Highly conductive peelable silver paste, method for preparing same and use thereof

Abstract

The application provides a tubing joint manufacturing method and a high-conductivity peelable glue used in the method. The tubing joint has a nested structure and is composed of a tubing joint, a nut and a butt joint part. During electroplating, the tubing joint, the nut and the butt joint part are covered by the peelable glue, and then are electroplated together to form a whole, and finally the peelable glue is removed to complete the integrated processing. The high-conductivity peelable silver glue comprises the following components in parts by weight: chlorovinyl resin: 100 parts, nano silver wire and / or silver particles: 20-300 parts, dispersing agent: 0.15-15 parts. The method can reduce the overall processing efficiency of the tubing joint, greatly shorten the process time, save the process cost and improve the coating quality.

Description

Technical Field

[0001] This disclosure relates to the technical field of electroplating, and in particular to a highly conductive peelable silver paste, its preparation method, and an electroplating method using the same. Background Technology

[0002] Peelable adhesive has strong water resistance, oil resistance, corrosion resistance and insulation. After being sprayed on the surface of an object, it forms a peelable film. Through the effective isolation of the object by the film, it achieves the ideal state of preventing dirt, rust, acid and alkali, scratches and making it look brand new after being torn off.

[0003] Existing peelable adhesives have important applications, such as screen protection for mobile phones and other electronic products, and semiconductor chip packaging. However, existing peelable adhesives focus on environmental protection, peelability, and protective performance, and generally have poor conductivity, which greatly limits their application.

[0004] In fact, peelable adhesives also have important applications in the electroplating of mechanical parts. During the electroplating process, it is sometimes necessary to prevent the formation of a coating on certain areas of the workpiece surface. Current technology generally involves applying a peelable protective layer to these areas to prevent the formation of a coating when the entire workpiece is immersed in the electroplating solution. The peelable protective layer is then removed after the electroplating of the other parts of the workpiece is completed.

[0005] For example, patent CN103421383A discloses a thermosetting peelable blue adhesive for touch screens, which is prepared from the following raw materials: 30-40% vinyl resin, 5-10% alkyd resin, 30-40% amino resin, 15-32% plasticizer, 2-4% filler, and 0.1-3% organic pigment. This peelable adhesive has good acid and alkali resistance, good flexibility, high temperature resistance, and is easy to peel off, but its environmental protection indicators are poor, and its conductivity is also poor, making it unsuitable for the electroplating requirements of composite nested components.

[0006] Patent CN101831135A discloses an elastic peelable adhesive and a method for local electroplating protection thereof. The main resin is a styrene elastomer, but it is not conductive, so its application is somewhat limited.

[0007] Currently, existing methods cannot achieve one-time overall electroplating for two or more workpieces with nested relationships. The process is complex and the coating quality is affected by the nested relationship between the multiple workpieces. Summary of the Invention

[0008] To address the aforementioned issues, this disclosure provides a highly conductive peelable silver paste, its preparation method, and a method for overall electroplating of nested parts using the paste.

[0009] This disclosure provides a highly conductive peelable silver paste comprising the following components by weight: 100 parts of chloroacetic acid resin; 20-200 parts of silver nanowires and / or silver particles, preferably 50-180 parts; and 0.15-15 parts of dispersant, preferably 2-10 parts.

[0010] In some embodiments, the silver nanowires have a length of 10-300 μm, a diameter of 20-100 nm, and a volume resistivity of 0.3 x 10⁻⁶. -5 -0.35xl0 -5 Ω·cm, and / or, the silver particles are composed of one or more of micron-sized silver powder, submicron-sized silver powder, and nano-sized silver powder.

[0011] In some embodiments, when both the silver nanowires and silver particles are included, the weight ratio of the silver nanowires and silver particles is 1:0.5-1:6, preferably 1:2-1:5.

[0012] In some embodiments, the dispersant is at least one of glycerol, ethanol, polyurethane, and dimethyl succinate, preferably dimethyl succinate.

[0013] In some embodiments, the product further includes at least one of the following components based on 100 parts by weight of chloroacetic acid resin: 1 to 40 parts of plasticizer, preferably 4 to 30 parts; 1 to 20 parts of thickener, preferably 3 to 18 parts; 1 to 20 parts of lubricant, preferably 3 to 12 parts; and 0.4 to 10 parts of thixotropic agent, preferably 0.5 to 5 parts.

