High-thermal-conductivity copper-based profiled bar for high-voltage electric appliance and preparation method thereof

Abstract

The invention discloses a high-thermal-conductivity copper-based profiled bar for a high-voltage electric appliance and a preparation method of the high-thermal-conductivity copper-based profiled bar, and relates to the technical field of copper-based materials. The method comprises the following steps: 1, sequentially carrying out alkali washing and acid washing on a copper-based profiled bar to obtain a pretreated copper-based profiled bar; 2, the pretreated copper-based profiled bar is placed in a pre-plating solution for pre-plating; and transferring into a silver plating solution for electroplating to obtain the high-thermal-conductivity copper-based profiled bar. The silver plating solution comprises the following components: 8-12 g / L of silver nitrate, 80-100 g / L of sodium potassium tartrate tetrahydrate, 60-80 mL / L of ammonia water, 0.5-1 g / L of modified polyethyleneimine, 1-1.5 g / L of 5, 5-dimethyl hydantoin, 8-10 g / L of boron-doped silicon carbide and a solvent of deionized water. According to the high-thermal-conductivity copper-based profiled bar obtained in the application, the electrical conductivity is effectively ensured on the basis of improving the thermal conductivity.

Description

Technical Field

[0001] The present invention relates to the technical field of copper-based materials, and specifically to a high thermal conductivity copper-based profile for high-voltage electrical appliances and a preparation method thereof. Background Art

[0002] High-voltage electrical appliances are crucial equipment in modern power industry; their performance reliability and stability directly affect safe operation. Among them, during the operation of high-voltage electrical appliances, due to the action of current or generation of a large amount of heat, if the heat cannot be dissipated in time, the excessive temperature will increase the probability of electrical appliance failure, cause equipment aging, and affect the service life.

[0003] Copper-based materials have been widely used in the field of high-voltage electrical appliances due to their good electrical conductivity and relatively good thermal conductivity. However, due to the high-power and high-load operation requirements of high-voltage electrical appliances, the thermal conductivity of ordinary copper-based materials needs to be further improved to cope with more demanding working environments. The common way to improve or enhance performance is to set a coating layer on its surface through electroplating process; however, in the prior art, the coating layer is generally set for relatively regular copper-based materials, such as copper plates, copper rods, etc.; for the coating of copper-based profiles, due to the irregularity of the graphics, there are problems such as uneven surface coating in areas such as corners and poor adhesion of the coating interface, resulting in a decrease in the yield rate. On the other hand, when the coating layer improves the thermal conductivity, it generally introduces thermally conductive nanoparticles, which have problems such as dispersibility and interface with the metal layer, and there are certain defects that hinder conduction, resulting in an increase in internal resistance and a decrease in electrical conductivity.

[0004] In summary, to solve the above problems, it is of great significance to prepare a high thermal conductivity copper-based profile for high-voltage electrical appliances. Summary of the Invention

[0005] The purpose of the present invention is to provide a high thermal conductivity copper-based profile for high-voltage electrical appliances and a preparation method thereof to solve the problems raised in the above background art.

[0006] To solve the above technical problems, the present invention provides the following technical solutions:

[0007] A preparation method of a high thermal conductivity copper-based profile for high-voltage electrical appliances includes the following steps:

[0008] Step 1: Alkaline wash and acid wash the copper-based profile in sequence to obtain a pretreated copper-based profile;

[0009] Step 2: Pretreat the copper-based profile in a pre-plating solution; transfer it to a silver plating solution for electroplating to obtain a high thermal conductivity copper-based profile.

[0010] Preferably, the caustic solution for caustic washing is an aqueous sodium hydroxide solution with a concentration of 8 - 10 g / L, and the caustic washing time is 10 - 30 minutes; the acid solution for pickling is an aqueous sulfuric acid solution with a concentration of 140 - 150 mL / L, and the pickling time is 10 - 30 minutes.

[0011] Preferably, the pre - plating solution contains the following components: silver nitrate 0.5 - 1 g / L, thiourea 2 - 3 g / L, sodium citrate 50 - 60 g / L, and the solvent is deionized water; the process parameters for pre - plating are: temperature 10 - 35 °C, current density 0.2 - 0.5 A / dm2, and electroplating time 10 - 30 seconds.

[0012] Preferably, the silver - plating solution contains the following components: silver nitrate 8 - 12 g / L, potassium sodium tartrate 80 - 100 g / L, ammonia water 60 - 80 mL / L, modified polyethyleneimine 0.5 - 1 g / L, 5,5 - dimethylhydantoin 1 - 1.5 g / L, boron - doped silicon carbide 8 - 10 g / L, and the solvent is deionized water.

