Corrosion-resistant copper slot wire and electrochemical corrosion prevention process thereof

Abstract

The application discloses a kind of corrosion-resistant copper slot wire and its anti-electrochemical corrosion process, it is related to copper slot wire technical field, from copper matrix outwardly in turn is nanocrystalline transition layer and surface protective layer;The copper matrix is by mass percentage, composition includes:Ag 0.1-0.3%, rare earth element 0.01-0.03%, Ga 0.01-0.03%, Mn 0.1-0.3%, Si 0.05-0.15%, Ni 0.2-0.4%, Zr 0.03-0.06%, Ti 0.05-0.1%, Cr 0.3-0.5%, B 0.001-0.003%, the balance is Cu and other inevitable impurities.The slot wire corrosion resistance, fatigue resistance and electrical conductivity are excellent, and the service life is long.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of copper slot wire, in particular to a corrosion-resistant copper slot wire and an electrochemical corrosion prevention process thereof. BACKGROUND

[0002] In the long-term operation process of electronic equipment, copper slot wire as an important conductive component often faces complex use environment. At present, the traditional copper slot wire is prone to electrochemical corrosion in humid, electrolyte solution-containing and other environments, which will cause the conductive performance of the copper slot wire to decrease, and even cause problems such as fracture, seriously affecting the normal operation and service life of the electronic equipment. Therefore, it is particularly important to develop a corrosion-resistant copper slot wire.

[0003] The traditional copper slot wire improves corrosion resistance through plating or alloying, but a single plating layer such as a nickel plating layer is prone to form a micro-battery in a Cl - environment to accelerate corrosion. Inadequate optimization of copper alloy components will lead to uneven passivation film. In addition, some processes require high-temperature treatment or complex equipment, making it difficult to mass-produce. At present, there are products on the market that achieve corrosion resistance by coating a protective coating on the surface of the copper slot wire. However, these protective coatings are prone to fall off and age during long-term use, greatly reducing the corrosion prevention effect. Moreover, the traditional coating preparation process is complex and has high production costs, which is not conducive to large-scale production and application.

[0004] In order to solve the above problems, a new type of corrosion-resistant boron copper alloy is disclosed in Chinese patent CN103131887B, which contains 37-39% zinc, 0.5-1.5% tin, 0.5-1.0% aluminum, 0.03-0.05% bismuth, 0.005-0.01% boron, 0.4-1.0% iron, 0.01-0.03% selenium, 0.02-0.03% cobalt and the balance of copper by weight percentage. The corrosion-resistant boron copper alloy has similar physical properties to existing nickel-copper or zinc-copper alloys, higher corrosion resistance than existing nickel-copper or zinc-copper alloys, and lower cost. However, its electrochemical corrosion prevention performance, fatigue resistance and conductivity still need to be further improved.

[0005] Therefore, it is necessary to develop a corrosion-resistant copper slot wire with excellent corrosion resistance, fatigue resistance and conductivity, long service life and an electrochemical corrosion prevention process thereof, which meets market demand, has wide market value and application prospect, and has very important significance for promoting the development of the copper slot wire field. SUMMARY

[0006] The present application aims to overcome the shortcomings of the prior art and provide a corrosion-resistant copper slot wire with excellent corrosion resistance, fatigue resistance and conductivity, long service life and an electrochemical corrosion prevention process thereof.

[0007] To achieve the above object, the technical scheme adopted by the present application is: a corrosion-resistant copper slot wire, from the copper base outward, is a nanocrystalline transition layer and a surface protection layer; the copper base, by mass percentage, comprises: Ag 0.1-0.3%, rare earth elements 0.01-0.03%, Ga 0.01-0.03%, Mn 0.1-0.3%, Si 0.05-0.15%, Ni 0.2-0.4%, Zr 0.03-0.06%, Ti 0.05-0.1%, Cr 0.3-0.5%, B 0.001-0.003%, and the balance is Cu and other unavoidable impurities.

[0008] Preferably, the rare earth elements are Ce, Nd, and Pr mixed in a mass ratio of 2: (1-2): (0.8-1.2).

[0009] Preferably, the thickness of the nanocrystalline transition layer is 5-8 μm.

[0010] Preferably, the thickness of the surface protection layer is 10-15 μm.

