A high-conductivity phosphor bronze alloy and its surface treatment process

Abstract

This invention discloses a high-conductivity phosphor bronze alloy and its surface treatment process, relating to the field of copper alloy surface treatment technology. The specific steps of the surface treatment process are as follows: after cleaning the phosphor bronze alloy, it is sandblasted, then coated with a composite coating, and pyrolytic annealed to obtain an intermediate layer; an epoxy composite coating is coated on the surface of the intermediate layer, and cured at 40-45℃ for 20-24 hours to form a surface layer; wherein the raw material components of the composite coating include, by mass, 5-8 parts of phosphor bronze doped with molybdenum disulfide, 1-3 parts of copper powder, 0.2-3 parts of metal salt, 20-30 parts of aniline trimer derivative and 60-80 parts of N,N-dimethylformamide; the raw material components of the epoxy composite coating include, by mass, 80-100 parts of epoxy resin, 1-3 parts of modified MXene, 1-3 parts of phosphor bronze doped with molybdenum disulfide and 60-75 parts of curing agent.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of phosphor copper alloy surface treatment, in particular to a high-conductivity phosphor copper alloy and a surface treatment process thereof. BACKGROUND

[0002] With the development of electrified trains towards high speed and heavy load, the operating conditions of traction motors as the core equipment of the power traction system are becoming more and more severe, and higher requirements are put forward for the material and performance of the equipment, which promotes the technological progress of high-end materials, especially high-performance copper alloy materials, and the breakthrough of key technologies is emerging continuously. Therefore, the prospect of industrialization of the high-conductivity and easy-to-weld phosphor copper alloy material series products for rail transit traction motors is very broad. The conductor bar and end ring processed by the high-phosphor copper alloy material solve the problem of conductivity of the rotor conductor bar, but in the humid and salty rail transit environment, the copper surface is easy to be corroded to form a loose oxide film, and the falling off of the oxide film will cause the interruption of the conductive path, and in severe cases, it will cause motor failure.

[0003] Therefore, the phosphor copper alloy still faces the key problems of insufficient surface performance such as easy wear and corrosion in the long-term service of the traction motor, and it is urgent to further strengthen through surface treatment technology. SUMMARY

[0004] The purpose of the present application is to provide a high-conductivity phosphor copper alloy and a surface treatment process thereof to solve the problems in the prior art.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0006] A surface treatment process of a high-conductivity phosphor copper alloy, comprising the following process steps: after cleaning the phosphor copper alloy, the surface is subjected to sand blasting treatment, then composite coating is coated, the intermediate layer is obtained by pyrolysis and annealing, then epoxy composite coating is coated on the surface of the intermediate layer, and the surface layer is formed by solidification.

[0007] Preferably, the preparation steps of the composite coating include:

[0008] S1: placing aniline and 4,4'-diamino diphenylamine sulfate in a hydrochloric acid solution, stirring and adding ammonium persulfate, stirring at 2-5 DEG C for 50-70 min, then filtering, washing and drying, adding p-xylylene glycol and anhydrous ethanol, passing nitrogen and reacting at 60-70 DEG C for 4-6 h, then filtering, washing and drying to obtain aniline trimer derivative, which is ready for use;

[0009] S2: mixing copper nitrate, sodium hydroxide, ethylenediamine, and hydrazine hydrate, heating to 55-60 DEG C for 4-5 h, centrifuging and drying to obtain copper powder; mixing thiourea, molybdate ammonium tetrahydrate in deionized water, stirring for 30-40 min, adding copper powder, hydrothermal reaction at 180-200 DEG C for 20-24 h, calcining with sodium hypophosphite at 500-550 DEG C for 2 h to obtain phosphorus copper doped molybdenum disulfide; mixing phosphorus copper doped molybdenum disulfide, copper powder, metal salt, and aniline trimer derivative in N,N-dimethylformamide, stirring and dispersing to obtain a composite coating.