[0014] In some embodiments, the plasticizer is at least one of phthalate, polyethylene glycol (preferably PEG200), glycerin, and tributyl citrate, preferably at least one of phthalate, and more preferably dipropylheptyl phthalate.

[0015] In some embodiments, the thickener is at least one of sodium carboxymethyl cellulose, guar gum, carrageenan, and cyclodextrin, preferably sodium carboxymethyl cellulose.

[0016] The thixotropic agent is at least one of amide wax, silica, organobentonite, hydrogenated castor oil, and fumed silica, preferably silica.

[0017] The lubricant is at least one of calcium stearate, barium stearate, oxidized polyethylene wax, glyceryl stearate, stearic acid, paraffin wax, and polyethylene wax, preferably glyceryl stearate.

[0018] In some embodiments, the highly conductive peelable silver paste may also include some commonly used additives, such as organic pigments, which are 0.1-3 parts by weight of chlorinated vinyl resin as a base of 100 parts by weight.

[0019] In some embodiments, the chloroacetic acid resin is a copolymer, preferably a binary chloroacetic acid resin copolymer.

[0020] The conductive silver paste described in this invention does not cure below 30°C, especially at room temperature. It can cure rapidly at high temperatures, preferably between 60 and 180°C, more preferably between 90 and 160°C, and most preferably 150°C. For example, the conductive silver paste of this invention can achieve good strength after curing for 1 minute at 150°C.

[0021] The conductive silver paste described in this invention exhibits excellent conductivity after curing into a film, with a volume resistivity of less than 6 x 10⁻⁶. -3 Ω·cm, preferably below 5.5 x l0 -3 Ω·cm. It can serve as an excellent protective film for electroplating without affecting the electroplating reaction of the parts.

[0022] This disclosure also provides a method for preparing the above-mentioned highly conductive peelable silver paste, comprising the following steps:

[0023] Weigh the components, including the chloroacetic acid resin, according to the stated weight proportions and mix them evenly to obtain a first mixture;

[0024] Weigh the silver nanowires and / or silver particles and the dispersant according to the specified weight proportions, add them to the first mixture above, and then mix them evenly to obtain highly conductive peelable silver paste.

[0025] In some embodiments, after uniformly mixing silver nanowires and / or silver particles with a dispersant to obtain a second mixture, the second mixture is added to the first mixture in multiple batches and mixed evenly to obtain a highly conductive peelable silver paste.

[0026] The preparation method of the highly conductive peelable silver paste disclosed herein can be achieved using various conventional mixing equipment, such as dispersers, kneaders, mixers, and screw extruders. The mixing speed and time can be set using standard parameters from existing mixing methods.

[0027] This disclosure also provides an electroplating method for composite nested components, the composite nested components including a first component and a second component, the second component being nested in a first position of the first component, including the following steps:

[0028] A conductive protective layer is formed at the first location, the conductive protective layer being formed of highly conductive peelable silver paste as described above;

[0029] After the conductive protective layer has cured, the second component and the first component are nested in the first position and fixed in contact with the conductive protective layer.

[0030] The first and second components are immersed in an electroplating solution for electroplating.

[0031] In some embodiments, the composite nested component is a high-pressure oil pipe for an aircraft engine, the first component is an oil pipe, the second component is a nut, the first position is the oil nozzle of the oil pipe, the nut is nested in the oil nozzle of the oil pipe, the oil nozzle is located at the end of the oil pipe and its outer diameter is larger than the inner diameter of the nut.

[0032] In some embodiments, after the conductive protective layer has cured, the step of nesting the second component and the first component in the first position includes: moving the nut to the oil nozzle of the oil pipe so that one end of the nut contacts the conductive protective layer, and inserting the insulating plug into the nut from the other end of the nut and abutting against the front end of the oil nozzle.

[0033] The conductive protective layer of the conductive silver paste described in this invention can be rapidly cured at high temperatures, typically 60–180°C, preferably 90–160°C, and more preferably 150°C.

