A magnesium alloy shell for mouse that is resistant to hand sweat corrosion and a preparation method thereof

Abstract

The present invention belongs to the technical field of magnesium alloy surface corrosion protection, and specifically relates to a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion and a preparation method thereof. The magnesium alloy shell for a mouse that is resistant to hand sweat corrosion, and its preparation method, include the following steps: S1, casting a magnesium alloy as a shell substrate; S2, performing a surface anodizing treatment on the shell substrate, and then performing a nickel plating treatment; S3, coating an anti-fouling coating after the nickel plating treatment. The present invention not only significantly enhances the corrosion resistance of the magnesium alloy by introducing rare earth elements and combining multi-layer surface treatment technology, but also provides multiple protection mechanisms for the shell, greatly improving its durability and ability to resist sweat corrosion. This comprehensive treatment scheme effectively extends the service life of the mouse while ensuring that the shell maintains the advantages of high strength and lightweight, and ensures the smoothness of its appearance and the comfort of the hand, bringing users a more reliable and lasting use experience.

Description

Technical Field

[0001] The invention belongs to the technical field of magnesium alloy surface corrosion protection, and in particular relates to a magnesium alloy shell for a mouse which is resistant to hand sweat corrosion and a preparation method thereof. Background Art

[0002] With the rapid development of modern science and technology, consumers have put forward higher and higher requirements for the lightweight, aesthetics and durability of electronic devices. Magnesium alloy, as a lightweight and high-strength metal material, is widely used in the manufacture of shells for consumer electronic products such as mice due to its low density, high specific strength, good heat dissipation and easy processing and forming. Magnesium alloy shells can not only effectively reduce the overall weight of the product and improve the user's portability, but also show a rich appearance texture through fine processing, satisfying consumers' pursuit of aesthetics.

[0003] However, magnesium alloys also have significant defects in practical applications, namely, their poor corrosion resistance. Especially in application scenarios such as mice that require long-term contact with human sweat, the magnesium alloy shell is easily corroded by salt, moisture and other corrosive substances in sweat, resulting in corrosion spots and oxide layer shedding on the surface, which seriously affects the appearance and structural integrity of the product. This not only reduces the aesthetics of the product, but may also affect the product's performance and lifespan, causing inconvenience to consumers.

[0004] In view of the above technical problems, the present invention proposes a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion and a preparation method thereof, aiming to improve the corrosion resistance of the magnesium alloy shell through innovative material formulation and preparation process, and meet consumers' comprehensive demands for lightweight, aesthetics and durability of electronic products. Summary of the invention

[0005] The purpose of the present invention is to provide a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion and a preparation method thereof, which not only significantly enhances the corrosion resistance of the magnesium alloy, but also provides a multiple protection mechanism for the shell, greatly improving its durability and ability to resist sweat corrosion, effectively extending the service life of the mouse, and ensuring its smooth appearance and comfortable feel.

[0006] A method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion comprises the following steps:

[0007] S1. Casting a magnesium alloy as a shell substrate;

[0008] S2, after the surface of the shell substrate is anodized, nickel-plated;

[0009] S3, after nickel plating, apply antifouling coating to obtain.

[0010] The magnesium alloy, by weight percentage, has the following elemental components: Al: 3%-9%, Zn: 1%-3%, Y: 0.1%-1%, and the balance is Mg.

[0011] Using magnesium alloy with specific composition as the base material of the mouse shell, adding rare earth element Y, and metal elements Zn and Al on the basis of traditional magnesium-aluminum-zinc alloy can improve the corrosion resistance of magnesium alloy and reduce the possibility of chemical reaction with salt and water in hand sweat. This may be because on the one hand, the potential difference between the second phase Mg5Y precipitated by Y and the Mg matrix is ​​small, and the second phase is evenly distributed after casting, forming a more uniform and weaker micro-galvanic corrosion, thereby producing a denser corrosion film, effectively preventing the penetration of harmful anions; on the other hand, by optimizing the content of Zn and Al, combined with the addition of rare earth element Y, the microstructure of magnesium alloy can be improved, the number and size of the second phase can be reduced, and the distribution of the phase can be optimized. Better microstructure means more uniform corrosion behavior and higher corrosion resistance. Reasonable composition design enables a good interaction between magnesium, rare earth elements, zinc and aluminum, thereby synergistically improving the salt resistance and corrosion resistance of magnesium alloy.