[0010] Preferably, the raw material components of the composite coating include, by mass fraction: 5-8 parts of phosphorus copper doped molybdenum disulfide, 1-3 parts of copper powder, 0.2-3 parts of metal salt, 20-30 parts of aniline trimer derivative, and 60-80 parts of N,N-dimethylformamide;

[0011] Preferably, the raw material components of the aniline trimer derivative include, by mass fraction: 9-10 parts of aniline, 25-30 parts of 4,4'-diaminodiphenylamine sulfate, 10-20 parts of ammonium persulfate, and 5-10 parts of p-phenylenediformaldehyde;

[0012] Preferably, the raw material components of the phosphorus copper doped molybdenum disulfide include, by mass fraction: 8-10 parts of thiourea, 4-5 parts of molybdate ammonium tetrahydrate, 1-1.5 parts of copper powder, and 80-100 parts of sodium hypophosphite;

[0013] Preferably, the metal salt is one or a combination of nickel acetate, titanium acetate, chromium acetate, and lanthanum acetate;

[0014] Preferably, the preparation steps of the epoxy composite coating are as follows:

[0015] Step 1: mixing aniline and 4,4'-diaminodiphenylamine sulfate in a hydrochloric acid solution, stirring and dissolving, adding ammonium persulfate solution dropwise, stirring at 2-5 DEG C for 50-70 min, filtering and washing, drying, adding 5-fluorosalicylaldehyde and anhydrous ethanol, passing nitrogen gas, and reacting at 45-55 DEG C for 4-6 h, then filtering, washing, and drying to obtain a fluorine-containing aniline trimer derivative for standby;

[0016] Step 2: mixing carbon titaniumized aluminum, lithium fluoride, and hydrochloric acid, stirring for 24 h, washing to neutral, placing in a low-temperature alkali solution, ultrasonicating for 2-3 h, adding benzoic acid diazonium salt, stirring for 4-6 h, centrifuging, washing, and drying to obtain carboxylated MXene; placing the carboxylated MXene in N,N-dimethylformamide and methanol solvents, adding the fluorine-containing aniline trimer derivative, condensing agent, and catalyst, heating to 60 DEG C, stirring for 10-12 h, centrifuging, washing, and drying to obtain modified MXene;

[0017] Step 3: disperse the modified MXene and phosphorus copper doped molybdenum disulfide in the epoxy resin, add the curing agent, stir for 10 min, and then stand for defoaming.

[0018] Preferably, the raw material components of the fluorine-containing aniline trimer derivative include 9-10 parts of aniline, 25-30 parts of 4,4'-diamino diphenylamine sulfate, 10-20 parts of ammonium persulfate and 5-10 parts of 5-fluorosalicylaldehyde by mass fraction;

[0019] Preferably, the raw material components of the modified MXene include 8-10 parts of carboxylated MXene, 2-5 parts of fluorine-containing aniline trimer derivative, 0.1-0.2 parts of condensing agent and 0.1-0.2 parts of catalyst by mass fraction;

[0020] Preferably, the raw material components of the epoxy composite coating include 80-100 parts of epoxy resin, 1-3 parts of modified MXene, 1-3 parts of phosphorus copper doped molybdenum disulfide and 60-75 parts of curing agent by mass fraction;

[0021] Preferably, the pyrolysis process steps are: holding at 500-600 DEG C for 2h, then heating to 800-900 DEG C for 6-8h; the annealing process steps are: holding at 200-300 DEG C for 1-2h; the curing temperature is 40-45 DEG C, and the curing time is 20-24h;

[0022] Preferably, the thickness of the intermediate layer is 10-50 microns, and the thickness of the surface layer is 80-120 microns;

[0023] A high-conductivity phosphorus copper alloy is prepared by the above surface treatment process;

[0024] Compared with the prior art, the beneficial effects of the present application are:

[0025] 1. The application is aimed at the surface treatment of high-conductivity phosphor copper alloy substrates to prevent the decline in conductivity caused by surface oxidation of the phosphor copper alloy; after sandblasting the substrate surface, a composite coating is applied, which is composed of phosphor copper-doped molybdenum disulfide, copper powder, metal salt, and aniline trimer derivative. The doped phosphor copper in the molybdenum disulfide reduces the contact resistance between the coatings caused by element differences, preventing the hindering of the conductive transmission of the phosphor copper alloy substrate. On the other hand, the doped phosphor can form Cu3P dispersed in the molybdenum disulfide or directly doped into the molybdenum disulfide, improving the hardness of the overall doped phase. After applying the composite coating, pyrolysis is performed to carbonize the aniline trimer derivative in the coating, forming a micro-diffusion between the phosphor copper alloy substrate and the coating under high-temperature pyrolysis, improving the interlayer adhesion, and the nitrogen-doped carbon caused by carbonization fills the coating gaps, while the doped elements such as nickel, titanium, chromium, and lanthanum in the metal salt can refine the grains, enhancing the adhesion between the intermediate layer and the phosphor copper substrate, forming a dense coating with the doped molybdenum disulfide and copper powder, reducing the penetration of corrosive media; annealing after pyrolysis eliminates internal pores and stress in the coating;