[0011] Another object of the present application is to provide an electrochemical corrosion prevention process for the corrosion-resistant copper slot wire, comprising the following steps:

[0012] Step S1, surface pretreatment of the copper base: using 400# sandpaper to polish the copper base to a surface roughness Ra≤1.0 μm, removing the oxide layer; then sequentially performing stage cleaning and polishing to obtain the pretreated copper base;

[0013] Step S2, formation of the nanocrystalline transition layer: using pulse plating to prepare the nanocrystalline transition layer on the surface of the copper base;

[0014] Step S2, preparation of the surface protection layer: uniformly dispersing graphene oxide, hydroxyapatite, and nanometer titanium dioxide in epoxy resin, adding an appropriate amount of curing agent, stirring uniformly, and then using a spraying method to coat it on the surface of the transition layer, and curing at a temperature of 118-122 ℃ for 2-3 hours to form the surface protection layer.

[0015] Preferably, the stage cleaning specifically comprises: first, ultrasonic cleaning with acetone for 10-15 min, then rinsing with deionized water, then acid pickling for 3-5 min, and finally rinsing with deionized water and drying.

[0016] Preferably, the acid used for acid pickling is a 1-3% sulfuric acid solution, and the acid pickling temperature is 35-40 ℃.

[0017] Preferably, the pulse parameters of the pulse electroplating are as follows: positive current density 11-13 A / dm2, reverse current density 2-4 A / dm2, pulse frequency 1000 Hz, duty cycle 60%, temperature 53-57℃, and deposition time 28-32 min.

[0018] Preferably, the electroplating solution of the pulse electroplating comprises the following components: nickel sulfate 20-30 g / L, sodium hypophosphite 15-20 g / L, sodium citrate 10-15 g / L, cerium nitrate 3-5 g / L, zwitterionic salt 0.1-0.3 g / L, adenosine 0.1-0.5 g / L, and 2,2'-biquinoline-4,4'-dicarboxylic acid disodium 0.05-0.1 g / L, and the pH is adjusted to 4.8-5.5 by sulfuric acid.

[0019] Preferably, the zwitterionic salt is 1-benzylpyridine-3-carboxylate.

[0020] Preferably, the mass ratio of the graphene oxide, hydroxyapatite, nanometer titanium dioxide, epoxy resin, and curing agent in step S2 is (3-5):(1-3):(4-6):(85-90):(4-6).

[0021] Preferably, the graphene oxide is single-layer graphene oxide, the flake diameter is 0.5-5 μm, and the thickness is 0.8-1.2 nm.

[0022] Preferably, the average diameter of the hydroxyapatite is 1-5 μm, and the average particle size of the nanometer titanium dioxide is 10-80 nm.

[0023] Preferably, the epoxy resin is E-51 epoxy resin.

[0024] Preferably, the curing agent is 3,3'-diamino-4,4'-difluorodiphenyl sulfone.

[0025] Due to the use of the above technical solution, the present application has the following beneficial effects:

[0026] (1) The anti-electrochemical corrosion process for the corrosion-resistant copper slot wire is simple, easy to operate, convenient to control, high in efficiency and product qualification rate, suitable for continuous large-scale production, and has high popularization and application value.

[0027] (2) The corrosion-resistant copper slot wire disclosed by the application comprises, from the copper base outward, a nanocrystalline transition layer and a surface protective layer; the copper base comprises, by mass percentage, Ag 0.1-0.3%, rare earth elements 0.01-0.03%, Ga 0.01-0.03%, Mn 0.1-0.3%, Si 0.05-0.15%, Ni 0.2-0.4%, Zr 0.03-0.06%, Ti 0.05-0.1%, Cr 0.3-0.5%, B 0.001-0.003%, and the balance of Cu and other unavoidable impurities. Through the mutual cooperation of the components, the corrosion resistance and fatigue resistance are effectively improved without significantly reducing the electrical conductivity, thereby effectively prolonging the service life of the copper slot wire. The rare earth elements are Ce, Nd and Pr mixed in a mass ratio of 2: (1-2): (0.8-1.2); through the addition of the rare earth elements with such a composition and the cooperation with other components, high-melting-point compounds are formed with impurities such as oxygen and sulfur, the distortion of the crystal lattice by impurities is reduced, and the electrical conductivity is indirectly improved; meanwhile, the rare earth elements inhibit grain growth by forming a dispersed phase, thereby improving the strength of the material while having little effect on the electrical conductivity; in addition, the rare earth elements can be adsorbed at the grain boundaries, inhibit the segregation of impurities at the grain boundaries, reduce the tendency of intergranular corrosion, and improve the corrosion resistance of the material.