[0012] The specific steps of the casting are: weighing magnesium ingots, zinc blocks, aluminum blocks and Mg-30Y master alloys according to the weight percentage of the elements of the magnesium alloy, putting them into an induction melting furnace, heating them to 700-750°C under a protective atmosphere, keeping them warm for 15-25 minutes after they are completely melted, refining, degassing, deslagging and stirring in sequence, standing and keeping them warm for 8-12 minutes, transferring them to a preheated mold for air cooling and forming, and obtaining a shell substrate.

[0013] The specific steps of the surface anodizing treatment are: fixing the shell substrate on the anode, the cathode is a stainless steel plate, immersing the anode and the cathode in the electrolyte, turning on the power supply, and starting the anodizing; after the oxidation is completed, taking out the shell substrate, washing the residual electrolyte on the surface with deionized water, immersing it in hot water for 15 to 25 minutes, and then taking it out and drying it.

[0014] Preferably, the electrolyte is an acidic electrolyte, including any one of oxalic acid solution, sulfuric acid solution, and chromic acid solution.

[0015] Preferably, the voltage of the anodization is 20-50 V, and the oxidation time is 18-22 min.

[0016] The specific steps of the nickel plating treatment are: fixing the shell substrate after surface anodization treatment on the cathode, the anode is a pure nickel plate, immersing the cathode and the anode in the nickel plating solution, turning on the power supply, and starting electroplating; after electroplating, the nickel plating solution remaining on the surface is rinsed with deionized water, and the nickel plating layer is obtained by drying.

[0017] Preferably, the thickness of the nickel plating layer is 5-10 μm.

[0018] Preferably, the formula of the nickel plating solution is: nickel sulfate: 200-300 g / L, nickel chloride: 20-40 g / L, boric acid adjusted pH value to 4.0-4.5, and the operating temperature is 50-60°C.

[0019] The antifouling coating is prepared from raw materials including 15% to 25% fluorocarbon resin, 5% to 15% organic silicon resin, 2% to 4% modified nano silicon dioxide, 1% to 3% polytetrafluoroethylene, and the remainder is supplemented with solvent to 100% by weight.

[0020] In order to further improve the corrosion resistance of magnesium alloy and optimize the feel, the shell surface adopts multi-layer protection treatment. First, a dense oxide film is formed on the surface of magnesium alloy through anodizing process to enhance corrosion resistance and wear resistance; then chemical nickel plating is carried out outside the oxide film to form an efficient barrier layer to further isolate external moisture and salt; finally, an anti-fouling coating is applied. This coating not only has excellent waterproof and oil resistance, but also can effectively reduce the adhesion of hand sweat and facilitate cleaning, preventing corrosion caused by long-term retention of hand sweat. At the same time, the fine-tuned surface treatment process ensures the anti-corrosion effect while maintaining the smooth touch of the shell surface and the comfort of users.

[0021] Preferably, the fluorocarbon resin includes a first fluorocarbon resin and a second fluorocarbon resin.

[0022] Preferably, the mass ratio of the first fluorocarbon resin to the second fluorocarbon resin is 1:(0.5-2); further preferably, it is 1:1.

[0023] Preferably, the first fluorocarbon resin has a solid content of 59% to 61%, a hydroxyl value of 33 to 43 mgKOH / g, a number average molecular weight of 12,000 to 16,000, an acid value of less than 1 mgKOH / g, and a viscosity of 500 to 1,000 cp.

[0024] In some preferred embodiments, the first fluorocarbon resin is purchased from Changxing Chemical Co., Ltd., Taiwan Province, China, 41016S.

[0025] Preferably, the second fluorocarbon resin has a solid content of 49% to 51%, a hydroxyl value of 49 to 59 mgKOH / g, a viscosity of 340 to 500 cp, a fluorine content of 22% to 24%, and a number average molecular weight of 15,000 to 20,000.