[0026] 2. After forming an intermediate layer on the surface of the high-conductivity phosphor copper alloy substrate, an epoxy composite coating is applied to further protect the intermediate layer and improve long-term corrosion resistance. Specifically, the selection of each component in the epoxy composite coating: first, the phosphor copper-doped molybdenum disulfide in the intermediate layer cooperates with MXene to improve the conductivity, ensuring the conductivity continuity between the substrate-intermediate layer-surface layer; second, the fluorine-containing aniline trimer derivative is obtained by oxidizing coupling of aniline and 4,4'-diamino diphenylamine sulfate to obtain aniline trimer, and then performing aminoaldehyde condensation with 5-fluorosalicylaldehyde to obtain the fluorine-containing aniline trimer derivative, which is then grafted with carboxylated MXene to improve the dispersion uniformity of MXene and improve the compatibility with epoxy resin; by adding modified MXene and phosphor copper-doped molybdenum disulfide to the epoxy resin, the wear resistance and long-term corrosion resistance of the epoxy surface layer are further enhanced. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the application will be described below in a clear and complete manner. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the application.

[0028] In the experiment, the preparation steps of the carboxylated MXene are as follows: 5 g of carbon titanium aluminum is mixed with 6.25 g of lithium fluoride and 100 mL of 12 mol / L hydrochloric acid, stirred for 24 h, washed to neutral, placed in a 5 ℃ 1 mol / L sodium hydroxide solution, ultrasonic for 3 h, then 10 g of benzoic acid diazonium salt is added, stirred for 6 h, centrifuged, washed and dried to obtain the carboxylated MXene; wherein the carbon titanium aluminum is purchased from Xinyan Technology, and the item number is 1012;

[0029] The preparation steps of the benzoic acid diazonium salt are as follows: 20 mmol of sodium hydroxide and 20 mmol of p-aminobenzoic acid are mixed in 500 mL of deionized water, stirred under ice bath conditions, and 25 mmol of sodium nitrite salt is added, the pH is adjusted to be acidic, and the stirring is carried out for 1 h to obtain the benzoic acid diazonium salt;

[0030] The preparation steps of the copper powder are as follows: 50 mL of 0.1 mol / L copper nitrate solution is mixed with 750 mL of 20 mol / L sodium hydroxide, 5 mL of ethylenediamine and 0.8 mL of hydrazine hydrate are added, heated to 60 ℃ for reaction for 4 h, and then centrifuged and dried to obtain the copper powder;

[0031] The epoxy resin type is E51, and the curing agent type is D230, both of which are purchased from Jinan Qingtian Chemical Technology Co., Ltd.

[0032] The chemical composition of the phosphor copper alloy includes, by mass percentage: 0.0026% P, 0.0010% Zn, 99.97% Cu+Ag, and the rest of the inevitable impurity elements.

[0033] Embodiment 1: The embodiment provides a surface treatment process of a high-conductivity phosphor copper alloy, which comprises the following process steps:

[0034] Step 1: 4.66 g of aniline and 14.88 g of 4,4'-diamino diphenylamine sulfate are placed in 500 mL of 1 mol / L hydrochloric acid solution, and 100 mL of 10 g of ammonium persulfate in hydrochloric acid solution is added dropwise, stirred at 5 ℃ for 1 h, then filtered and washed, dried, mixed with 3 g of p-phenylenediamine and 100 mL of anhydrous ethanol, nitrogen is introduced, and the mixture is heated at 70 ℃ for 6 h, then filtered and washed, and dried to obtain aniline trimer derivative for standby; 3.82 g of thiourea, 1.88 g of molybdenum ammonium sulfate tetrahydrate are placed in deionized water, stirred for 30 min, then 0.40 g of copper powder is added, and the mixture is hydrothermally reacted at 200 ℃ for 20 h, then calcined with 40 g of sodium hypophosphite at 500 ℃ for 2 h to obtain phosphor copper doped molybdenum disulfide; the phosphor copper doped molybdenum disulfide, copper powder, chromium acetate and aniline trimer derivative are placed in N,N-dimethylformamide, stirred and dispersed to obtain a composite coating;