[0028] (3) The corrosion-resistant copper slot wire disclosed by the application comprises, from the copper base outward, a nanocrystalline transition layer and a surface protective layer; through such a structural design, the copper base can be protected by “physical + chemical” double protection, which not only blocks the penetration of Cl - , but also effectively inhibits electrochemical reactions. The transition layer has good corrosion resistance and bonding force with the copper base, which can effectively prevent the direct contact of the copper base with the external corrosive medium. The surface protective layer has excellent barrier properties, and the sheet structure of graphene oxide can form a multi-layer barrier in the coating, hindering the penetration of corrosive media. The three-dimensional network structure formed by hydroxyapatite and graphene oxide. The nano-titanium dioxide coating has photocatalytic properties and can generate active substances such as hydroxyl radicals under light conditions, which can decompose organic pollutants and part of inorganic corrosive media adsorbed on the surface of the coating, further improving the corrosion resistance. At the same time, the nano-titanium dioxide coating also has good chemical stability and weather resistance, which can maintain its protective performance during long-term use. The design of such a multi-layer structure not only improves the corrosion resistance of the copper slot wire, but also ensures its good electrical conductivity and mechanical properties, meeting the use requirements of electronic devices in various complex environments. The epoxy resin provides good adhesion and mechanical properties, enabling the surface protective layer to be firmly attached to the surface of the transition layer. The curing agent is 3,3'-diamino-4,4'-difluorodiphenyl sulfone; through curing, a fluorine-containing phenyl sulfone structure is introduced into the protective layer, further improving its corrosion resistance and prolonging its service life.

[0029] (4) The corrosion-resistant copper slot wire disclosed in the application adopts pulse electroplating to prepare a nanocrystalline transition layer on the surface of a copper base, and the pulse electroplating effectively inhibits the continuous growth of crystal grains through periodic current on-off, thereby improving corrosion resistance; the reverse current of the pulse electroplating has an 'etching-activation' effect, so that the interface bonding force is enhanced and the anti-peeling performance is improved; the pulse electroplating releases deposition stress through the reverse current, so that the internal stress of the plating layer is converted into compressive stress, thereby improving the toughness of the plating layer; the electroplating solution of the pulse electroplating comprises the following components with the following concentrations: nickel sulfate 20-30 g / L, sodium hypophosphite 15-20 g / L, sodium citrate 10-15 g / L, cerium nitrate 3-5 g / L, zwitterion salt 0.1-0.3 g / L, adenosine 0.1-0.5 g / L, and 2,2'-biquinoline-4,4'-dicarboxylic acid disodium 0.05-0.1 g / L. The cerium nitrate introduced in the formula is used as a rare earth element additive, which can be adsorbed at the grain boundary of the nickel-phosphorus alloy during the electroplating process, and the grain growth is inhibited through the 'poisoning effect'. The complex system of adenosine, cerium nitrate and 2,2'-biquinoline can simultaneously realize grain refinement, stress regulation and interface strengthening, reduce the porosity of the plating layer, form a dense structure, and further improve the corrosion resistance of the plating layer.

[0030] (5) The corrosion-resistant copper slot wire disclosed in the application has better corrosion resistance and longer service life through reasonable selection of electrochemical corrosion prevention process parameters. DETAILED DESCRIPTION

[0031] The following description is used to disclose the application so that those skilled in the art can implement the application. The preferred embodiments in the following description are only used as examples, and other obvious modifications can be thought of by those skilled in the art. Example 1

[0032] A corrosion-resistant copper slot wire, from the outside of a copper base, is a nanocrystalline transition layer and a surface protective layer; the composition of the copper base includes, by mass percentage: Ag 0.1%, rare earth elements 0.01%, Ga 0.01%, Mn 0.1%, Si 0.05%, Ni 0.2%, Zr 0.03%, Ti 0.05%, Cr 0.3%, B 0.001%, and the balance is Cu and other unavoidable impurities; the rare earth elements are a mixture of Ce, Nd and Pr with a mass ratio of 2:1:0.8; the thickness of the nanocrystalline transition layer is 5 μm; the thickness of the surface protective layer is 10 μm.