[0026] In some preferred embodiments, the second fluorocarbon resin is purchased from Changxing Chemical Co., Ltd., Taiwan Province, China, 4103.

[0027] The use of two specific fluorocarbon resins can improve the anti-corrosion and anti-fouling properties of the coating. This may be due to the synergistic effect of the two resins. On the one hand, the two fluorocarbon resins dissolve in each other and chemically combine in the coating. The fluorine atoms in the coating are connected to the resin molecules through chemical bonds, forming a dense physical barrier that effectively prevents the penetration of foreign substances such as dirt, moisture, and corrosive substances. On the other hand, the low surface energy characteristics of fluorocarbon resins make it difficult for dirt to adhere to the coating surface, further enhancing the anti-fouling effect. In addition, fluorocarbon resin is selected as one of the main resins of the coating, in which the carbon-fluorine bond energy is extremely high and is difficult to be destroyed by corrosive media.

[0028] Preferably, the solid content of the silicone resin is 38% to 42%, and the viscosity is 3500 to 4000 mPa·s.

[0029] In some preferred embodiments, the organic silicone resin is purchased from Qingdao Wanjia Huixin Surface Material Technology Co., Ltd.

[0030] Preferably, the apparent density of the polytetrafluoroethylene is 2.1-2.3 g / cm 3 , tensile strength ≥14MPa, elongation at break ≥140%.

[0031] In some preferred embodiments, the polytetrafluoroethylene is purchased from Daikin of Japan.

[0032] Preferably, the mass ratio of the fluorocarbon resin, the silicone resin and the polytetrafluoroethylene is (8-12):(4-6):1; more preferably, it is 10:5:1.

[0033] The use of fluorocarbon resin, silicone resin and polytetrafluoroethylene as raw materials can further improve the waterproofness, oil resistance and corrosion resistance of the coating. This may be because the surface energy of these three materials is extremely low. When they are used as coating raw materials at the same time, the three materials work synergistically to form a composite interface with extremely low surface energy, making it difficult for water and oil molecules to spread on its surface, thereby improving the waterproof and oil resistance of the coating. At the same time, the molecular chains of fluorocarbon resin and polytetrafluoroethylene have similar chemical properties, which can form good compatibility and interfacial bonding. The introduction of silicone resin can further enhance this compatibility, forming a uniform and dense coating, and improving the corrosion resistance and resistance to wet heat aging of the coating.

[0034] Preferably, the mass ratio of the silicone resin to the modified nano-silicon dioxide is (3-4):1; more preferably, it is 10:3.

[0035] The use of nano-silicon dioxide and silicone resin as raw materials can improve the smoothness of the coating while improving the corrosion resistance of the coating. This may be because on the one hand, the high specific surface area and surface activity of nano-silicon dioxide enable it to effectively fill the tiny pores in the coating, improve the density and hardness of the coating, thereby reducing the roughness of the coating surface, improving the smoothness, and at the same time improving the corrosion resistance of the coating. On the other hand, the hydroxyl groups on the surface of nano-silicon dioxide hydrogen bond with the Si-O bonds in the silicone resin molecules to form a stable physical combination. This combination enhances the mechanical properties and stability of the coating and improves its wear resistance and scratch resistance. However, the particle size of nano-silicon dioxide is too small, the dispersion is poor, and it is easy to agglomerate, which affects other properties of the coating such as smoothness.

[0036] The modified nano-silica preparation method comprises the following steps: dispersing the nano-silica in an ethanol aqueous solution uniformly, adding a silane coupling agent, stirring at 60-70°C for 4-6 hours, filtering, washing with deionized water for 2-3 times, and drying at 100°C to obtain the modified nano-silica.

[0037] Preferably, the nano-silicon dioxide includes a first nano-silicon dioxide, a second nano-silicon dioxide, and a third nano-silicon dioxide.

[0038] Preferably, the mass ratio of the first nano-silicon dioxide, the second nano-silicon dioxide, and the third nano-silicon dioxide is (4-6):(2-4):1; more preferably, it is 5:3:1.

[0039] Preferably, the average particle size of the first nano-silicon dioxide is 10-20 nm, and the specific surface area is 240-260 m 2 / g, the packing density is 0.1~0.15g / cm 3 Further preferably, the average particle size of the first nano-silicon dioxide is 15nm and the specific surface area is 250m 2 / g, the packing density is 0.1~0.15g / cm 3 .