[0034] In some embodiments, the insulating plug is an insulating threaded plug having an external thread that mates with the internal thread of the nut. The insulating threaded plug can be screwed into the nut until it abuts against the front end of the grease fitting to nest and fix the nut on the oil pipe.

[0035] This disclosure also provides the application of highly conductive peelable silver paste as described in any of the foregoing in electroplating.

[0036] This disclosure provides a highly conductive peelable silver paste and its preparation method, which greatly improves its conductivity and broadens the application range of peelable adhesives. Furthermore, this disclosure also provides a method for electroplating composite nested components using this peelable adhesive, which can complete both component protection and conductive electroplating processes in one step, significantly shortening process time, saving process costs, and improving coating quality.

[0037] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1This is a simplified structural diagram of the high-pressure oil pipe of an aero-engine in an embodiment of this disclosure.

[0040] Figure 2 This is a simplified structural diagram of the oil pipe in an embodiment of this disclosure.

[0041] Figure 3 This is a simplified structural diagram of the nozzle forming a conductive protective layer in an embodiment of this disclosure.

[0042] Figure 4 This is a simplified diagram of the nested and fixed structure of the high-pressure oil pipe of the aero-engine during electroplating in an embodiment of this disclosure.

[0043] Explanation of reference numerals in the attached figures:

[0044] 1. Oil pipe; 1.1. Middle section of oil pipe; 1.2. Oil nozzle;

[0045] 2. Nuts;

[0046] 3. Conductive protective layer;

[0047] 4. Insulating threaded plug. Detailed Implementation

[0048] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0049] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0050] In the description of this disclosure, it should be understood that the use of terms such as "first" and "second" is merely for the purpose of distinction, and unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this disclosure.

[0051] Furthermore, the technical features involved in the different embodiments of this disclosure described below can be combined with each other as long as they do not conflict with each other.

[0052] This disclosure provides a highly conductive peelable silver paste comprising the following components by weight: 100 parts of chloroacetic acid resin; 20-200 parts, preferably 50-180 parts, of silver nanowires and / or silver particles; 0.15-15 parts, preferably 2-10 parts, of dispersant; 1-40 parts, preferably 4-30 parts, more preferably 4.5-25 parts, of plasticizer; 1-20 parts, preferably 3-18 parts, more preferably 3-12 parts, of thickener; 1-20 parts, preferably 3-12 parts, more preferably 3-10 parts, of lubricant; and 0.4-10 parts, preferably 0.5-5 parts, more preferably 0.5-2 parts, of chloroacetic acid resin as a matrix. By adding conventional fillers and silver nanowires and / or smaller silver particles according to the above weight proportions, a highly conductive peelable silver paste can be obtained, which can be applied in electroplating processes. The electroplating process described in this invention can employ existing electroplating processes, including but not limited to existing electroplating equipment and process parameters. For example, using a conventional nickel plating process with medium-speed stirring, the temperature is 50℃, pH is 11, current density is 2A / m2, and time is 1h.

[0053] It should be noted that all raw materials mentioned in this disclosure are conventional raw materials under their respective functional categories, and commercially available qualified products that meet the requirements can fulfill the requirements. Among them, the chloroacetic acid resin is a binary chloroacetic acid resin, which can be selected from the domestic Xinfeng Chemical Co., Ltd. chloroacetic acid binary copolymer series or the imported Korean Hanwha Chemical Co., Ltd. model KCM-12 or KCH-12 chloroacetic acid resin; or the German Vinolit E70LF chloroacetic acid resin, etc.

[0054] Because nanoparticles are highly reactive and have high interfacial tension, they are prone to aggregation. Therefore, specific dispersants are needed to alleviate the aggregation problem. Even in the presence of a dispersant, high-speed mechanical stirring is still required for pre-dispersion. Commonly available dispersants can be selected, such as at least one from glycerol, ethanol, polyurethane, and dimethyl succinate, to uniformly disperse the conductive particles in the matrix.

[0055] In some embodiments, the silver nanowires have a length of 10-300 μm, a diameter of 20-100 nm, and a volume resistivity of 0.3 x 10⁻⁶. -5 -0.35xl0 -5 Ω·cm; preferably, silver nanowires synthesized by solvothermal method.