[0033] A process for preventing electrochemical corrosion of the corrosion-resistant copper slot wire, comprising the following steps:

[0034] Step S1, copper matrix surface pretreatment: the copper matrix is polished to a surface roughness Ra≤1.0 μm using 400# sandpaper to remove the oxide layer; then stage cleaning and polishing are sequentially performed to obtain the pretreated copper matrix;

[0035] Step S2, formation of a nanocrystalline transition layer: a nanocrystalline transition layer is prepared on the surface of the copper matrix by pulse plating;

[0036] Step S2, preparation of a surface protective layer: graphene oxide, hydroxyapatite, and nanometer titanium dioxide are uniformly dispersed in epoxy resin, an appropriate amount of curing agent is added, and after stirring, the mixture is coated on the surface of the transition layer by spraying and cured at a temperature of 118℃ for 2 hours to form a surface protective layer.

[0037] The stage cleaning is specifically: first, ultrasonic cleaning with acetone for 10 min, then rinsing with deionized water, then acid washing for 3 min, and finally rinsing with deionized water and drying; the acid used for acid washing is a 1% sulfuric acid solution, and the acid washing temperature is 35℃.

[0038] The pulse plating parameters are: forward current density 11 A / dm², reverse current density 2 A / dm², pulse frequency 1000 Hz, duty cycle 60%, temperature 53℃, and deposition time 28 min; the plating solution for pulse plating includes the following components at the following concentrations: nickel sulfate 20 g / L, sodium hypophosphite 15 g / L, sodium citrate 10 g / L, cerium nitrate 3 g / L, zwitterionic salt 0.1 g / L, adenosine 0.1-0.5 g / L, 2,2'-biquinoline-4,4'-dicarboxylic acid disodium 0.05-0.1 g / L, and sulfuric acid is used to adjust the pH to 4.8; the zwitterionic salt is 1-benzylpyridine-3-carboxylate.

[0039] In step S2, the mass ratio of graphene oxide, hydroxyapatite, nanometer titanium dioxide, epoxy resin, and curing agent is 3:1:4:85:4-6; the graphene oxide is single-layer graphene oxide with a flake diameter of 0.5-5 μm and a thickness of 0.8-1.2 nm; the average diameter of the hydroxyapatite is 1 μm; the average particle size of the nanometer titanium dioxide is 10 nm; the epoxy resin is E-51 epoxy resin; and the curing agent is 3,3'-diamino-4,4'-difluorodiphenyl sulfone. Example 2

[0040] A kind of corrosion-resistant copper slot wire, from copper matrix outwardly in turn is nanocrystalline transition layer and surface protection layer;The copper matrix includes the following components by mass percentage: Ag 0.15%, rare earth element 0.015%, Ga 0.015%, Mn 0.15%, Si 0.07%, Ni 0.25%, Zr 0.04%, Ti 0.06%, Cr 0.35%, B 0.0015%, the balance is Cu and other inevitable impurities;The rare earth element is Ce, Nd, Pr mixed by mass ratio 2:1.2:0.9;The thickness of the nanocrystalline transition layer is 5 μm;The thickness of the surface protection layer is 10 μm.

[0041] A kind of electrochemical corrosion prevention process of the corrosion-resistant copper slot wire, comprising the following steps:

[0042] Step S1, copper matrix surface pretreatment: the copper matrix is polished to surface roughness Ra≤1.0 μm using 400# sandpaper, and the oxide layer is removed;Then stage cleaning, polishing are sequentially carried out, to obtain the pretreated copper matrix;

[0043] Step S2, formation of nanocrystalline transition layer: a nanocrystalline transition layer is prepared on the surface of the copper matrix by pulse plating;

[0044] Step S2, preparation of surface protection layer: graphene oxide, hydroxyapatite and nanometer titanium dioxide are uniformly dispersed in epoxy resin, an appropriate amount of curing agent is added, and after stirring uniformly, it is coated on the surface of the transition layer by spraying, and is cured at a temperature of 119 ℃ for 2.3 hours to form a surface protection layer.

[0045] The stage cleaning is specifically: first ultrasonic cleaning with acetone for 11 min, then rinse with deionized water, then acid washing for 3.5 min, and finally rinse with deionized water and dry;The acid used for acid washing is a 1.5% sulfuric acid solution, and the acid washing temperature is 36℃.

[0046] The pulse parameters of the pulse plating are: forward current density 11.5 A / dm², reverse current density 2.5 A / dm², pulse frequency 1000 Hz, duty cycle 60%, temperature 54℃, deposition time 29 min;The plating solution of the pulse plating includes the following components with the following concentrations: nickel sulfate 23 g / L, sodium hypophosphite 17 g / L, sodium citrate 12 g / L, cerium nitrate 3.5 g / L, zwitterionic salt 0.15 g / L, adenosine 0.2 g / L, 2,2'-biquinoline-4,4'-dicarboxylic acid disodium 0.06 g / L, and the PH is adjusted to 4.9 with sulfuric acid;The zwitterionic salt is 1-benzylpyridine-3-carboxylate.