[0040] Preferably, the average particle size of the second nano-silicon dioxide is 25-35 nm, and the specific surface area is 190-210 m 2 / g, the packing density is 0.15~0.18g / cm 3 Further preferably, the average particle size of the second nano-silicon dioxide is 30nm and the specific surface area is 200m 2 / g, the packing density is 0.15~0.18g / cm 3 .

[0041] Preferably, the third nano-silicon dioxide has an average particle size of 60 nm and a specific surface area of ​​150-200 m 2 / g, the packing density is 0.18~0.2g / cm 3 .

[0042] In some preferred embodiments, the nano-silicon dioxide is purchased from Beijing Dekedaojin Technology Co., Ltd.

[0043] Preferably, the volume concentration of ethanol in the ethanol aqueous solution is 60% to 70%.

[0044] Preferably, the solid-to-liquid ratio of the nano-silicon dioxide to the ethanol aqueous solution is 1 g: (20-30) mL.

[0045] Preferably, the silane coupling agent is a mixture of hexamethyldisilazane and γ-mercaptopropyltrimethoxysilane.

[0046] Preferably, the mass ratio of hexamethyldisilazane to γ-mercaptopropyltrimethoxysilane is (4-6):(1-3); more preferably, it is 5:2.

[0047] Preferably, the added amount of the silane coupling agent is 20% to 30% of the mass of the nano-silicon dioxide.

[0048] The use of a specific silane coupling agent to modify three nano-silica particles of different particle sizes can improve the dispersibility of nano-silica, thereby improving the performance of the coating. This may be because on the one hand, nano-silica particles of different particle sizes fill each other to form smaller gaps, making the dispersion of nanoparticles in the resin more uniform, and the active groups on their surface interact strongly with the resin molecular chains to form a stronger interfacial bonding force, thereby enhancing the strength and overall performance of the coating. On the other hand, the silane coupling agent is bonded to the surface of nano-silica and can react with the hydroxyl groups on the surface of nano-silica, significantly reducing the number of hydroxyl groups on its surface, thereby enhancing the hydrophobicity of nano-silica and improving its dispersibility and compatibility in organic solvents. Moreover, some hydroxyl groups on the surface of the modified nano-silica are replaced by methyl groups, which reduces the hydrogen bonding between particles, helps prevent agglomeration, and improves dispersibility. In addition, the silane coupling agent can also combine with the silicone resin to form a three-dimensional cross-linked network, which improves the density and uniformity of the coating, thereby improving the corrosion resistance and stability of the coating.

[0049] Preferably, the solvent is one or more of ethanol and isopropanol; more preferably, it is ethanol.

[0050] The specific steps of applying the antifouling coating are:

[0051] A1. After introducing fluorocarbon resin and silicone resin into the solvent and stirring evenly, add modified nano-silica, continue stirring evenly, add polytetrafluoroethylene, stir evenly, and filter through a 200-400 mesh filter to obtain an antifouling coating;

[0052] A2. Spray the antifouling coating onto the surface of the shell substrate, put it into an oven and cure it.

[0053] Preferably, the antifouling coating has a thickness of 1 to 3 μm.

[0054] Preferably, the specific conditions for the curing are: temperature 120-150° C., and curing time 20-30 min.

[0055] The method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion produces a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion.

[0056] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0057] 1. The present invention provides a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion. By introducing rare earth elements and combining multi-layer surface treatment technology (including anodizing, chemical plating and anti-fouling coating), not only the corrosion resistance of the magnesium alloy is significantly enhanced, but also multiple protection mechanisms are provided for the shell, which greatly improves its durability and ability to resist sweat corrosion, effectively prolongs the service life of the mouse, and ensures its smooth appearance and comfortable feel.

[0058] 2. The present invention uses a magnesium alloy with a specific composition as the base material of the mouse shell. On the basis of the traditional magnesium-aluminum-zinc alloy, rare earth element Y and metal elements Zn and Al are added to improve the corrosion resistance of the magnesium alloy and reduce the possibility of chemical reaction with salt and moisture in hand sweat.