[0013] Preferably, the process parameters for electroplating are: temperature 20 - 30 °C, current density 0.5 - 0.8 A / dm2, electroplating time 1 - 1.5 hours, and stirring rate 600 - 700 r / min.

[0014] Preferably, the preparation method of the modified polyethyleneimine is as follows: under a nitrogen atmosphere, nonylphenol polyoxyethylene ether and thionyl chloride are successively added to chloroform, and at 30 - 40 °C, a 0.06 - 0.1 mol / L sodium hydroxide solution is added dropwise for neutralization, and the mixture is stirred and reacted for 2 - 3 hours; polyethyleneimine - chloroform and 3 - chloropropyltriethoxysilane - chloroform are added; the temperature is raised to 45 - 55 °C, and the mixture is stirred and reacted for 24 hours, then washed and dried to obtain the modified polyethyleneimine.

[0015] Preferably, the modified polyethyleneimine contains the following raw materials: 20 parts of polyethyleneimine, 3 - 4 parts of nonylphenol polyoxyethylene ether, 1.2 - 1.5 parts of thionyl chloride, and 1 - 2 parts of 3 - chloropropyltriethoxysilane.

[0016] Preferably, the preparation method of the boron - doped silicon carbide is as follows: sucrose, silica sol, 2 - methyl - 4 - pyridineboronic acid, and palladium nitrate are successively added to the solvent, and hydrothermal reaction is carried out at 150 - 200 °C for 5 - 6 hours, then filtered and dried, placed under a nitrogen atmosphere, and reduction reaction is carried out at 1000 - 1500 °C for 10 - 12 hours, and then cooled; the product is placed under an air atmosphere and calcined at 500 - 800 °C for 3 - 6 hours, cooled, washed, and dried to obtain the boron - doped silicon carbide.

[0017] Preferably, in the raw materials of the boron-doped silicon carbide, the mass ratio of sucrose, silica sol, 2-methyl-4-pyridineboronic acid, and palladium nitrate is 15:(10-12):(0.2-0.5):(0.2-0.3).

[0018] A highly thermally conductive copper-based profile for high-voltage electrical appliances prepared by a preparation method of a highly thermally conductive copper-based profile.

[0019] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0020] In the solution, in order to improve the coating uniformity and the yield of the copper-based profile, by limiting the relevant components of the pre-plating solution and cooperating with each other, it is possible to provide a stable supply of silver ions for the silver plating process, control the reduction rate and crystal growth of silver ions, and inhibit the influence of impurities, thereby obtaining a silver plating layer with good quality and laying a foundation for the subsequent silver plating process.

[0021] In the solution, in order to improve the surface stability of the copper-based profile, a silver plating solution with specific components and ratios is set in the solution to effectively improve the surface stability and the safety of high-voltage electrical appliances. Among them, in order to improve the strength and thermal conductivity of the coating, boron-doped silicon carbide is introduced into the silver plating solution; silicon carbide has a high thermal conductivity, and the interface between silicon carbide and silver is good. Its introduction in the silver coating can serve as a bridge for heat conduction and form more heat conduction paths with silver, which helps heat transfer. At the same time, the introduction of silicon carbide can promote the preferred orientation of the silver plating layer towards the (220) plane, and can also effectively hinder dislocation slip and grain boundary slip, improving the comprehensive properties such as the electrical conductivity and strength of the coating. However, if the amount of silicon carbide introduced is too large or the dispersion is uneven, it will cause local segregation, which will not only affect the thermal conductivity but also the electrical conductivity. Therefore, in the solution, first, boron-doped silicon carbide is used instead of conventional silicon carbide because after boron atoms are doped, the crystal structure and electronic state of silicon carbide can be changed, which indirectly has a positive impact on heat conduction. Appropriate boron doping can reduce crystal defects and impurity scattering, promote phonon transmission, and thus improve heat conduction. At the same time, during the preparation process of boron-doped silicon carbide, palladium nitrate is also introduced, which can facilitate the formation of well-crystallized boron-doped silicon carbide, help boron atoms be more evenly distributed in silicon carbide, improve its electrical properties, and promote the electrical conductivity of boron-doped silicon carbide. Second, the dispersion uniformity of boron-doped silicon carbide is promoted by introducing modified polyethyleneimine.