[0047] The mass ratio of the graphene oxide, hydroxyapatite, nanometer titanium dioxide, epoxy resin and curing agent in step S2 is 3.5:1.5:4.5:86:4.5; the graphene oxide is single-layer graphene oxide with a flake diameter of 0.5-5 μm and a thickness of 0.8-1.2 nm; the average diameter of the hydroxyapatite is 2 μm; the average particle size of the nanometer titanium dioxide is 30 nm; the epoxy resin is E-51 epoxy resin; and the curing agent is 3,3'-diamino-4,4'-difluorodiphenyl sulfone. Embodiment 3

[0048] A corrosion-resistant copper slot wire, which comprises, from the copper substrate outward, a nanocrystalline transition layer and a surface protection layer; the copper substrate comprises, by mass percentage, Ag 0.2%, rare earth elements 0.02%, Ga 0.02%, Mn 0.2%, Si 0.1%, Ni 0.3%, Zr 0.045%, Ti 0.07%, Cr 0.4%, B 0.002%, and the balance being Cu and other unavoidable impurities; the rare earth elements are a mixture of Ce, Nd and Pr in a mass ratio of 2:1.5:1; the thickness of the nanocrystalline transition layer is 5 μm; and the thickness of the surface protection layer is 10 μm.

[0049] A process for preventing electrochemical corrosion of the corrosion-resistant copper slot wire, comprising the following steps:

[0050] Step S1, surface pretreatment of the copper substrate: the copper substrate is polished to a surface roughness Ra≤1.0 μm using 400# sandpaper to remove the oxide layer; then stage cleaning and polishing are sequentially performed to obtain the pretreated copper substrate;

[0051] Step S2, formation of the nanocrystalline transition layer: a nanocrystalline transition layer is prepared on the surface of the copper substrate by pulse plating;

[0052] Step S2, preparation of the surface protection layer: graphene oxide, hydroxyapatite and nanometer titanium dioxide are uniformly dispersed in epoxy resin, an appropriate amount of curing agent is added, and after stirring, the mixture is coated on the surface of the transition layer by spraying, and the surface protection layer is formed by curing at a temperature of 120℃ for 2.5 hours.

[0053] The stage cleaning specifically comprises the following steps: first, ultrasonic cleaning with acetone for 13 min, then rinsing with deionized water, then acid pickling for 4 min, and finally rinsing with deionized water and drying; the acid used for acid pickling is a 2% sulfuric acid solution, and the acid pickling temperature is 38℃.

[0054] The pulse parameters of the pulse electroplating are: positive current density 12 A / dm2, reverse current density 3 A / dm2, pulse frequency 1000 Hz, duty cycle 60%, temperature 55°C, and deposition time 30 min; the electroplating solution for the pulse electroplating comprises the following components at the following concentrations: nickel sulfate 25 g / L, sodium hypophosphite 18 g / L, sodium citrate 13 g / L, cerium nitrate 4 g / L, zwitterionic salt 0.2 g / L, adenosine 0.3 g / L, 2,2'-biquinoline-4,4'-dicarboxylic acid disodium 0.07 g / L, and sulfuric acid is used to adjust the pH to 5; the zwitterionic salt is 1-benzylpyridine-3-carboxylate; the mass ratio of the graphene oxide, hydroxyapatite, nanometer titanium dioxide, epoxy resin, and curing agent in step S2 is 4:2:5:88:5; the graphene oxide is single-layer graphene oxide with a flake diameter of 0.5-5 μm and a thickness of 0.8-1.2 nm; the average diameter of the hydroxyapatite is 3 μm; the average particle size of the nanometer titanium dioxide is 60 nm; the epoxy resin is E-51 epoxy resin; and the curing agent is 3,3'-diamino-4,4'-difluorodiphenyl sulfone. Example 4

[0055] A corrosion-resistant copper slot wire, which comprises, from the copper substrate outward, a nanocrystalline transition layer and a surface protection layer; the copper substrate comprises, by mass percentage, Ag 0.25%, rare earth elements 0.025%, Ga 0.025%, Mn 0.25%, Si 0.13%, Ni 0.35%, Zr 0.055%, Ti 0.09%, Cr 0.45%, B 0.0025%, and the balance being Cu and other unavoidable impurities; the rare earth elements are a mixture of Ce, Nd, and Pr at a mass ratio of 2:1.8:1.1; the thickness of the nanocrystalline transition layer is 5 μm; and the thickness of the surface protection layer is 10 μm.