[0059] 3. The present invention selects two specific fluorocarbon resins to improve the corrosion resistance and stain resistance of the coating.

[0060] 4. The present invention uses fluorocarbon resin, silicone resin and polytetrafluoroethylene as raw materials, which can further improve the waterproofness, oil resistance and corrosion resistance of the coating.

[0061] 5. The present invention uses nano silicon dioxide and silicone resin as raw materials, which can improve the smoothness of the coating while improving the corrosion resistance of the coating.

[0062] 6. The present invention uses a specific silane coupling agent to modify three nano-silicon dioxides with different particle sizes, which can improve the dispersibility of the nano-silicon dioxide and thus improve the coating performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art.

[0064] Figure 1This is a photo of the magnesium alloy shell for a mouse that is resistant to hand sweat corrosion as described in Example 1 of the present invention.

[0065] Figure 2 This is a cross-sectional SEM image of the magnesium alloy shell for a mouse that is resistant to hand sweat corrosion as described in Example 1 of the present invention after corrosion.

[0066] Figure 3 This is a cross-sectional SEM image of the magnesium alloy housing for a mouse that is resistant to hand sweat corrosion as described in Example 1 of the present invention before corrosion. DETAILED DESCRIPTION

[0067] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0068] The raw materials described in the present invention are all commercially available, and are specifically as follows:

[0069] The first fluorocarbon resin has a solid content of 59% to 61%, a hydroxyl value of 33 to 43 mgKOH / g, a number average molecular weight of 12,000 to 16,000, an acid value of <1 mgKOH / g, and a viscosity of 500 to 1,000 cp; the second fluorocarbon resin has a solid content of 49% to 51%, a hydroxyl value of 49 to 59 mgKOH / g, a viscosity of 340 to 500 cp, a fluorine content of 22% to 24%, and a number average molecular weight of 15,000 to 20,000; both were purchased from Changxing Chemical Co., Ltd., Taiwan Province, China, 41016S and 4103.

[0070] The solid content of the silicone resin was 38%-42% and the viscosity was 3500-4000 mPa·s, and it was purchased from Qingdao Wanjia Huixin Surface Material Technology Co., Ltd.

[0071] The average particle size of the first nano-silicon dioxide is 15nm and the specific surface area is 250m 2 / g, the packing density is 0.1~0.15g / cm 3 The average particle size of the second nano-silicon dioxide is 30nm and the specific surface area is 200m 2 / g, the packing density is 0.15~0.18g / cm 3 ; The average particle size of the third nano-silicon dioxide is 60nm, and the specific surface area is 150~200m 2 / g, the packing density is 0.18~0.2g / cm 3 ; All purchased from Beijing Dekedaojin Technology Co., Ltd.

[0072] The apparent density of polytetrafluoroethylene is 2.1~2.3g / cm3 , tensile strength ≥14MPa, elongation at break ≥140%, purchased from Daikin, Japan.

[0073] Example 1

[0074] This embodiment provides a method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion, the steps being:

[0075] S1. Casting a magnesium alloy as a shell substrate;

[0076] S2, after the surface of the shell substrate is anodized, nickel-plated;

[0077] S3, after nickel plating, apply antifouling coating to obtain.

[0078] The magnesium alloy, by weight percentage, has the following elemental components: Al: 5%, Zn: 2%, Y: 0.3%, and the balance is Mg.

[0079] The specific steps of the casting are: weighing magnesium ingots, zinc blocks, aluminum blocks and Mg-30Y master alloys according to the weight percentage of the elements of the magnesium alloy, putting them into an induction melting furnace, heating them to 740°C under a protective atmosphere, keeping them warm for 20 minutes after they are completely melted, refining, degassing, deslagging and stirring in sequence, standing and keeping warm for 10 minutes, transferring them to a preheated mold for air cooling and forming, and obtaining a shell substrate.

[0080] The specific steps of the surface anodizing treatment are: fixing the shell substrate on the anode, the cathode is a stainless steel plate, immersing the anode and the cathode in the electrolyte, turning on the power supply, and starting the anodizing; after the oxidation is completed, taking out the shell substrate, washing the residual electrolyte on the surface with deionized water, immersing it in hot water for 20 minutes, and then taking it out and drying it.