[0022] In the solution, the modified polyethyleneimine is obtained by graft modification with nonylphenol polyoxyethylene ether and 3-chloropropyltriethoxysilane. Since the modified polyethyleneimine contains nonylphenol polyoxyethylene ether segments, which belong to non-ionic surfactant segments, compared with directly introducing non-ionic surfactants, it is easier to complex metal ions and promote the embedding of boron-doped silicon carbide in the silver plating layer. At the same time, 3-chloropropyltriethoxysilane is grafted, and it cooperates with the nonylphenol polyoxyethylene ether segments to more easily promote the dispersion of boron-doped silicon carbide. In addition, the modified polyethyleneimine can effectively regulate the reduction rate of silver ions, promote the uniform deposition of silver ions, thereby obtaining a fine and smooth silver plating layer, inhibiting the pores and defects of the silver plating layer, and improving the compactness and corrosion resistance of the silver plating layer. After grafting, due to the nonylphenol polyoxyethylene ether segments, the surface tension can be reduced, which is more conducive to the deposition of silver ions on the surface of the substrate, improving the flatness and the stability of the silver plating layer. And the modified polyethyleneimine can cooperate with 5,5-dimethylhydantoin. First, through the coordination action with silver ions, the modified polyethyleneimine is preferentially adsorbed on the active sites on the silver surface, while 5,5-dimethylhydantoin can fill the gaps in the adsorption layer formed by the modified polyethyleneimine. The two cooperate with each other to improve the integrity and compactness of the protective film, thereby more effectively preventing the contact between the corrosive medium and the silver plating layer, playing a role of synergistic corrosion inhibition and improving the corrosion resistance of the silver plating layer. Second, the two may also have a synergistic effect on the growth of silver grains during the silver plating process. The modified polyethyleneimine can regulate the reduction rate of silver ions, while 5,5-dimethylhydantoin will have a certain interaction with silver ions, changing the growth direction and speed of silver grains. The two work together to make the silver grains finer and more uniform, thereby improving the mechanical properties such as the hardness and wear resistance of the silver plating layer.

[0023] In summary, through the optimization of the pre-plating solution and the silver plating solution, the comprehensive performance of the copper-based profile can be effectively improved. Specific embodiments

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] It should be noted that the following parts are by weight, and there are no special restrictions on the purchasing manufacturers of all raw materials involved in the present invention. Exemplarily, they include: In the following examples, the solvent involved in the preparation of boron-doped silicon carbide is deionized water; the polyethyleneimine is branched polyethyleneimine, with Mn being 10,000 and the brand being Ron; the content of silver nitrate > 99.8%; the content of sodium citrate is 99%; the CAS number of 5,5-dimethylhydantoin is 77-71-4; the CAS number of 2-methyl-4-pyridineboronic acid is 579476-63-4; the effective component of palladium nitrate is 98%; the content of silica sol is 40%; the CAS number of nonylphenol polyoxyethylene ether is 26027-38-3; the CAS number of 3-chloropropyltriethoxysilane is 5089-70-3; the above and other raw materials are all commercially available.

[0026] Example 1: A preparation method of a high thermal conductivity copper-based profiled material for high-voltage electrical appliances, comprising the following steps:

[0027] Preliminary preparation: (1) Under a nitrogen atmosphere, 3.8 parts of nonylphenol polyoxyethylene ether and 1.4 parts of thionyl chloride are sequentially added to 40 parts of chloroform. At 35°C, a 0.1 mol / L sodium hydroxide solution is added dropwise for neutralization, and the mixture is stirred and reacted for 3 hours; polyethyleneimine-chloroform (20 parts of polyethyleneimine, 50 parts of chloroform) and 3-chloropropyltriethoxysilane-chloroform (1.6 parts of 3-chloropropyltriethoxysilane, 10 parts of chloroform) are added; the temperature is raised to 50°C, and the mixture is stirred and reacted for 24 hours, washed and dried to obtain modified polyethyleneimine;

[0028] (2) 15 parts of sucrose, 12 parts of silica sol, 0.36 part of 2-methyl-4-pyridineboronic acid, and 0.25 part of palladium nitrate are sequentially added to the solvent, and hydrothermal reaction is carried out at 180°C for 5 hours, filtered, dried, placed under a nitrogen atmosphere, and reduction reaction is carried out at 1300°C for 12 hours, and then cooled; the product is placed under an air atmosphere, calcined at 750°C for 4 hours, cooled, washed, dried, and ground to obtain boron-doped silicon carbide;

[0029] Step 1: The profiled purple copper bar is alkali-washed in a 10 g / L aqueous sodium hydroxide solution for 15 minutes, washed with water and dried with nitrogen; it is transferred to a 150 mL / L sulfuric acid aqueous solution for pickling for 10 minutes, washed with water and dried with nitrogen; a pretreated copper-based profiled material is obtained;