[0056] In some embodiments, the silver particles in the silver nanowires and / or sub-nanometer silver particles are composed of one or more of micron-sized silver powder, submicron-sized silver powder, and nano-sized silver powder.

[0057] In some embodiments, when both the silver nanowires and silver particles are included, the weight ratio of the silver nanowires and silver particles is 1:0.5-1:6, preferably 1:2-1:5.

[0058] In some embodiments, the plasticizer is at least one of phthalate, polyethylene glycol (such as PEG200), glycerin, and tributyl citrate, preferably at least one of phthalate, and more preferably dipropylheptyl phthalate.

[0059] In some embodiments, the thickener is at least one of sodium carboxymethyl cellulose, guar gum, carrageenan, and cyclodextrin, preferably sodium carboxymethyl cellulose.

[0060] In some embodiments, the thixotropic agent is at least one of amide wax, silica, organobentonite, hydrogenated castor oil, and fumed silica, preferably silica.

[0061] In some embodiments, the lubricant is at least one of calcium stearate, oxidized polyethylene wax, glyceryl stearate, stearic acid, paraffin wax, and polyethylene wax, preferably glyceryl stearate.

[0062] In some embodiments, the conductive silver paste of the present invention may further include pigments. The pigments are preferably organic pigments, with 100 parts of chlorinated vinyl acetate resin and the amount of pigment used being 0.1-3 parts.

[0063] The preparation examples of the above-mentioned highly conductive peelable silver paste are as follows. The highly conductive peelable silver paste with the corresponding weight composition can be obtained according to the following examples:

[0064] raw material:

[0065] Matrix: Dichloroethylene vinyl acetate resin, brand name: PA13845, manufacturer: Arkema, France;

[0066] Dispersant: Glycerin;

[0067] Lubricant, calcium stearate, grade: C113301, manufacturer: Luchuan Chemical Co., Ltd.;

[0068] Silver nanowires: Commercially available standard silver nanowires (length 10-300μm, diameter 20-100nm, volume resistivity 0.3x10⁻⁶). -5 -0.35xl0 -5 Ω·cm);

[0069] Silver particles: Flaky micron-sized silver powder, grade: FAgl-8960 (average particle size 7 microns); grade: Nano silver powder Sag-5 (particle size less than 100 nanometers), manufacturer: Guizhou Guoyan Baiye Co., Ltd.; Micron-sized silver particles (particle size 10μm, commercially available).

[0070] All other components are commercially available.

[0071] The volume resistivity testing method for the conductive silver paste cured into a film according to this invention is based on the standard GB / T15662-1995. The film-forming temperature can be 150℃, and the thickness is generally controlled between 100-300 micrometers.

[0072] The peel strength test standard for the conductive silver paste of this invention after curing into a film refers to Method 1 of GB2792-2014. The conductive silver paste of this invention is screen-printed onto a stainless steel metal substrate and baked at 150°C for 10 minutes to form a film. Then, the 180° peel strength of the film against the metal is tested, with the unit being "Nm". -1 (i.e., N / m).

[0073] Example 1

[0074] Weigh out 100 parts by weight of dichlorovinyl acetate resin, 9 parts of dipropylheptyl phthalate (DPHP), 0.9 parts of polyamide wax, 3.6 parts of glyceryl stearate, and 3 parts of sodium carboxymethyl cellulose, and add them to a disperser. Stir and disperse at 400 rpm for 30 minutes.

[0075] Weigh out 20 parts by weight of the mixture of nano-silver wires, 45 parts by weight of flake-shaped micron silver powder and 0.4 parts by weight of glycerin, add it to the disperser in multiple batches, and stir and disperse at 500 rpm / min for 40 min to obtain highly conductive peelable silver paste.

[0076] The volume resistivity and peel strength of the conductive silver paste cured into a film according to the present invention are shown in Table 1.

[0077] Example 2

[0078] Weigh out 100 parts by weight of binary vinyl chloride resin, 8.3 parts of DPHP, 0.8 parts of polyamide wax, 8.3 parts of barium stearate, and 12 parts of sodium carboxymethyl cellulose, and add them to a disperser. Stir and disperse at 400 rpm for 25 minutes.