[0081] The electrolyte is an oxalic acid aqueous solution, wherein the mass fraction of oxalic acid is 15%.

[0082] The voltage of the anodization is 35V, and the oxidation time is 20min.

[0083] The specific steps of the nickel plating treatment are: fixing the shell substrate after surface anodization treatment on the cathode, the anode is a pure nickel plate, immersing the cathode and the anode in the nickel plating solution, turning on the power supply, and starting electroplating; after electroplating, the nickel plating solution remaining on the surface is rinsed with deionized water, and the nickel plating layer is obtained by drying.

[0084] The thickness of the nickel plating layer is 8 μm.

[0085] The formula of the nickel plating solution is: nickel sulfate: 250 g / L, nickel chloride: 30 g / L, the pH value adjusted by boric acid is 4.0, and the operating temperature is 55°C.

[0086] The antifouling coating is prepared from the following raw materials by weight percentage: 20% fluorocarbon resin, 10% organic silicon resin, 3% modified nano silicon dioxide, 2% polytetrafluoroethylene, and the remainder is supplemented with solvent to 100%.

[0087] The fluorocarbon resin is a first fluorocarbon resin and a second fluorocarbon resin.

[0088] The mass ratio of the first fluorocarbon resin to the second fluorocarbon resin is 1:1.

[0089] The modified nano-silica preparation method comprises the following steps: dispersing the nano-silica evenly in an ethanol aqueous solution, adding a silane coupling agent, stirring at 65° C. for 5 hours, filtering, washing with deionized water for 3 times, and drying at 100° C. to obtain the modified nano-silica.

[0090] The nano silicon dioxide includes first nano silicon dioxide, second nano silicon dioxide and third nano silicon dioxide.

[0091] The mass ratio of the first nano-silicon dioxide, the second nano-silicon dioxide, and the third nano-silicon dioxide is 5:3:1.

[0092] The volume concentration of ethanol in the ethanol aqueous solution is 65%.

[0093] The solid-to-liquid ratio of the nano-silicon dioxide to the ethanol aqueous solution is 1 g:25 mL.

[0094] The silane coupling agent is a mixture of hexamethyldisilazane and gamma-mercaptopropyltrimethoxysilane.

[0095] The mass ratio of the hexamethyldisilazane to γ-mercaptopropyltrimethoxysilane is 5:2.

[0096] The added amount of the silane coupling agent is 25% of the mass of the nano-silicon dioxide.

[0097] The solvent is ethanol.

[0098] The specific steps of applying the antifouling coating are:

[0099] A1. After introducing fluorocarbon resin and silicone resin into the solvent and stirring evenly, add modified nano-silica, continue stirring evenly, add polytetrafluoroethylene, stir evenly, and filter through a 300-mesh filter to obtain an antifouling coating;

[0100] A2. Spray the antifouling coating onto the surface of the shell substrate, put it into an oven and cure it.

[0101] The thickness of the antifouling coating is 2 μm.

[0102] The specific conditions of the curing are: temperature 140° C., and curing time 25 min.

[0103] Example 2

[0104] The difference between this embodiment and embodiment 1 is that the magnesium alloy, by weight percentage, has the following elemental components: Al: 6%, Zn: 3%, Y: 0.5%, and the balance is Mg.

[0105] Example 3

[0106] The difference between this embodiment and embodiment 1 is that the magnesium alloy, by weight percentage, has the following elemental components: Al: 8%, Zn: 1%, Y: 0.3%, and the balance is Mg.

[0107] Comparative Example 1

[0108] The difference between this comparative example and Example 1 is that the magnesium alloy, by weight percentage, has the following elemental components: Al: 5%, Zn: 2%, Y: 2%, and the balance is Mg.

[0109] Comparative Example 2

[0110] The difference between this comparative example and Example 1 is that the elemental composition of the magnesium alloy, by weight percentage, is Al: 5%, Zn: 2%, and the balance is Mg.