[0035] Step 2: 4.67 g of aniline and 14.87 g of 4,4'-diamino diphenylamine sulfate were placed in a 500 mL hydrochloric acid solution, and a 100 mL hydrochloric acid solution containing 10 g of ammonium persulfate was added dropwise under stirring. After stirring at 5℃ for 1 h, the reaction mixture was filtered, washed, and dried. Then, 3 g of 5-fluorosalicylaldehyde was added to the mixture, and the mixture was placed in 100 mL of anhydrous ethanol. Nitrogen was introduced, and the mixture was heated at 50℃ for 6 h. After filtration, washing, and drying, a fluorine-containing aniline trimer derivative was obtained for later use. 5 g of carboxylated MXene was placed in 90 mL of N,N-dimethylformamide and 10 mL of methanol solvent. 1 g of the fluorine-containing aniline trimer derivative, 0.1 g of carbodiimide, and 0.1 g of 4-dimethylaminopyridine were added, and the mixture was heated to 60℃ and stirred for 10 h. After centrifugation, washing, and drying, a modified MXene was obtained. The modified MXene and phosphorus-copper-doped molybdenum disulfide were dispersed in an epoxy resin, and a curing agent was added and stirred for 10 min. After standing and degassing, an epoxy composite coating was obtained.

[0036] Step 3: The phosphorus-copper alloy was cleaned with anhydrous ethanol, sandblasted with brown corundum, coated with the composite coating, and then pyrolyzed at 500℃ for 2 h, followed by heating to 900℃ for 6 h. After annealing at 200℃ for 2 h, a 50 μm-thick intermediate layer was obtained. An epoxy composite coating was applied on the surface of the intermediate layer, and the coating was cured at 40℃ for 20 h to form a 100 μm-thick surface layer.

[0037] The composite coating includes 5 parts of phosphorus-copper-doped molybdenum disulfide, 2 parts of copper powder, 1 part of chromium acetate, 20 parts of aniline trimer derivative, and 80 parts of N,N-dimethylformamide.

[0038] The epoxy coating includes 100 parts of epoxy resin, 1 part of modified MXene, 1 part of phosphorus-copper-doped molybdenum disulfide, and 60 parts of curing agent.

[0039] Example 2: A surface treatment process for a high-conductivity phosphorus-copper alloy is provided, which includes the following process steps:

[0040] Step 1: 4.66 g of aniline and 14.87 g of 4,4'-diaminodiphenylamine sulfate were placed in 500 mL of hydrochloric acid solution and stirred to dissolve. 100 mL of hydrochloric acid solution containing 10 g of ammonium persulfate was added dropwise. The mixture was stirred at 5 °C for 1 h, then filtered, washed, and dried. The resulting product was mixed with 3 g of terephthalaldehyde and placed in 100 mL of anhydrous ethanol. Nitrogen gas was introduced, and the mixture was kept at 70 °C for 6 h. The solid was then extracted and dried to obtain the aniline trimer derivative for later use. 3.82g of thiourea and 1.87g of ammonium molybdate tetrahydrate were placed in deionized water and stirred for 30 min. Then, 0.50g of copper powder was added and the mixture was hydrothermally reacted at 200℃ for 20 h. After that, it was calcined with 40g of sodium hypophosphite at 500℃ for 2 h to obtain copper-doped molybdenum disulfide. Copper-doped molybdenum disulfide, copper powder, nickel acetate, chromium acetate, lanthanum acetate and aniline trimer derivative were placed in N,N-dimethylformamide and stirred to disperse to obtain a composite coating.