[0056] A process for preventing electrochemical corrosion of the corrosion-resistant copper slot wire, which comprises the following steps:

[0057] Step S1, surface pretreatment of the copper substrate: the copper substrate is polished to a surface roughness Ra≤1.0 μm using 400# sandpaper to remove the oxide layer; then stage cleaning and polishing are sequentially performed to obtain a pretreated copper substrate;

[0058] Step S2, formation of the nanocrystalline transition layer: a nanocrystalline transition layer is prepared on the surface of the copper substrate by pulse electroplating;

[0059] Step S2, preparation of the surface protection layer: graphene oxide, hydroxyapatite, and nanometer titanium dioxide are uniformly dispersed in epoxy resin, an appropriate amount of curing agent is added, and the mixture is stirred uniformly; then the mixture is coated on the surface of the transition layer by spraying, and the coating is cured at a temperature of 121°C for 2.8 hours to form a surface protection layer.

[0060] The stage cleaning is specifically: first ultrasonic cleaning with acetone for 14 min, then rinsing with deionized water, then pickling for 4.5 min, and finally rinsing with deionized water and drying; the acid used in pickling is a 2.5% sulfuric acid solution, and the pickling temperature is 39℃; the pulse parameters of the pulse plating are: forward current density 12.5 A / dm², reverse current density 3.5 A / dm², pulse frequency 1000 Hz, duty cycle 60%, temperature 56℃, and deposition time 31 min.

[0061] The plating solution for the pulse plating includes components with the following concentrations: nickel sulfate 28 g / L, sodium hypophosphite 19 g / L, sodium citrate 14 g / L, cerium nitrate 4.5 g / L, zwitterionic salt 0.25 g / L, adenosine 0.4 g / L, 2,2'-biquinoline-4,4'-dicarboxylic acid disodium 0.09 g / L, and sulfuric acid is used to adjust the pH to 5.3; the zwitterionic salt is 1-benzylpyridine-3-carboxylate; the mass ratio of graphene oxide, hydroxyapatite, nano titanium dioxide, epoxy resin, and curing agent in step S2 is 4.5:2.5:5.5:89:5.5; the graphene oxide is single-layer graphene oxide with a flake diameter of 0.5-5 μm and a thickness of 0.8-1.2 nm; the average diameter of the hydroxyapatite is 4 μm; the average particle size of the nano titanium dioxide is 70 nm; the epoxy resin is E-51 epoxy resin; and the curing agent is 3,3'-diamino-4,4'-difluorodiphenyl sulfone. Example 5

[0062] A corrosion-resistant copper slot wire, from the copper base outward, is a nanocrystalline transition layer and a surface protection layer; the copper base includes, by mass percentage: Ag 0.3%, rare earth elements 0.03%, Ga 0.03%, Mn 0.3%, Si 0.15%, Ni 0.4%, Zr 0.06%, Ti 0.1%, Cr 0.5%, B 0.003%, and the balance is Cu and other unavoidable impurities; the rare earth elements are a mixture of Ce, Nd, and Pr in a mass ratio of 2:2:1.2; the thickness of the nanocrystalline transition layer is 5 μm; and the thickness of the surface protection layer is 10 μm.

[0063] A process for preventing electrochemical corrosion of the corrosion-resistant copper slot wire, including the following steps:

[0064] Step S1, copper base surface pretreatment: using 400# sandpaper to polish the copper base to a surface roughness Ra≤1.0 μm, removing the oxide layer; then sequentially performing stage cleaning and polishing to obtain a pretreated copper base;

[0065] Step S2, formation of the nanocrystalline transition layer: a nanocrystalline transition layer is prepared on the surface of the copper substrate by pulse plating;

[0066] Step S2, preparation of the surface protective layer: graphene oxide, hydroxyapatite and nanometer titanium dioxide are uniformly dispersed in epoxy resin, an appropriate amount of curing agent is added, and after uniform stirring, the surface protective layer is formed on the surface of the transition layer by spraying and curing at a temperature of 122 DEG C for 3 hours.