[0111] Comparative Example 3

[0112] The difference between this comparative example and Example 1 is that the method for preparing the magnesium alloy shell for a mouse that is resistant to hand sweat corrosion comprises the following steps:

[0113] S1. Casting a magnesium alloy as a shell substrate;

[0114] S2, performing anodizing treatment on the surface of the shell substrate;

[0115] S3. After the surface is anodized, an antifouling coating is applied to obtain the product.

[0116] Comparative Example 4

[0117] The difference between this comparative example and Example 1 is that the fluorocarbon resin is the first fluorocarbon resin.

[0118] Comparative Example 5

[0119] The difference between this comparative example and Example 1 is that the antifouling coating is prepared from raw materials, by weight percentage, of 20% fluorocarbon resin, 10% silicone resin, 3% nano-silicon dioxide, 2% polytetrafluoroethylene, and the solvent is added to make up the balance to 100%.

[0120] Comparative Example 6

[0121] The difference between this comparative example and Example 1 is that the antifouling coating is prepared from raw materials, by weight percentage, of 10% fluorocarbon resin, 20% silicone resin, 3% modified nano-silicon dioxide, 2% polytetrafluoroethylene, and the solvent is added to make up the balance to 100%.

[0122] Comparative Example 7

[0123] The difference between this comparative example and Example 1 is that the nano-silicon dioxide is the first nano-silicon dioxide.

[0124] Performance Testing

[0125] The magnesium alloy shell for mouse that is resistant to hand sweat corrosion obtained in the comparative example is shown in the photo. Figure 1 The cross section of the magnesium alloy shell for mouse which is resistant to hand sweat corrosion obtained in Example 1 was subjected to SEM analysis, and the results are shown in Figure 2 . The artificial sweat test was conducted with reference to QB / T1901.2-93. After being immersed in artificial sweat for 48 hours, the surface was observed for corrosion spots and whether the surface coating was damaged. The salt spray test was conducted with reference to GB / T 12967.3-2022 for 96 hours. The surface was observed for oxidation spots and whether the surface was corroded. Ten people were selected to evaluate the surface roughness and glossiness of the prepared magnesium alloy shell for mouse that was resistant to hand sweat corrosion. The score was 1 to 10 points. The higher the score, the smoother the surface and the better the glossiness. The average of the ten people was taken. The results are shown in Table 1.

[0126] Table 1 Measurement results

[0127]

[0128] According to statistics, the magnesium alloy shell for mouse that can resist hand sweat corrosion prepared by Examples 1 to 3 of the present invention shows significant corrosion resistance under long-term contact with hand sweat and salt spray, with no obvious corrosion marks on the surface, and the coating remains intact, while the surface is smooth and has high gloss. The rare earth Y element content in Comparative Example 1 is too high, so that the second phase precipitated is excessive, which will produce more electrochemical corrosion to the surrounding matrix in a corrosive environment, accelerate local corrosion, thereby greatly reducing the overall corrosion resistance of the magnesium alloy, and also affecting the surface smoothness. Rare earth Y element is not added in Comparative Example 2, Comparative Example 3 is not nickel-plated, Comparative Example 4 does not add the second fluorocarbon resin, Comparative Example 5 does not modify the nano-silicon dioxide, Comparative Example 6 fluorocarbon resin addition is too low, the content of organic silicone resin is too high, and Comparative Example 7 does not add the second nano-silicon dioxide and the third nano-silicon dioxide, and the prepared magnesium alloy shell for mouse that can resist hand sweat corrosion has poor corrosion resistance and low gloss. Therefore, the magnesium alloy shell for mouse that is resistant to hand sweat corrosion and prepared using the raw materials and methods described in this application not only significantly enhances the corrosion resistance of the magnesium alloy, but also provides multiple protection mechanisms for the shell, greatly improving its durability and ability to resist sweat corrosion, effectively extending the service life of the mouse, and ensuring its smooth appearance and comfortable feel.