[0030] Step 2: The pretreated copper-based profiled material is placed in a pre-plating solution, and the process parameters are set as follows: the temperature of the pre-plating solution is 25°C, the current density is 0.4 A / dm 2 2, and pre-plated for 15 seconds; it is transferred to a silver plating solution, and the process parameters are set as follows: the temperature of the silver plating solution is 30°C, the current density is 0.6 A / dm 2, the stirring rate is 600 r / min, and electroplating is carried out for 1.2 hours; then it is washed with water and dried with nitrogen to obtain a high thermal conductivity copper-based profile;

[0031] Among them, the pre-plating solution includes the following components: silver nitrate 0.5 g / L, thiourea 2.2 g / L, sodium citrate 58 g / L, and the solvent is deionized water; the silver plating solution includes the following components: silver nitrate 10 g / L, potassium sodium tartrate 85 g / L, ammonia water 70 mL / L, modified polyethyleneimine 0.6 g / L, 5,5-dimethylhydantoin 1.2 g / L, boron-doped silicon carbide 8.8 g / L, and the solvent is deionized water.

[0032] Example 2: A preparation method of a high thermal conductivity copper-based profile for high-voltage electrical appliances, comprising the following steps:

[0033] Preliminary preparation: (1) Under a nitrogen atmosphere, 3.8 parts of nonylphenol polyoxyethylene ether and 1.4 parts of thionyl chloride are successively added to 40 parts of chloroform. At 35 °C, a 0.1 mol / L sodium hydroxide solution is added dropwise for neutralization, and the stirring reaction is carried out for 3 hours; polyethyleneimine-chloroform (20 parts of polyethyleneimine, 50 parts of chloroform) and 3-chloropropyltriethoxysilane-chloroform (1.6 parts of 3-chloropropyltriethoxysilane, 10 parts of chloroform) are added; the temperature is raised to 50 °C, and the stirring reaction is carried out for 24 hours, followed by washing and drying to obtain modified polyethyleneimine;

[0034] (2) 15 parts of sucrose, 12 parts of silica sol, 0.36 part of 2-methyl-4-pyridineboronic acid, and 0.25 part of palladium nitrate are successively added to the solvent, and hydrothermal reaction is carried out at 180 °C for 5 hours, followed by filtration, drying, placing under a nitrogen atmosphere, and carrying out a reduction reaction at 1300 °C for 12 hours, and then cooling; the product is placed under an air atmosphere and calcined at 750 °C for 4 hours, followed by cooling, washing, drying, and grinding to obtain boron-doped silicon carbide;

[0035] Step 1: The profiled purple copper bar is alkali-washed in an 8 g / L sodium hydroxide aqueous solution for 15 minutes, washed with water and dried with nitrogen; then it is transferred to a 140 mL / L sulfuric acid aqueous solution for pickling for 15 minutes, washed with water and dried with nitrogen; a pretreated copper-based profile is obtained;

[0036] Step 2: The pretreated copper-based profile is placed in the pre-plating solution, and the process parameters are set as follows: the temperature of the pre-plating solution is 30 °C, the current density is 0.2 A / dm 2 , and pre-plating is carried out for 30 seconds; then it is transferred to the silver plating solution, and the process parameters are set as follows: the temperature of the silver plating solution is 20 °C, the current density is 0.8 A / dm 2 , the stirring rate is 600 r / min, and electroplating is carried out for 1 hour; then it is washed with water and dried with nitrogen to obtain a high thermal conductivity copper-based profile;

[0037] Among them, the pre-plating solution includes the following components: silver nitrate 1 g / L, thiourea 3 g / L, sodium citrate 60 g / L, and the solvent is deionized water; the silver plating solution includes the following components: silver nitrate 12 g / L, potassium sodium tartrate 100 g / L, ammonia water 60 mL / L, modified polyethyleneimine 0.5 g / L, 5,5-dimethylhydantoin 1 g / L, boron-doped silicon carbide 8 g / L, and the solvent is deionized water.