[0041] Step 2: 4.66 g of aniline and 14.85 g of 4,4'-diaminodiphenylamine sulfate were placed in 500 mL of hydrochloric acid solution, stirred and dissolved, and 100 mL of hydrochloric acid solution containing 10 g of ammonium persulfate was added dropwise. The mixture was stirred at 5 °C for 1 h, filtered, washed, dried, and then mixed with 3 g of 5-fluorosalicylaldehyde in 100 mL of anhydrous ethanol. Nitrogen gas was introduced and the mixture was kept at 50 °C for 6 h. The solid was extracted and dried to obtain the fluoroaniline trimer derivative for later use; 5 g of carboxyl group MXene was placed in 90 mL of N,N-dimethylformamide and 10 mL of methanol solvent, and 1.5 g of fluoroaniline trimer derivative, 0.1 g of carbodiimide and 0.1 g of 4-dimethylaminopyridine were added. The mixture was heated to 60 °C and stirred for 10 h. After centrifugation, washing and drying, modified MXene was obtained. Modified MXene and copper phosphate doped molybdenum disulfide were dispersed in epoxy resin, and a curing agent was added and stirred for 10 min. After standing to degas, an epoxy composite coating was obtained.

[0042] Step 3: After cleaning the phosphor bronze alloy with anhydrous ethanol, it is sandblasted with brown corundum, then coated with a composite coating. After holding at 550℃ for 2 hours, the temperature is raised to 900℃ and held for 6 hours for pyrolysis, and then annealed at 300℃ for 2 hours to obtain an intermediate layer with a thickness of 50μm. An epoxy composite coating is then coated on the surface of the intermediate layer and cured at 40℃ for 20 hours to form a surface layer with a thickness of 100μm.

[0043] The composite coating, by weight, comprises: 6 parts of copper-doped molybdenum disulfide, 1 part of copper powder, 1 part of nickel acetate, 1 part of chromium acetate, 1 part of lanthanum acetate, 20 parts of aniline trimer derivative and 80 parts of N,N-dimethylformamide.

[0044] The epoxy coating comprises: 100 parts epoxy resin, 2 parts modified MXene, 2 parts phosphorus copper doped molybdenum disulfide and 60 parts curing agent.

[0045] Embodiment 3: The present embodiment provides a surface treatment process of high-conductivity phosphor copper alloy, comprising the following process steps:

[0046] Step 1: 4.66 g of aniline and 14.88 g of 4,4'-diamino diphenylamine sulfate are placed in a 500 mL hydrochloric acid solution, and a 100 mL hydrochloric acid solution containing 10 g of ammonium persulfate is added dropwise. After stirring and dissolving at 5°C for 1 h, the mixture is filtered, washed and dried. Then, 3 g of p-phenylenediamine is mixed with 100 mL of anhydrous ethanol, and nitrogen is introduced. After reacting at 70°C for 6 h, the solid is extracted, dried, and mixed with 3 g of p-phenylenediamine to obtain aniline trimer derivative; 3.82 g of thiourea, 1.87 g of ammonium molybdate tetrahydrate are placed in deionized water, stirred for 30 min, and then 0.60 g of copper powder is added. After hydrothermal reaction at 200°C for 20 h, the mixture is calcined with 40 g of sodium hypophosphite at 550°C for 2 h to obtain phosphor copper doped molybdenum disulfide; the phosphor copper doped molybdenum disulfide, copper powder, nickel acetate, chromium acetate, lanthanum acetate, and aniline trimer derivative are placed in N,N-dimethylformamide, and stirred and dispersed to obtain a composite coating;

[0047] Step 2: 4.65 g of aniline and 14.88 g of 4,4'-diamino diphenylamine sulfate are placed in a 500 mL hydrochloric acid solution, and a 100 mL hydrochloric acid solution containing 10 g of ammonium persulfate is added dropwise. After stirring and dissolving at 5°C for 1 h, the mixture is filtered, washed and dried. Then, 3 g of 5-fluorosalicylaldehyde is mixed with 100 mL of anhydrous ethanol, and nitrogen is introduced. After reacting at 50°C for 6 h, the solid is extracted, dried, and mixed with 3 g of p-phenylenediamine to obtain aniline trimer derivative; 5 g of carboxylated MXene is placed in 90 mL of N,N-dimethylformamide and 10 mL of methanol solvent, and 2 g of fluorine-containing aniline trimer derivative, 0.1 g of carbodiimide, and 0.1 g of 4-dimethylaminopyridine are added. After stirring and reacting at 60°C for 10 h, the mixture is centrifuged, washed and dried to obtain modified MXene; the modified MXene and phosphor copper doped molybdenum disulfide are dispersed in epoxy resin, and a curing agent is added and stirred for 10 min. After standing and degassing, an epoxy composite coating is obtained;