[0067] The stage cleaning is specifically: first, ultrasonic cleaning with acetone for 15 min, then rinsing with deionized water, then pickling for 5 min, and finally rinsing with deionized water and drying; the acid used in pickling is a 3% sulfuric acid solution, and the pickling temperature is 40 DEG C.

[0068] The pulse parameters of the pulse plating are: forward current density 13 A / dm2, reverse current density 4 A / dm2, pulse frequency 1000 Hz, duty cycle 60%, temperature 57 DEG C, and deposition time 32 min; the plating solution for pulse plating comprises the following components at the following concentrations: nickel sulfate 30 g / L, sodium hypophosphite 20 g / L, sodium citrate 15 g / L, cerium nitrate 5 g / L, zwitterionic salt 0.3 g / L, adenosine 0.5 g / L, 2,2'-biquinoline-4,4'-dicarboxylic acid disodium 0.1 g / L, and sulfuric acid is used to adjust the pH to 5.5; the zwitterionic salt is 1-benzylpyridine-3-carboxylate; the mass ratio of graphene oxide, hydroxyapatite, nanometer titanium dioxide, epoxy resin and curing agent in step S2 is 5:3:6:90:6; the graphene oxide is single-layer graphene oxide with a sheet diameter of 0.5-5 μm and a thickness of 0.8-1.2 nm; the average diameter of the hydroxyapatite is 5 μm; the average particle size of the nanometer titanium dioxide is 80 nm; the epoxy resin is E-51 epoxy resin; and the curing agent is 3,3'-diamino-4,4'-difluorodiphenyl sulfone.

[0069] Comparative Example 1

[0070] This example provides a corrosion-resistant copper slot wire and an electrochemical corrosion prevention process thereof, which are basically the same as those of Example 1, except that Ga, Si and 2,2'-biquinoline-4,4'-dicarboxylic acid disodium are not added.

[0071] Comparative Example 2

[0072] This example provides a corrosion-resistant copper slot wire and an electrochemical corrosion prevention process thereof, which are basically the same as those of Example 1, except that Nd, Zr and adenosine are not added.

[0073] Comparative Example 3

[0074] The example provides a kind of corrosion-resistant copper slot wire and its anti-electrochemical corrosion process, which is basically same with embodiment 1, except that no hydroxyapatite, B and zwitterionic salt are added.

[0075] In order to further illustrate the beneficial technical effects of the corrosion-resistant copper slot wire involved in each embodiment of the present application, the relevant performance tests of the corrosion-resistant copper slot wire involved in each example are carried out, and the test results are shown in Table 1, and the test methods are as follows:

[0076] (1) Conductive performance test: refer to GB / T 351-2019 for testing;

[0077] (2) Corrosion resistance test: refer to GB / T 10125-2021 for neutral salt spray test (5% NaCl solution, 35℃, continuous spraying for 1200 hours, spraying amount is 2mL / 80cm²·h), and observe the corrosion of the sample surface.

[0078] (3) Electrochemical impedance: refer to GB / T 24196-2009 "Metal and alloy electrochemical impedance spectroscopy test method", test in 3.5% NaCl solution (25℃) by three electrode system, working electrode is copper slot wire of each embodiment of the present application (exposed area is 1cm²), reference electrode is saturated calomel electrode (SCE), auxiliary electrode is platinum electrode (area is 5cm²), frequency range is 10²-10 6 Hz.

[0079] (4) Fatigue life: refer to the fatigue test of JISZ 2273-1978, count the number of repetitions until the test piece reaches the breaking point when the load stress is 500MPa; the wire diameter of the test piece is 0.5mm; three test pieces are used for the above test in each example, and the average value of the number of repetitions until the slot wire breaks is calculated.

[0080] As can be seen from Table 1, the corrosion-resistant copper slot wire involved in each embodiment of the present application has more excellent conductivity, fatigue resistance and corrosion resistance than the comparative product, and the combined addition of Ga, Si, 2,2'-biquinoline-4,4'-dicarboxylic acid disodium, Nd, Zr, adenosine, hydroxyapatite, B and zwitterionic salt is beneficial to improving the above properties.

[0081] Table 1 Performance test results of corrosion-resistant copper slot wire

[0082]

[0083] The above examples are only for illustrating the technical concept and characteristics of the present application, the purpose is to enable those skilled in the art to understand the content of the present application and to implement it, and cannot limit the protection scope of the present application, any equivalent changes or modifications made according to the spirit and essence of the present application should be covered within the protection scope of the present application.