[0038] Example 3: A preparation method of a high thermal conductivity copper-based profiled material for high-voltage electrical appliances, comprising the following steps:

[0039] Preliminary preparation: (1) Under a nitrogen atmosphere, 3.8 parts of nonylphenol polyoxyethylene ether and 1.4 parts of thionyl chloride are successively added to 40 parts of chloroform. At 35 °C, a 0.1 mol / L sodium hydroxide solution is added dropwise for neutralization, and the mixture is stirred and reacted for 3 hours; polyethyleneimine-chloroform (20 parts of polyethyleneimine, 50 parts of chloroform) and 3-chloropropyltriethoxysilane-chloroform (1.6 parts of 3-chloropropyltriethoxysilane, 10 parts of chloroform) are added; the temperature is raised to 50 °C, and the mixture is stirred and reacted for 24 hours, washed and dried to obtain modified polyethyleneimine;

[0040] (2) 15 parts of sucrose, 12 parts of silica sol, 0.36 part of 2-methyl-4-pyridineboronic acid, and 0.25 part of palladium nitrate are successively added to the solvent, and hydrothermal reaction is carried out at 180 °C for 5 hours, filtered and dried, placed under a nitrogen atmosphere, and reduction reaction is carried out at 1300 °C for 12 hours, and the temperature is lowered; the product is placed under an air atmosphere and calcined at 750 °C for 4 hours, the temperature is lowered, washed, dried and ground to obtain boron-doped silicon carbide;

[0041] Step 1: The profiled copper bar is placed in a 10 g / L sodium hydroxide aqueous solution for alkali washing for 15 minutes, washed with water and dried with nitrogen; transferred to a 150 mL / L sulfuric acid aqueous solution for acid washing for 10 minutes, washed with water and dried with nitrogen; to obtain a pretreated copper-based profiled material;

[0042] Step 2: The pretreated copper-based profiled material is placed in the pre-plating solution, and the process parameters are set as follows: the temperature of the pre-plating solution is 25 °C, the current density is 0.5 A / dm 2 and pre-plated for 10 seconds; transferred to the silver plating solution, and the process parameters are set as follows: the temperature of the silver plating solution is 30 °C, the current density is 0.5 A / dm 2 the stirring rate is 600 r / min, and electroplating is carried out for 1.5 hours; washed with water and dried with nitrogen to obtain a high thermal conductivity copper-based profiled material;

[0043] Among them, the pre-plating solution includes the following components: silver nitrate 0.5 g / L, thiourea 2 g / L, sodium citrate 50 g / L, and the solvent is deionized water; the silver plating solution includes the following components: silver nitrate 8 g / L, potassium sodium tartrate 80 g / L, ammonia water 80 mL / L, modified polyethyleneimine 1 g / L, 5,5-dimethylhydantoin 1.5 g / L, boron-doped silicon carbide 10 g / L, and the solvent is deionized water.

[0044] Comparative Example 1: The pre-plating process is not set; the rest is the same as in Example 1; the specific process is as follows:

[0045] Preliminary preparation: (1) Under a nitrogen atmosphere, 3.8 parts of nonylphenol polyoxyethylene ether and 1.4 parts of thionyl chloride are successively added to 40 parts of chloroform. At 35 °C, 0.1 mol / L sodium hydroxide solution is added dropwise for neutralization, and the mixture is stirred and reacted for 3 hours; polyethyleneimine-chloroform (20 parts of polyethyleneimine, 50 parts of chloroform) and 3-chloropropyltriethoxysilane-chloroform (1.6 parts of 3-chloropropyltriethoxysilane, 10 parts of chloroform) are added; the temperature is raised to 50 °C, and the mixture is stirred and reacted for 24 hours, washed and dried to obtain modified polyethyleneimine;

[0046] (2) 15 parts of sucrose, 12 parts of silica sol, 0.36 part of 2-methyl-4-pyridineboronic acid, and 0.25 part of palladium nitrate are successively added to the solvent, and hydrothermal reaction is carried out at 180 °C for 5 hours, filtered and dried, placed under a nitrogen atmosphere, and reduction reaction is carried out at 1300 °C for 12 hours, and the temperature is lowered; the product is placed under an air atmosphere and calcined at 750 °C for 4 hours, the temperature is lowered, washed, dried and ground to obtain boron-doped silicon carbide;

[0047] Step 1: The profiled copper bar is placed in a 10 g / L sodium hydroxide aqueous solution for alkali washing for 15 minutes, washed with water and blown dry with nitrogen; transferred to a 150 mL / L sulfuric acid aqueous solution for acid washing for 10 minutes, washed with water and blown dry with nitrogen; the pretreated copper-based profiled material is obtained;

[0048] Step 2: The pretreated copper-based profiled material is placed in the silver plating solution, and the process parameters are set as follows: the temperature of the silver plating solution is 30 °C, the current density is 0.6 A / dm 2 , the stirring rate is 600 r / min, and electroplating is carried out for 1.2 hours; washed with water and blown dry with nitrogen to obtain a highly thermally conductive copper-based profiled material;

[0049] Among them, the silver plating solution includes the following components: silver nitrate 10 g / L, potassium sodium tartrate 85 g / L, ammonia water 70 mL / L, modified polyethyleneimine 0.6 g / L, 5,5-dimethylhydantoin 1.2 g / L, boron-doped silicon carbide 8.8 g / L, and the solvent is deionized water.