[0048] Step 3: The phosphor copper alloy is cleaned with anhydrous ethanol, and then sandblasted with brown corundum. Then, the composite coating is applied, and pyrolysis is performed at 600°C for 2 h, then heated to 900°C for 8 h, and then annealed at 300°C for 2 h to obtain an intermediate layer with a thickness of 50 μm; an epoxy composite coating is applied on the surface of the intermediate layer, and cured at 40°C for 20 h to form a surface layer with a thickness of 100 μm;

[0049] In the composite coating, 8 parts of phosphor copper doped molybdenum disulfide, 2 parts of copper powder, 1 part of nickel acetate, 1 part of chromium acetate, 1 part of lanthanum acetate, 20 parts of aniline trimer derivative, and 80 parts of N,N-dimethylformamide are included;

[0050] The epoxy coating comprises: 100 parts of epoxy resin, 3 parts of modified MXene, 2 parts of phosphorus copper doped molybdenum disulfide, and 60 parts of curing agent.

[0051] Comparative Example 1: As a control experiment of Example 3, the difference is that no metal salt is added in the composite coating; the specific steps are as follows:

[0052] Step 1: 4.66 g of aniline and 14.88 g of 4,4'-diamino diphenylamine sulfate are placed in 500 mL of hydrochloric acid solution, stirred and dissolved, 100 mL of hydrochloric acid solution containing 10 g of ammonium persulfate is added dropwise, stirred at 5°C for 1 h, then filtered and washed, dried, mixed with 3 g of p-phenylenediamine, and placed in 100 mL of anhydrous ethanol, nitrogen is introduced and reacted at 70°C for 6 h, then the solid is extracted and dried to obtain aniline trimer derivative for use; 3.82 g of thiourea, 1.87 g of ammonium molybdate tetrahydrate are placed in deionized water, stirred for 30 min, then 0.60 g of copper powder is added, hydrothermal reaction is carried out at 200°C for 20 h, then 40 g of sodium hypophosphite is calcined at 550°C for 2 h to obtain phosphorus copper doped molybdenum disulfide; the phosphorus copper doped molybdenum disulfide, copper powder and aniline trimer derivative are placed in N,N-dimethylformamide, stirred and dispersed to obtain a composite coating;

[0053] Step 2: 4.65 g of aniline and 14.88 g of 4,4'-diamino diphenylamine sulfate are placed in 500 mL of hydrochloric acid solution, stirred and dissolved, 100 mL of hydrochloric acid solution containing 10 g of ammonium persulfate is added dropwise, stirred at 5°C for 1 h, then filtered and washed, dried, mixed with 3 g of 5-fluorosalicylaldehyde, and placed in 100 mL of anhydrous ethanol, nitrogen is introduced and reacted at 50°C for 6 h, then the solid is extracted and dried to obtain fluorine-containing aniline trimer derivative for use; 5 g of carboxylated MXene is placed in 90 mL of N,N-dimethylformamide and 10 mL of methanol solvent, 2 g of fluorine-containing aniline trimer derivative, 0.1 g of carbodiimide and 0.1 g of 4-dimethylaminopyridine are added, and the temperature is raised to 60°C for stirring reaction for 10 h, then centrifugal washing and drying are carried out to obtain modified MXene; the modified MXene and phosphorus copper doped molybdenum disulfide are dispersed in epoxy resin, a curing agent is added, stirred for 10 min, then static defoaming is carried out to obtain an epoxy composite coating;

[0054] Step 3: The phosphorus copper alloy is cleaned with anhydrous ethanol, then sandblasted with brown corundum, then coated with the composite coating, heated to 900°C for 8 h after being kept at 600°C for 2 h for pyrolysis, then heated to 300°C for 2 h for annealing to obtain an intermediate layer with a thickness of 50 μm; the epoxy composite coating is coated on the surface of the intermediate layer, and the surface layer with a thickness of 100 μm is formed after curing at 40°C for 20 h;

[0055] The composite coating includes, in terms of mass parts: 8 parts of phosphorus copper doped molybdenum disulfide, 2 parts of copper powder, 20 parts of aniline trimer derivative, and 80 parts of N,N-dimethylformamide;

[0056] The epoxy coating includes: 100 parts of epoxy resin, 3 parts of modified MXene, 2 parts of phosphorus copper doped molybdenum disulfide, and 60 parts of curing agent.

