 g / L accelerator, 30 g / L inorganic acid, 12 g / L chelating agent, and 4 g / L 1,1,3,3-tetramethyldisiloxane; the inorganic acid is composed of hydrochloric acid with a mass concentration of 37% and nitric acid with a mass concentration of 50% in a mass ratio of 1:1, the accelerator is composed of thiourea peroxide and sodium persulfate in a mass ratio of 2:1, and the chelating agent is composed of diethylenetriaminepentaacetic acid, potassium sodium tartrate and trisodium methylamino acid diacetate in a mass ratio of 3:3:2; S4. Soak the etched stainless steel substrate in a 5% sodium hydroxide solution at a temperature of 80° C. to remove the surface photosensitive ink, then wash it with deionized water and dry it to obtain a stainless steel heat sink for the switch.

[0028] Example 2 A method for etching a stainless steel heat sink of a switch, comprising the following steps: S1. Degreasing, cleaning and activation: The stainless steel substrate is degreasing and cleaned by high-pressure sputtering spraying degreasing cleaning solution at a cleaning speed of 5.864 m / s, and then deionized water is cleaned by high-pressure sputtering spraying, and the activation solution is again sprayed by high-pressure sputtering spraying to remove the oxide scale, and finally deionized water is cleaned by high-pressure sputtering spraying to obtain a clean stainless steel substrate; wherein the degreasing cleaning solution is 70 g / L sodium hydroxide at a temperature of 90°C; the activation solution is 10 g / L ferric chloride and 10 g / L hydrochloric acid with a mass concentration of 37% at a temperature of 35°C; the spraying pressure of the high-pressure sputtering spraying is 2.5 kg / cm 2 ; S2, screen printing photosensitive ink: after drying the clean surface of the stainless steel substrate, screen print the photosensitive ink according to the pre-designed pattern, then use 2000W ultraviolet heat energy 878Jr / s for primary photolysis exposure, and then use 9000W ultraviolet heat energy 2113Jr / s for secondary photolysis curing after development; the photosensitive ink is the photosensitive ink of Guangdong Sanqiu Photocuring Materials Co., Ltd.; S3, put the stainless steel substrate treated in step S2 into a chemical etching solution with a temperature of 50°C for etching treatment, stop etching when the required etching groove width and etching groove depth are obtained, and use deionized water to clean the stainless steel substrate. The surface is washed to obtain an etched stainless steel substrate; wherein the chemical etching solution comprises the following components: 320 g / L ferric chloride, 80 g / L accelerator, 20 g / L inorganic acid, 10 g / L chelating agent, and 3 g / L 1,1,3,3-tetramethyldisiloxane; the inorganic acid is composed of hydrochloric acid with a mass concentration of 37% and nitric acid with a mass concentration of 50% in a mass ratio of 1:1, the accelerator is composed of thiourea peroxide and sodium persulfate in a mass ratio of 2:1, and the chelating agent is composed of diethylenetriaminepentaacetic acid, potassium sodium tartrate and trisodium methylamino acid diacetate in a mass ratio of 3:3:2; S4. Soak the etched stainless steel substrate in a 5% sodium hydroxide solution at a temperature of 80° C. to remove the surface photosensitive ink, then wash it with deionized water and dry it to obtain a stainless steel heat sink for the switch.

[0029] Example 3 A method for etching a stainless steel heat sink of a switch, comprising the following steps: S1. Degreasing, cleaning and activation: The stainless steel substrate is degreasing and cleaned by high-pressure sputtering spraying degreasing cleaning solution at a cleaning speed of 5.864 m / s, and then deionized water is cleaned by high-pressure sputtering spraying, and the activation solution is again sprayed by high-pressure sputtering spraying to remove the oxide scale, and finally deionized water is cleaned by high-pressure sputtering spraying to obtain a clean stainless steel substrate; wherein the degreasing cleaning solution is 68 g / L sodium hydroxide, and the temperature is 80°C; the activation solution is 13 g / L ferric chloride and 11 g / L hydrochloric acid with a mass concentration of 37%, and the temperature is 38°C; the spraying pressure of the high-pressure sputtering spraying is 2.5 kg / cm 2 ; S2, screen printing photosensitive ink: after drying the clean surface of the stainless steel substrate, screen print the photosensitive ink according to the pre-designed pattern, then use 2000W ultraviolet heat energy 878Jr / s for primary photolysis exposure, and then use 9000W ultraviolet heat energy 2113Jr / s for secondary photolysis curing after development; the photosensitive ink is the photosensitive ink of Guangdong Sanqiu Photocuring Materials Co., Ltd.; S3, put the stainless steel substrate treated in step S2 into a chemical etching solution with a temperature of 48°C for etching treatment, stop etching when the required etching groove width and etching groove depth are obtained, and use deionized water for cleaning The surface is etched to obtain a stainless steel substrate; wherein the chemical etching solution comprises the following components: 340 g / L ferric chloride, 85 g / L accelerator, 25 g / L inorganic acid, 11 g / L chelating agent, and 3.5 g / L 1,1,3,3-tetramethyldisiloxane; the inorganic acid is composed of hydrochloric acid with a mass concentration of 37% and nitric acid with a mass concentration of 50% in a mass ratio of 1:1, the accelerator is composed of thiourea peroxide and sodium persulfate in a mass ratio of 2:1, and the chelating agent is composed of diethylenetriaminepentaacetic acid, potassium sodium tartrate and trisodium methylamino acid diacetate in a mass ratio of 3:3:2; S4. Soak the etched stainless steel substrate in a 5% sodium hydroxide solution at a temperature of 80° C. to remove the surface photosensitive ink, then wash it with deionized water and dry it to obtain a stainless steel heat sink for the switch.