[0050] Comparative Example 2: Silicon carbide is used to replace boron-doped silicon carbide in the silver plating solution; the rest is the same as in Example 1; the specific process is as follows:

[0051] Preliminary preparation: (1) Under a nitrogen atmosphere, 3.8 parts of nonylphenol polyoxyethylene ether and 1.4 parts of thionyl chloride were successively added to 40 parts of chloroform. At 35°C, a 0.1 mol / L sodium hydroxide solution was added dropwise for neutralization, and the mixture was stirred and reacted for 3 hours; polyethyleneimine-chloroform (20 parts of polyethyleneimine, 50 parts of chloroform) and 3-chloropropyltriethoxysilane-chloroform (1.6 parts of 3-chloropropyltriethoxysilane, 10 parts of chloroform) were added; the temperature was raised to 50°C, and the mixture was stirred and reacted for 24 hours, washed and dried to obtain modified polyethyleneimine;

[0052] (2) 15 parts of sucrose and 12 parts of silica sol were successively added to the solvent, and hydrothermal reaction was carried out at 180°C for 5 hours. After filtration and drying, it was placed under a nitrogen atmosphere and subjected to a reduction reaction at 1300°C for 12 hours, and then cooled; the product was placed under an air atmosphere and calcined at 750°C for 4 hours, cooled, washed, dried and ground to obtain silicon carbide;

[0053] Step 1: The profiled copper bar was pickled in a 10 g / L sodium hydroxide aqueous solution for 15 minutes, washed with water and dried with nitrogen; transferred to a 150 mL / L sulfuric acid aqueous solution for pickling for 10 minutes, washed with water and dried with nitrogen; the pretreated copper-based profiled material was obtained;

[0054] Step 2: The pretreated copper-based profiled material was placed in the pre-plating solution, and the process parameters were set as follows: the temperature of the pre-plating solution was 25°C, the current density was 0.4 A / dm 2 、pre-plated for 15 seconds; transferred to the silver plating solution, and the process parameters were set as follows: the temperature of the silver plating solution was 30°C, the current density was 0.6 A / dm 2 、the stirring rate was 600 r / min, and electroplating was carried out for 1.2 hours; washed with water and dried with nitrogen to obtain a highly thermally conductive copper-based profiled material;

[0055] Among them, the pre-plating solution includes the following components: silver nitrate 0.5 g / L, thiourea 2.2 g / L, sodium citrate 58 g / L, and the solvent is deionized water; the silver plating solution includes the following components: silver nitrate 10 g / L, potassium sodium tartrate 85 g / L, ammonia water 70 mL / L, modified polyethyleneimine 0.6 g / L, 5,5-dimethylhydantoin 1.2 g / L, silicon carbide 8.8 g / L, and the solvent is deionized water.

[0056] Comparative Example 3: In the silver plating solution, modified polyethyleneimine was replaced with polyethyleneimine; the rest was the same as in Example 1; the specific process was as follows:

[0057] Preliminary preparation: 15 parts of sucrose, 12 parts of silica sol, 0.36 part of 2-methyl-4-pyridineboronic acid, and 0.25 part of palladium nitrate were successively added to a solvent, and hydrothermal reaction was carried out at 180 °C for 5 hours, followed by filtration, drying, placing in a nitrogen atmosphere, and reduction reaction at 1300 °C for 12 hours, then cooling; the product was placed in an air atmosphere, calcined at 750 °C for 4 hours, cooled, washed, dried, and ground to obtain boron-doped silicon carbide;

[0058] Step 1: The profiled copper bar was pickled in a 10 g / L sodium hydroxide aqueous solution for 15 minutes, washed with water, and dried with nitrogen; then transferred to a 150 mL / L sulfuric acid aqueous solution for pickling for 10 minutes, washed with water, and dried with nitrogen; the pretreated copper-based profiled material was obtained;