[0057] Comparative Example 2: As a control experiment of Example 3, the difference is that the phosphorus copper doped molybdenum disulfide in the composite coating and the epoxy composite coating is replaced by molybdenum disulfide, and the specific steps are as follows:

[0058] Step 1: 4.66g of aniline and 14.88g of 4,4'-diaminodiphenylamine sulfate are placed in 500mL of hydrochloric acid solution, and 100mL of hydrochloric acid solution containing 10g of ammonium persulfate is added dropwise. After stirring at 5℃ for 1h, filter and wash, dry, and then mix with 3g of p-phenylenediamine and place in 100mL of anhydrous ethanol. Nitrogen is introduced and the reaction is carried out at 70℃ for 6h. After extracting the solid, drying is carried out to obtain aniline trimer derivative for standby. 3.82g of thiourea and 1.87g of molybdenum ammonium molybdate tetrahydrate are placed in deionized water and stirred for 30min. After hydrothermal reaction at 200℃ for 20h, calcination is carried out at 550℃ for 2h to obtain molybdenum disulfide. The molybdenum disulfide, copper powder, nickel acetate, chromium acetate, lanthanum acetate, and aniline trimer derivative are placed in N,N-dimethylformamide, and stirring and dispersion are carried out to obtain a composite coating;

[0059] Step 2: 4.65g of aniline and 14.88g of 4,4'-diaminodiphenylamine sulfate are placed in 500mL of hydrochloric acid solution, and 100mL of hydrochloric acid solution containing 10g of ammonium persulfate is added dropwise. After stirring at 5℃ for 1h, filter and wash, dry, and then mix with 3g of 5-fluorosalicylaldehyde and place in 100mL of anhydrous ethanol. Nitrogen is introduced and the reaction is carried out at 50℃ for 6h. After extracting the solid, drying is carried out to obtain fluorine-containing aniline trimer derivative for standby. 5g of carboxylated MXene is placed in 90mL of N,N-dimethylformamide and 10mL of methanol solvent, and 2g of fluorine-containing aniline trimer derivative, 0.1g of carbodiimide, and 0.1g of 4-dimethylaminopyridine are added. After stirring at 60℃ for 10h, centrifugal washing and drying are carried out to obtain modified MXene. The modified MXene and molybdenum disulfide are dispersed in epoxy resin, and a curing agent is added and stirred for 10min. After standing and degassing, an epoxy composite coating is obtained;

[0060] Step 3: After the phosphor copper alloy is cleaned with anhydrous ethanol and then subjected to sand blasting treatment with brown corundum, a composite coating is coated, pyrolysis is performed at 600 ℃ for 2 h, then the temperature is raised to 900 ℃ for 8 h, and then annealing is performed at 300 ℃ for 2 h to obtain an intermediate layer with a thickness of 50 μm; an epoxy composite coating is coated on the surface of the intermediate layer, and curing is performed at 40 ℃ for 20 h to form a surface layer with a thickness of 100 μm;

[0061] In the composite coating, by mass fraction, 8 parts of molybdenum disulfide, 2 parts of copper powder, 1 part of nickel acetate, 1 part of chromium acetate, 1 part of lanthanum acetate, 20 parts of aniline trimer derivative, and 80 parts of N,N-dimethylformamide are included;

[0062] The epoxy coating includes 100 parts of epoxy resin, 3 parts of modified MXene, 2 parts of molybdenum disulfide, and 60 parts of a curing agent.