[0079] Weigh 108 parts by weight of the mixture of flake-shaped micron silver powder and 4 parts by weight of glycerin, add it to the disperser in multiple batches, and stir and disperse at 600 rpm / min for 55 min to obtain highly conductive peelable silver paste.

[0080] The volume resistivity and peel strength of the conductive silver paste cured into a film according to the present invention are shown in Table 1.

[0081] Example 3

[0082] Weigh out 100 parts by weight of binary chloroacetic acid resin, 17 parts of DPHP, 15 parts of sodium carboxymethyl cellulose, 1.7 parts of amorphous silica and 6.7 parts of calcium stearate, add them to a disperser and stir and disperse at 300 rpm for 20 min.

[0083] Weigh 233 parts by weight of the mixture of micron-sized silver particles and 10 parts by weight of glycerin and add it to the disperser in multiple batches. Stir and disperse at 600 rpm / min for 60 min to obtain highly conductive peelable silver paste.

[0084] The volume resistivity and peel strength of the conductive silver paste cured into a film according to the present invention are shown in Table 1.

[0085] Example 4

[0086] Weigh out 100 parts by weight of dichloroacetic acid resin, 24 parts of DPHP, 2 parts of amorphous silica, 12 parts of glyceryl stearate, and 20 parts of cyclodextrin, and add them to a disperser. Stir and disperse at 250 rpm for 30 min.

[0087] Weigh 140 parts by weight of the mixture of silver nanowires and 4 parts by weight of dimethyl succinate and add it to the disperser in multiple batches. Stir and disperse at 350 rpm / min for 45 min to obtain highly conductive peelable silver paste.

[0088] The volume resistivity and peel strength of the conductive silver paste cured into a film according to the present invention are shown in Table 1.

[0089] Example 5

[0090] Weigh out 100 parts by weight of binary chloroacetic acid resin, 6.7 parts of DPHP, 2.2 parts of amorphous silica, 6.7 parts of glyceryl stearate, and 18 parts of sodium carboxymethyl cellulose, and add them to a disperser. Stir and disperse at 300 rpm for 30 min.

[0091] Weigh 111 parts by weight of the mixture of micron-sized silver particles and 5.5 parts by weight of dimethyl succinate and add it to the disperser in multiple batches. Stir and disperse at 450 rpm / min for 50 min to obtain highly conductive peelable silver paste.

[0092] The volume resistivity and peel strength of the conductive silver paste cured into a film according to the present invention are shown in Table 1.

[0093] Example 6

[0094] Weigh out 100 parts by weight of binary chloroacetic acid resin, 7.5 parts of DPHP, 3.8 parts of amorphous silica, 5 parts of glyceryl stearate, and 3 parts of sodium carboxymethyl cellulose, and add them to a disperser. Stir and disperse at 300 rpm for 30 min.

[0095] Weigh out 37.5 parts of nano-silver wire, 112 parts of nano-silver powder and 8 parts of dimethyl succinate according to the specified weight, add the mixture to the disperser in multiple batches, and stir and disperse at a speed of 460 rpm / min for 55 min to obtain highly conductive peelable silver paste.

[0096] The volume resistivity and peel strength of the conductive silver paste cured into a film according to the present invention are shown in Table 1.

[0097] Example 7

[0098] Weigh out 100 parts by weight of the dichloroacetic acid resin, 4.6 parts of DPHP, 18 parts of cyclodextrin, 2.3 parts of amide wax and 3 parts of calcium stearate, and add them to a disperser. Stir and disperse at 550 rpm for 30 minutes.

[0099] The mixture of 15 parts by weight of silver nanowires, 62 parts by weight of silver micron particles and 2.3 parts by weight of dimethyl succinate was added to the disperser in multiple batches and stirred and dispersed at 480 rpm / min for 55 min to obtain highly conductive peelable silver paste.

[0100] The volume resistivity and peel strength of the conductive silver paste cured into a film according to the present invention are shown in Table 1.

[0101] Example 8

[0102] Weigh out 100 parts by weight of dichloroacetic acid resin, 6 parts of DPHP, 12 parts of cyclodextrin, 5 parts of amide wax and 3 parts of calcium stearate, add them to a disperser and stir and disperse at 400 rpm / min for 30 min.