Claims

1. An electrochemical corrosion prevention process for corrosion resistant copper slot wire, characterized by, It comprises the following steps: Step S1, surface pretreatment of copper matrix: the copper matrix is polished to a surface roughness Ra≤1.0 μm by using 400# sandpaper to remove the oxide layer; then stage cleaning and polishing are sequentially performed to obtain the pretreated copper matrix; Step S2, formation of nanocrystalline transition layer: a nanocrystalline transition layer is prepared on the surface of the copper matrix by pulse plating; Step S3, preparation of surface protective layer: graphene oxide, hydroxyapatite and nanometer titanium dioxide are uniformly dispersed in epoxy resin, an appropriate amount of curing agent is added, and after uniform stirring, the surface protective layer is formed on the surface of the transition layer by spraying and curing at a temperature of 118-122 ℃ for 2-3 hours; The corrosion-resistant copper slot line comprises, from the copper matrix outward, a nanocrystalline transition layer and a surface protective layer; the copper matrix comprises, by mass percentage, Ag 0.1-0.3%, rare earth elements 0.01-0.03%, Ga 0.01-0.03%, Mn 0.1-0.3%, Si 0.05-0.15%, Ni 0.2-0.4%, Zr 0.03-0.06%, Ti 0.05-0.1%, Cr 0.3-0.5%, B 0.001-0.003%, and the balance being Cu and other unavoidable impurities.

2. The process for the prevention of electrochemical corrosion of corrosion resistant copper track according to claim 1, wherein, The rare earth elements are Ce, Nd and Pr mixed in a mass ratio of 2:(1-2):(0.8-1.2).

3. The process for the prevention of electrochemical corrosion of corrosion resistant copper track according to claim 1, wherein, The thickness of the nanocrystalline transition layer is 5-8 μm; and the thickness of the surface protective layer is 10-15 μm.

4. The process for electrochemical corrosion prevention of corrosion resistant copper track of claim 1, wherein, The stage cleaning specifically comprises: first ultrasonic cleaning with acetone for 10-15 min, then rinsing with deionized water, then acid pickling for 3-5 min, and finally rinsing with deionized water and drying; the acid pickling uses a 1-3% sulfuric acid solution, and the acid pickling temperature is 35-40 ℃.

5. The process for electrochemical corrosion prevention of corrosion resistant copper slot wire according to claim 1, wherein The pulse plating has the following pulse parameters: forward current density 11-13 A / dm², reverse current density 2-4 A / dm², pulse frequency 1000 Hz, duty cycle 60%, temperature 53-57 ℃, and deposition time 28-32 min.

6. The process for electrochemical corrosion prevention of corrosion resistant copper slot wire according to claim 1, wherein The pulse plating plating solution comprises the following components at the following concentrations: nickel sulfate 20-30 g / L, sodium hypophosphite 15-20 g / L, sodium citrate 10-15 g / L, cerium nitrate 3-5 g / L, zwitterionic salt 0.1-0.3 g / L, adenosine 0.1-0.5 g / L, 2,2'-biquinoline-4,4'-dicarboxylic acid disodium 0.05-0.1 g / L, and sulfuric acid is used to adjust the pH to 4.8-5.5; the zwitterionic salt is 1-benzylpyridine-3-carboxylate.

7. The process for electrochemical corrosion prevention of corrosion resistant copper slot-drag wire according to claim 1, wherein In step S3, the mass ratio of graphene oxide, hydroxyapatite, nanometer titanium dioxide, epoxy resin and curing agent is (3-5):(1-3):(4-6):(85-90):(4-6).

8. The process for electrochemical corrosion prevention of corrosion resistant copper slot-drag wire of claim 1, wherein, The graphene oxide is single-layer graphene oxide, the flake diameter is 0.5-5 mu m, and the thickness is 0.8-1.2 nm; the average diameter of the hydroxyapatite is 20-30 mu m; and the average particle size of the nano-titanium dioxide is 10-80 nm.

9. The process for electrochemical corrosion prevention of corrosion resistant copper slot-drag wire according to claim 1, wherein The epoxy resin is E-51 epoxy resin; and the curing agent is 3,3'-diamino-4,4'-difluorodiphenyl sulfone.

10. A corrosion-resistant copper slot wire made by an electrochemical corrosion prevention process using the corrosion-resistant copper slot wire according to any one of claims 1-9.