[0059] Step 2: The pretreated copper-based profiled material was placed in a pre-plating solution, and the process parameters were set as follows: the temperature of the pre-plating solution was 25 °C, the current density was 0.4 A / dm 2 , and pre-plating was carried out for 15 seconds; then transferred to a silver plating solution, and the process parameters were set as follows: the temperature of the silver plating solution was 30 °C, the current density was 0.6 A / dm 2 , the stirring rate was 600 r / min, and electroplating was carried out for 1.2 hours; washed with water and dried with nitrogen to obtain a high-thermal-conductivity copper-based profiled material;

[0060] Among them, the pre-plating solution includes the following components: 0.5 g / L of silver nitrate, 2.2 g / L of thiourea, 58 g / L of sodium citrate, and the solvent is deionized water; the silver plating solution includes the following components: 10 g / L of silver nitrate, 85 g / L of potassium sodium tartrate, 70 mL / L of ammonia water, 0.6 g / L of polyethyleneimine, 1.2 g / L of 5,5-dimethylhydantoin, 8.8 g / L of boron-doped silicon carbide, and the solvent is deionized water.

[0061] Comparative Example 4: The modified polyethyleneimine in the silver plating solution was replaced with a single modified polyethyleneimine; the rest was the same as in Example 1; the specific process was as follows:

[0062] Preliminary preparation: (1) Under a nitrogen atmosphere, 3.8 parts of nonylphenol polyoxyethylene ether and 1.4 parts of thionyl chloride were successively added to 50 parts of chloroform, and at 35 °C, a 0.1 mol / L sodium hydroxide solution was added dropwise for neutralization, and the stirring reaction was carried out for 3 hours; polyethyleneimine-chloroform (20 parts of polyethyleneimine, 50 parts of chloroform) was added; the temperature was raised to 50 °C, and the stirring reaction was carried out for 24 hours, followed by washing and drying to obtain modified polyethyleneimine;

[0063] (2) Add 15 parts of sucrose, 12 parts of silica sol, 0.36 part of 2-methyl-4-pyridineboronic acid, and 0.25 part of palladium nitrate to a solvent in sequence, carry out hydrothermal reaction at 180 °C for 5 hours, filter and dry, place it in a nitrogen atmosphere, carry out reduction reaction at 1300 °C for 12 hours, and cool down; place the product in an air atmosphere, calcine at 750 °C for 4 hours, cool down, wash, dry and grind to obtain boron-doped silicon carbide;

[0064] Step 1: Immerse the profiled copper bar in a 10 g / L sodium hydroxide aqueous solution for alkali washing for 15 minutes, wash with water and blow dry with nitrogen; transfer it to a 150 mL / L sulfuric acid aqueous solution for acid washing for 10 minutes, wash with water and blow dry with nitrogen; obtain the pretreated copper-based profiled material;

[0065] Step 2: Place the pretreated copper-based profiled material in a pre-plating solution, and set the process parameters as follows: the temperature of the pre-plating solution is 25 °C, the current density is 0.4 A / dm 2 、pre-plate for 15 seconds; transfer it to a silver plating solution, and set the process parameters as follows: the temperature of the silver plating solution is 30 °C, the current density is 0.6 A / dm 2 、the stirring rate is 600 r / min, and electroplate for 1.2 hours; wash with water and blow dry with nitrogen to obtain the high thermal conductivity copper-based profiled material;

[0066] Among them, the pre-plating solution includes the following components: silver nitrate 0.5 g / L, thiourea 2.2 g / L, sodium citrate 58 g / L, and the solvent is deionized water; the silver plating solution includes the following components: silver nitrate 10 g / L, potassium sodium tartrate 85 g / L, ammonia water 70 mL / L, modified polyethyleneimine 0.6 g / L, 5,5-dimethylhydantoin 1.2 g / L, boron-doped silicon carbide 8.8 g / L, and the solvent is deionized water.

[0067] Performance test 1: Detect the relevant performances of the high thermal conductivity copper-based profiled materials prepared in the examples and comparative examples at multiple points. (1) Use a metal four-probe tester to detect the resistivity; (2) Use a laser thermal conductivity meter to test the thermal diffusivity and specific heat capacity of the composite material, and calculate the thermal conductivity; (3) Use an ultrasonic flaw detector to detect it to judge whether there are defects such as internal cracks, pores, and inclusions, and calculate the yield rate. The obtained data are shown in the following table:

[0068]

[0069]

[0070] Conclusion: It can be seen from the data in the above table that in this application, pre-plating is used to improve the uniformity of subsequent plating of copper-based profiles; at the same time, by introducing boron-doped silicon carbide, while effectively enhancing the thermal conductivity, the increase in resistance is inhibited to ensure the electrical conductivity of the high-thermal-conductivity copper-based profiles. Comparative Example 1 shows the importance of the pre-plating layer; Comparative Examples 2-4 show the importance of defining boron-doped silicon carbide and modified polyethyleneimine, and the relevant linearity has different degrees of influence on the comprehensive performance.