[0103] Weigh out 65 parts by weight of the mixture of silver nanowires and 4 parts by weight, add it to the disperser in multiple batches, and stir and disperse at 480 rpm / min for 55 min to obtain highly conductive peelable silver paste.

[0104] The volume resistivity and peel strength of the conductive silver paste cured into a film according to the present invention are shown in Table 1.

[0105] Example 9

[0106] Weigh out 100 parts by weight of dichloroacetic acid resin, 6 parts of DPHP, 12 parts of cyclodextrin, 5 parts of amide wax and 3 parts of calcium stearate, add them to a disperser and stir and disperse at 400 rpm / min for 30 min.

[0107] A mixture of 65 parts by weight of micron-sized silver particles and 4 parts by weight of glycerol was weighed and added to the disperser in multiple batches. The mixture was stirred and dispersed at 480 rpm / min for 55 min to obtain a highly conductive peelable silver paste. The volume resistivity and peel strength of the conductive silver paste cured into a film according to the present invention are shown in Table 1.

[0108] Comparative Example 1

[0109] Except for the absence of silver nanowires, everything else was the same as in Example 4. The volume resistivity and peel strength of the resulting adhesive film after curing are shown in Table 1.

[0110] Comparative Example 2

[0111] Commercially available thermoplastic styrene rubber (purchased from Kraton Polymers, Inc., USA) was used for direct coating. The volume resistivity and peel strength of the resulting cured film are shown in Table 1.

[0112] In addition, it should be noted that other fillers, such as pigments, may be added during the preparation process as needed to obtain other additional properties. This aspect belongs to the existing preparation process and will not be elaborated in this disclosure.

[0113] In Examples 1-7, silver nanowires and / or silver particles smaller than nanometers and the dispersant can be added to the disperser all at once and stirred. Due to the large quantity, the gel can be formed by increasing the stirring time and speed. To improve the preparation efficiency, the two can be mixed and added to the disperser in multiple uniform batches, which can more efficiently prepare the peelable gel.

[0114] The highly conductive peelable silver paste obtained according to the raw materials and components specified in this disclosure exhibits superior physical properties, including good viscosity and thixotropic properties, and moderate peel strength. It is well-suited for localized protection during electroplating and subsequently peels off effectively without residue. The preferred peel strength of the highly conductive peelable silver paste of this invention is 1–15 Nm. -1 Preferably 1.5~12Nm -1 More preferably 3~11.5Nm -1 When the peel force is 1-15 Nm -1 When there is no residue after peeling, the adhesion and peelability are good. When the peeling force is less than 1 Nm, the adhesion and peelability are good. -1 It can be peeled off without residue but has poor adhesion; when the peeling force is greater than 15 Nm -1 Sometimes, the adhesion is so good that it is difficult to peel off and leaves residue.

[0115] Among its key features, the viscosity ensures the coating application is adequate, while the thixotropy allows for adaptation to the surface conditions of the object being coated. Furthermore, its excellent peel strength ensures easy and undamaged removal after the protective function is completed. Finally, the product's low sheet resistance guarantees good conductivity, making it suitable for one-time electroplating processes of composite nested parts, or other processes requiring peelable conductive adhesives.

[0116]

[0117] Glass coated with the conductive silver paste of this invention was baked at 150°C for 10 minutes and then removed. Observation revealed no edge pinholes or film cracks, and the film was dry. The film-forming properties were good.

[0118] This disclosure also provides an electroplating method for composite nested components, wherein the composite nested components include a first component and a second component, and the second component is nested in a first position of the first component.

[0119] The electroplating method includes the following steps:

[0120] A conductive protective layer is formed at the first position. The conductive protective layer is obtained by curing the above-mentioned highly conductive peelable silver paste. Specifically, the first position of the first component can be immersed in highly conductive peelable silver paste, or coated (preferably sprayed) with highly conductive peelable silver paste, then dried, and then cured at a temperature of 60-180°C, preferably 90-160°C, so that a conductive protective layer obtained by curing the highly conductive peelable silver paste of the present invention is formed at the first position. The thickness of the conductive protective layer is not limited, as long as it completely covers the first position.

[0121] After the conductive protective layer has cured, the second component and the first component are nested in the first position;

[0122] The first and second components are immersed in an electroplating solution for electroplating.