[0030] Comparative Example 1 The same as Example 3, except that: in step S3, the inorganic acid is hydrochloric acid with a mass concentration of 37%.

[0031] Comparative Example 2 The same as Example 3, except that: in step S3, the inorganic acid is nitric acid with a mass concentration of 50%.

[0032] Comparative Example 3 The same as Example 3, except that: in step S3, the accelerator is thiourea peroxide.

[0033] Comparative Example 4 The same as Example 3, except that: in step S3, the accelerator is sodium persulfate.

[0034] Comparative Example 5 The same as Example 3, except that: in step S3, the chelating agent is diethylenetriaminepentaacetic acid.

[0035] Comparative Example 6 The same as Example 3, except that: in step S3, the chelating agent is potassium sodium tartrate.

[0036] Comparative Example 7 The same as Example 3, except that: in step S3, the chelating agent is trisodium methylamino acid diacetate.

[0037] Detection test Ten samples of the switch stainless steel heat sinks prepared in Examples 1 to 3 and Comparative Examples 1 to 7 were taken respectively, and the etching groove width and etching groove depth of the stainless steel heat sink were tested using a QV imager of Japan's Mitutoyo model QV-X302P12-C, and the etching groove width error and etching groove depth error were calculated. The test results are shown in Table 1.

[0038] Table 1 Test results project Etching groove width error / mm Etching groove depth error / mm Example 1 0.005 0.01 Example 2 0.004 0.008 Example 3 0.001 0.003 Comparative Example 1 0.009 0.017 Comparative Example 2 0.0013 0.021 Comparative Example 3 0.009 0.019 Comparative Example 4 0.0017 0.0026 Comparative Example 5 0.007 0.014 Comparative Example 6 0.008 0.017 Comparative Example 7 0.009 0.018 Analyzing the data in Table 1, we can see that: 1) The etching method of the switch stainless steel heat sink provided in Examples 1 to 3 obtains a switch stainless steel heat sink with high corrosion resistance and excellent heat dissipation performance by precisely controlling the degreasing, cleaning and activation of the stainless steel substrate, the silk-screen printing of photosensitive ink and the surface etching process. At the same time, the stainless steel heat sink has an extremely high etching groove width error of ≤0.005mm, an extremely high groove edge flatness, and an extremely high etching groove depth error of ≤0.01mm.

[0039] 2) The comparative analysis of the etching accuracy of the switch stainless steel heat sink obtained in combination with Example 3 and Comparative Examples 1-2 shows that the inorganic acid is composed of hydrochloric acid with a mass concentration of 37% and nitric acid with a mass concentration of 50% in a mass ratio of 1:1. The synergistic effect between them can not only ensure sufficient etching ability, but also avoid the reduction of accuracy caused by excessive etching rate. They not only promote the etching of stainless steel, but also improve the etching efficiency and accuracy through synergy, and help maintain the stability of the etching solution.

[0040] 3) The comparative analysis of the etching accuracy of the switch stainless steel heat sink obtained in combination with Example 3 and Comparative Examples 3-4 shows that the accelerator is composed of thiourea peroxide and sodium persulfate in a mass ratio of 2:1. The synergistic effect between them can accelerate the etching speed of the chemical etching solution on the stainless steel substrate. Since thiourea peroxide and sodium persulfate have efficient etching ability and good selectivity, it is possible to achieve extremely high groove edge flatness and extremely low etching groove depth error (≤0.01mm) while ensuring that the etching groove width error is ≤0.005mm.