[0129] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion, characterized in that: The following steps are involved: S1. Casting a magnesium alloy as a shell substrate; S2, after the surface of the shell substrate is anodized, nickel-plated; S3, after nickel plating, apply antifouling coating to obtain; The magnesium alloy, in terms of weight percentage, comprises Al: 3% to 9%, Zn: 1% to 3%, Y: 0.1% to 1%, and the balance is Mg; The antifouling coating is prepared from raw materials including 15% to 25% fluorocarbon resin, 5% to 15% organic silicon resin, 2% to 4% modified nano-silicon dioxide, 1% to 3% polytetrafluoroethylene, and the solvent is added to make up the balance to 100% by weight; The fluorocarbon resin comprises a first fluorocarbon resin and a second fluorocarbon resin, and the mass ratio is 1:(0.5-2); the first fluorocarbon resin has a solid content of 59%-61%, a hydroxyl value of 33-43 mgKOH / g, a number average molecular weight of 12000-16000, an acid value of <1 mgKOH / g, and a viscosity of 500-1000 cp; the second fluorocarbon resin has a solid content of 49%-51%, a hydroxyl value of 49-59 mgKOH / g, a viscosity of 340-500 cp, a fluorine content of 22%-24%, and a number average molecular weight of 15000-20000; The modified nano-silica preparation method comprises the following steps: placing the nano-silica in an ethanol aqueous solution and dispersing it uniformly, adding a silane coupling agent, stirring at 60-70° C. for 4-6 hours, filtering, washing with deionized water for 2-3 times, and drying at 100° C. to obtain the modified nano-silica. The nano-silicon dioxide comprises a first nano-silicon dioxide, a second nano-silicon dioxide and a third nano-silicon dioxide, and the mass ratio is (4-6): (2-4): 1; The first nano-silicon dioxide has an average particle size of 10-20 nm and a specific surface area of ​​240-260 m 2 / g, the packing density is 0.1~0.15g / cm 3 The average particle size of the second nano-silicon dioxide is 25-35 nm, and the specific surface area is 190-210 m 2 / g, the packing density is 0.15~0.18g / cm 3 The average particle size of the third nano-silicon dioxide is 60nm, and the specific surface area is 150~200m 2 / g, the packing density is 0.18~0.2g / cm 3 .

2. The method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion according to claim 1, characterized in that: The specific steps of the casting are: weighing magnesium ingots, zinc blocks, aluminum blocks and Mg-30Y master alloys according to the weight percentage of the elements of the magnesium alloy, putting them into an induction melting furnace, heating them to 700-750°C under a protective atmosphere, keeping them warm for 15-25 minutes after they are completely melted, refining, degassing, deslagging and stirring in sequence, standing and keeping them warm for 8-12 minutes, transferring them to a preheated mold for air cooling and forming, and obtaining a shell substrate.

3. The method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion according to claim 1, characterized in that: The specific steps of the surface anodizing treatment are: fixing the shell substrate on the anode, the cathode is a stainless steel plate, immersing the anode and the cathode in the electrolyte, turning on the power supply, and starting the anodizing; after the oxidation is completed, taking out the shell substrate, washing the residual electrolyte on the surface with deionized water, immersing it in hot water for 15 to 25 minutes, and then taking it out and drying it.

4. The method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion according to claim 3, characterized in that: The voltage of the anodization is 20-50V, and the oxidation time is 18-22min.

5. The method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion according to claim 1, characterized in that: The specific steps of the nickel plating treatment are: fixing the shell substrate after surface anodization treatment on the cathode, the anode is a pure nickel plate, immersing the cathode and the anode in the nickel plating solution, turning on the power supply, and starting electroplating; after electroplating, the nickel plating solution remaining on the surface is rinsed with deionized water, and the nickel plating layer is obtained by drying.

6. The method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion according to claim 5, characterized in that: The thickness of the nickel plating layer is 5-10 μm.

7. The method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion according to claim 6, characterized in that: The formula of the nickel plating solution is: nickel sulfate: 200-300 g / L, nickel chloride: 20-40 g / L, boric acid adjusted pH value to 4.0-4.5, and the use temperature is 50-60°C.

8. The method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion according to claim 7, characterized in that: The thickness of the antifouling coating is 1-3 μm.

9. A magnesium alloy shell for a mouse that is resistant to hand sweat corrosion, prepared according to the method for preparing a magnesium alloy shell for a mouse that is resistant to hand sweat corrosion according to any one of claims 1 to 8.

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