[0123] The composite nested components described in this disclosure refer to combined components with nested connection relationships between parts. These components are nested together after molding, such as high-pressure oil pipes for aero engines. Figure 1-2 As shown, the high-pressure oil pipe of the aircraft engine includes an oil pipe 1 and a nut 2. After the two are finally combined, the nut 2 is nested on the oil pipe 1, and the end of the oil pipe 1 has an oil nozzle 1.2. The diameter of the oil nozzle 1.2 is larger than that of the middle section 1.1 of the oil pipe. The inner diameter of the nut is larger than that of the middle section 1.1 of the oil pipe and smaller than that of the oil nozzle 1.2, so that the nut 2 can move in the middle section 1.1 of the oil pipe but cannot be dislodged from the oil nozzle 1.2.

[0124] like Figure 3 As shown, during the electroplating process for high-pressure oil pipes in aero-engines, the outer surface of the oil nozzle 1.2 is first covered with the highly conductive peelable silver paste provided in this disclosure, forming a conductive protective layer 3 on the outer surface of the oil nozzle 1.2. The conductive protective layer 3 can be formed by coating the highly conductive peelable silver paste onto the outer surface of the oil nozzle 1.2 and curing it, or by immersing the oil nozzle 1.2 in the highly conductive peelable silver paste and then curing it. The peelable adhesive substrate material is a thermoplastic material. When the mixed sample is placed in a drying oven at a temperature below 30°C, curing will not occur. After actual construction, placing the material at 150°C for 1 minute yields good strength. The recommended curing temperature is 60-180°C, preferably 90-160°C, and most preferably 150°C.

[0125] like Figure 4As shown, after the conductive protective layer 3 is formed, the nut 2 is moved to the oil nozzle 1.2 and pressed down, so that one end of the nut 2 contacts the conductive protective layer. Then, the insulating threaded plug 4 is screwed into the nut 2 from the other end and abuts against the front end of the oil nozzle 1.2. The insulating threaded plug 4 has an external thread that can engage with the internal thread of the nut 2. During assembly, the insulating threaded plug 4 is screwed into the nut 2 until it abuts against the front end of the oil nozzle 1.2. At this point, the nut 2 is fixed to the oil nozzle 1.2 position of the oil pipe 1 by the insulating threaded plug 4, and one end of the nut 2 is in close contact with the conductive protective layer 3 and is conductive.

[0126] Alternatively, other insulating plugs with fixing functions, such as rubber plugs, can be used here. These plugs have a certain degree of elasticity and can expand after being immersed in the nut to make contact with the inside of the nut 2 and the front end of the grease nipple 1.2, thereby achieving nesting and fixing. In addition, any insulating fastener that can achieve this function is within the protection scope of this disclosure.

[0127] Based on the nested fixing, the entire high-pressure oil pipe of the aircraft engine can be immersed in the electroplating solution during the electroplating process. Relying on this nested and conductive relationship, the nut 2 and the oil pipe 1 can be electroplated in one go. After the electroplating is completed, the insulating threaded plug 4 is removed and fixed in contact. The conductive protective layer 3 is peeled off to obtain the high-pressure oil pipe of the aircraft engine without an electroplating layer at the oil nozzle 1.2.

[0128] The system completes both component protection and conductive electroplating processes in one step, significantly reducing process time, saving costs, and improving coating quality.

[0129] The above description is merely an exemplary embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. An electroplating method for a composite nested component, the composite nested component comprising a first component and a second component, the second component being nested at a first position of the first component, comprising the following steps: A conductive protective layer is formed at the first location, the conductive protective layer being formed by curing highly conductive peelable silver paste; After the conductive protective layer has cured, the second component and the first component are nested in the first position and fixed in contact with the conductive protective layer. The first component and the second component are immersed in an electroplating solution for electroplating. The highly conductive peelable silver paste is made from the following components in parts by weight: Acetate chlorination resin: 100 parts; Silver nanowires and / or silver particles: 20-300 parts; Dispersant: 0.15-15 parts; The chlorinated vinyl resin is a binary chlorinated vinyl resin copolymer; The silver nanowires have a length of 10-300 μm, a diameter of 20-100 nm, and a volume resistivity of 0.3 x 10⁻⁶. -5 -0.35x10 -5 Ω·cm; The silver particles are composed of one or more of the following: micron-sized silver powder, submicron-sized silver powder, and nano-silver powder. The dispersant is at least one of glycerol, ethanol, polyurethane, and dimethyl succinate.