[0041] 4) A comparative analysis of the etching accuracy of the switch stainless steel heat sink obtained in combination with Example 3 and Comparative Examples 5-7 shows that the chelating agent is composed of diethylenetriaminepentaacetic acid, potassium sodium tartrate and trisodium methylamino acid diacetate in a mass ratio of 3:3:2. There is a synergistic effect between these components, which together improve the stability and etching efficiency of the etching solution. Different chelating agents have different affinities for different metal ions. Their combined use can improve the overall chelating effect and more effectively control the metal ion concentration in the solution. By buffering and pH adjustment, the pH of the etching solution is kept stable, which is conducive to the etching reaction. Promote etching reaction: Chelating agents can reduce the interference of metal ions, make the etching reaction smoother, and improve etching efficiency and accuracy.

[0042] The above embodiments are only used to explain the technical solutions of the present application rather than to limit them. Although the above embodiments provide a specific description of the present application, relevant technical personnel should understand that the specific implementation methods of the present application can still be modified or replaced by equivalents, and any modifications and equivalent replacements that do not depart from the spirit and scope of the present application should be included in the protection scope of the present application.

Claims

1. A method for etching a stainless steel heat sink of a switch, characterized in that: The following steps are involved: S1. Degreasing, cleaning and activation: The stainless steel substrate is degreasingly cleaned by high-pressure sputtering spraying degreasing cleaning solution at a cleaning speed of 5.864 m / s, and then deionized water is cleaned by high-pressure sputtering spraying, and activation liquid is again high-pressure sputtering spraying to remove oxide scale, and finally deionized water is cleaned by high-pressure sputtering spraying to obtain a clean stainless steel substrate; S2, screen printing photosensitive ink: After drying the clean surface of the stainless steel substrate, screen print the photosensitive ink according to the pre-designed pattern, and then use 2000W ultraviolet light heat energy 878Jr / s for the first photolysis exposure, and then use 9000W ultraviolet light heat energy 2113Jr / s for secondary photolysis curing after development; S3, placing the stainless steel substrate processed in step S2 into a chemical etching solution for etching, and when the etching groove width and etching groove depth required are obtained, the etching is stopped, and the surface is washed with deionized water to obtain the etched stainless steel substrate; S4. Soak the etched stainless steel substrate in a 5% sodium hydroxide solution at a temperature of 80° C. to remove the surface photosensitive ink, then wash it with deionized water and dry it to obtain a stainless steel heat sink for the switch.

2. According to the etching method of a switch stainless steel heat sink according to claim 1, it is characterized in that: In step S1, the degreasing cleaning solution is 65-70 g / L of sodium hydroxide, and the temperature is 70-90°C; the activation solution is 10-15 g / L of ferric chloride and 10-12 g / L of hydrochloric acid with a mass concentration of 37%, and the temperature is 35-40°C.

3. According to the etching method of a stainless steel heat sink of a switch according to claim 1, it is characterized in that: In step S1, the spraying pressure of the high-pressure sputtering spraying is 2.5 kg / cm².

4. According to the etching method of a stainless steel heat sink of a switch according to claim 1, it is characterized in that: In step S3, the chemical etching solution includes the following components: 320-350 g / L of ferric chloride, 80-90 g / L of accelerator, 20-30 g / L of inorganic acid, 10-12 g / L of chelating agent, and 3-4 g / L of stabilizer.

5. The etching method of a stainless steel heat sink of a switch according to claim 4, characterized in that: The inorganic acid is composed of hydrochloric acid with a mass concentration of 37% and nitric acid with a mass concentration of 50% in a mass ratio of 1:

1.

6. The etching method of a stainless steel heat sink of a switch according to claim 4, characterized in that: The accelerator is composed of thiourea peroxide and sodium persulfate in a mass ratio of 2:

1.

7. The etching method of a stainless steel heat sink of a switch according to claim 4, characterized in that: The chelating agent is composed of diethylenetriaminepentaacetic acid, potassium sodium tartrate and trisodium methylamino acid diacetate in a mass ratio of 3:3:

2.

8. The etching method for a stainless steel heat sink of a switch according to claim 4, characterized in that: The stabilizer is 1,1,3,3-tetramethyldisiloxane.

9. The etching method of a stainless steel heat sink of a switch according to claim 1, characterized in that: In step S3, the temperature of the chemical etching solution is 40-50°C.

10. The etching method for a stainless steel heat sink of a switch according to claim 9, characterized in that: The temperature of the chemical etching solution is 48°C.

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