[0071] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a high thermal conductivity copper-based profile for high-voltage electrical appliances, characterized in that: The following steps are involved: Step 1: Alkaline washing and acid washing are performed on the copper-based profile in sequence to obtain a pretreated copper-based profile; Step 2: placing the pretreated copper-based profile in a pre-plating solution for pre-plating; The product is transferred to a silver plating solution for electroplating to obtain a high thermal conductivity copper-based profile.

2. The method for preparing a high thermal conductivity copper-based profile for high voltage electrical appliances according to claim 1, characterized in that: The alkali solution for alkali washing is 8-10 g / L sodium hydroxide aqueous solution, and the alkali washing time is 10-30 minutes; the acid solution for acid washing is 140-150 mL / L sulfuric acid aqueous solution, and the acid washing time is 10-30 minutes.

3. The method for preparing a high thermal conductivity copper-based profile for high voltage electrical appliances according to claim 1, characterized in that: The pre-plating solution includes the following components: 0.5-1 g / L silver nitrate, 2-3 g / L thiourea, 50-60 g / L sodium citrate, and the solvent is deionized water; the pre-plating process parameters are: temperature of 10-35°C, current density of 0.2-0.5 A / dm 2 , the electroplating time is 10 to 30 seconds.

4. The method for preparing a high thermal conductivity copper-based profile for high voltage electrical appliances according to claim 1, characterized in that: The silver plating solution comprises the following components: 8-12 g / L of silver nitrate, 80-100 g / L of potassium sodium tartrate, 60-80 mL / L of ammonia water, 0.5-1 g / L of modified polyethyleneimine, 1-1.5 g / L of 5,5-dimethylhydantoin, and 8-10 g / L of boron-doped silicon carbide, and the solvent is deionized water.

5. The method for preparing a high thermal conductivity copper-based profile for high voltage electrical appliances according to claim 4, characterized in that: The electroplating process parameters are: temperature of 20-30°C, current density of 0.5-0.8A / dm 2 , the electroplating time is 1 to 1.5 hours, and the stirring rate is 600 to 700 r / min.

6. The method for preparing a high thermal conductivity copper-based profile for high voltage electrical appliances according to claim 4, characterized in that: The preparation method of the modified polyethyleneimine comprises: adding nonylphenol polyoxyethylene ether and thionyl chloride to chloroform in sequence under a nitrogen atmosphere, adding dropwise 0.06-0.1 mol / L sodium hydroxide solution at 30-40° C. for neutralization, and stirring for reaction for 2-3 hours; adding polyethyleneimine-chloroform and 3-chloropropyltriethoxysilane-chloroform; heating to 45-55° C., stirring for reaction for 24 hours, washing and drying to obtain the modified polyethyleneimine.

7. The method for preparing a high thermal conductivity copper-based profile for high voltage electrical appliances according to claim 6, characterized in that: The modified polyethyleneimine comprises the following raw materials: 20 parts of polyethyleneimine, 3-4 parts of nonylphenol polyoxyethylene ether, 1.2-1.5 parts of thionyl chloride, and 1-2 parts of 3-chloropropyltriethoxysilane.

8. The method for preparing a high thermal conductivity copper-based profile for high voltage electrical appliances according to claim 4, characterized in that: The preparation method of the boron-doped silicon carbide is as follows: sucrose, silica sol, 2-methyl-4-pyridineboric acid and palladium nitrate are sequentially added to a solvent, hydrothermally reacted at 150-200° C. for 5-6 hours, filtered and dried, placed in a nitrogen atmosphere, reduced at 1000-1500° C. for 10-12 hours, and cooled; the product is placed in an air atmosphere, calcined at 500-800° C. for 3-6 hours, cooled, washed and dried to obtain boron-doped silicon carbide.

9. The method for preparing a high thermal conductivity copper-based profile for high voltage electrical appliances according to claim 8, characterized in that: In the raw materials of the boron-doped silicon carbide, the mass ratio of sucrose, silica sol, 2-methyl-4-pyridineboric acid and palladium nitrate is 15:(10-12):(0.2-0.5):(0.2-0.3).

10. A high thermal conductivity copper-based special-shaped material prepared according to the method for preparing a high thermal conductivity copper-based special-shaped material for high-voltage electrical appliances according to any one of claims 1 to 9.

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