2. The electroplating method for composite nested components according to claim 1, characterized in that, The composite nested component is a high-pressure oil pipe for an aircraft engine. The first component is the oil pipe, and the second component is a nut. The first position is the oil nozzle of the oil pipe. The nut is nested inside the oil nozzle of the oil pipe. The oil nozzle is located at the end of the oil pipe and its outer diameter is larger than the inner diameter of the nut; and / or, The curing temperature of the highly conductive peelable silver paste is 60–180°C.

3. The electroplating method for composite nested components according to claim 2, characterized in that, The curing temperature of the highly conductive peelable silver paste is 90–160°C.

4. The electroplating method for composite nested components according to claim 2, characterized in that, After the conductive protective layer has cured, the second component and the first component are nested in the first position, including: moving the nut to the oil nozzle of the oil pipe so that one end of the nut contacts the conductive protective layer, and inserting the insulating plug into the nut from the other end of the nut and abutting against the front end of the oil nozzle.

5. The electroplating method for composite nested components according to claim 4, characterized in that, The insulating plug is an insulating threaded plug with an external thread that mates with the internal thread of the nut. The insulating threaded plug can be screwed into the nut until it abuts against the front end of the grease fitting to nest and fix the nut on the oil pipe.

6. The electroplating method for composite nested components according to claim 1, characterized in that, The highly conductive peelable silver paste is made from the following components in parts by weight: Acetate chlorination resin: 100 parts; Silver nanowires and / or silver particles: 50-250 parts; Dispersant: 2-10 parts.

7. The electroplating method for composite nested components according to claim 1, characterized in that, When the nanowires and silver particles are included, the weight ratio of the nanowires and silver particles is 1:0.5-1:

6.

8. The electroplating method for composite nested components according to claim 7, characterized in that, When the nanowires and silver particles are included, the weight ratio of the nanowires and silver particles is 1:2 to 1:

5.

9. The electroplating method for composite nested components according to claim 1, characterized in that, It also includes at least one of the following components based on 100 parts by weight of chloroacetic acid resin: plasticizer: 1-40 parts; Thickener: 1-20 parts; Lubricant: 1-20 parts; Thixotropic agent: 0.4-10 parts.

10. The electroplating method for the composite nested components according to claim 9, characterized in that, It also includes at least one of the following components based on 100 parts by weight of chloroacetic acid resin: plasticizer: 4-30 parts; Thickener: 3-18 parts; Lubricant: 3-12 parts; Thixotropic agent: 0.5-5 parts.

11. The electroplating method for composite nested components according to claim 9, characterized in that, The plasticizer is at least one selected from phthalate, polyethylene glycol, glycerin, and tributyl citrate; and / or, The thickener is at least one selected from sodium carboxymethyl cellulose, guar gum, carrageenan, and cyclodextrin; and / or, The thixotropic agent is at least one selected from amide wax, silica, organobentonite, hydrogenated castor oil, and fumed silica; and / or... The lubricant is at least one of calcium stearate, barium stearate, oxidized polyethylene wax, glyceryl stearate, stearic acid, paraffin wax, and polyethylene wax.

12. The electroplating method for composite nested components according to claim 11, characterized in that, The plasticizer is at least one of phthalates; and / or The thickener is sodium carboxymethyl cellulose; and / or, The thixotropic agent is silicon dioxide; and / or, The lubricant is glyceryl stearate.

13. The electroplating method for the composite nested components according to claim 12, characterized in that, The plasticizer is dipropylheptyl phthalate.

14. The electroplating method for the composite nested components according to any one of claims 1-13, characterized in that, The preparation method of the highly conductive peelable silver paste includes the following steps: Weigh the components, including the chloroacetic acid resin, according to the stated weight proportions and mix them evenly to obtain a first mixture; First, the silver nanowires and / or silver particles are uniformly mixed with the dispersant to obtain a second mixture; The second mixture is then added to the first mixture in multiple batches and mixed evenly to obtain a highly conductive peelable silver paste.

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