[0063] Comparative Example 3: As a control experiment of Example 3, the difference is that the modified MXene is replaced by MXene, and the specific steps are as follows:

[0064] Step 1: 4.66 g of aniline and 14.88 g of 4,4'-diamino diphenylamine sulfate are placed in a 500 mL hydrochloric acid solution, stirred and dissolved, 100 mL of a hydrochloric acid solution containing 10 g of ammonium persulfate is added dropwise, stirred at 5 ℃ for 1 h, then filtered and washed, dried, mixed with 3 g of p-phenylenediamine, placed in 100 mL of anhydrous ethanol, introduced with nitrogen, and reacted at 70 ℃ for 6 h, then the solid was extracted and dried to obtain an aniline trimer derivative for use; 3.82 g of thiourea, 1.87 g of molybdenum ammonium sulfate tetrahydrate are placed in deionized water, stirred for 30 min, 0.60 g of copper powder is added, hydrothermal reaction is performed at 200 ℃ for 20 h, then 40 g of sodium hypophosphite is calcined at 550 ℃ for 2 h to obtain phosphor copper doped molybdenum disulfide; the phosphor copper doped molybdenum disulfide, copper powder, nickel acetate, chromium acetate, lanthanum acetate, and aniline trimer derivative are placed in N,N-dimethylformamide, stirred and dispersed to obtain a composite coating;

[0065] Step 2: MXene and phosphor copper doped molybdenum disulfide are dispersed in epoxy resin, a curing agent is added, stirred for 10 min, and then left to stand to remove bubbles to obtain an epoxy composite coating;

[0066] Step 3: After the phosphor copper alloy is cleaned with anhydrous ethanol and then subjected to sand blasting treatment with brown corundum, a composite coating is coated, pyrolysis is performed at 600 ℃ for 2 h, then the temperature is raised to 900 ℃ for 8 h, and then annealing is performed at 300 ℃ for 2 h to obtain an intermediate layer with a thickness of 50 μm; an epoxy composite coating is coated on the surface of the intermediate layer, and curing is performed at 40 ℃ for 20 h to form a surface layer with a thickness of 100 μm;

[0067] The composite coating comprises, in terms of mass parts, 8 parts of phosphorus copper doped molybdenum disulfide, 2 parts of copper powder, 1 part of nickel acetate, 1 part of chromium acetate, 1 part of lanthanum acetate, 20 parts of aniline trimer derivative and 80 parts of N,N-dimethylformamide.

[0068] The epoxy coating comprises 100 parts of epoxy resin, 3 parts of MXene, 2 parts of phosphorus copper doped molybdenum disulfide and 60 parts of curing agent.

[0069] Detection test:

[0070] Adhesion test: The adhesion test was carried out according to GB / T9286-2021 "Paint and varnish: Cross-cut test", the temperature was 25 DEG C, the relative humidity was 50%, the cutting interval was 3mm, the cutting edge was completely smooth, and the falling off was 0 level standard, the falling off at the cutting edge was 1 level standard, the falling off at the cutting edge was 2 level standard, and the affected cross-cut area was not more than 5%.

[0071] Friction and wear performance test: The surface treated phosphorus copper alloy prepared in examples 1-3 and comparative examples 1-3 was taken, a multifunctional surface tester was used, a 6mm GCr bearing steel ball was used as the grinding material, a load of 20N was applied, the reciprocating speed was 100mm / min, the test was carried out for 30min, and the volume wear rate data was recorded in table 1.

[0072] Long-term corrosion resistance test: The test was carried out according to GB / T 10125-2021 neutral salt spray test, 3% sodium chloride neutral solution was used, the temperature was 35 DEG C, the test was carried out for 1600h, the surface of the sample was observed, the surface was intact without damage, and the sample was qualified, the rest was unqualified, and the record was recorded in table 1.

[0073] Table 1

[0074]

[0075] Conclusion: From the above data, it can be seen that the surface treatment process of example 3 is better than that of examples 1 and 2, and the interlayer adhesion, wear resistance and long-term corrosion resistance are excellent; the test performance is slightly affected by not adding metal salt in the composite coating of comparative example 1; the test performance is greatly affected by replacing the phosphorus copper doped molybdenum disulfide in the composite coating with molybdenum disulfide in comparative example 2; the compatibility between the filler and the resin is reduced and the fluorine-containing Schiff base grafting is lacking in comparative example 3, and the wear resistance and corrosion resistance are obviously reduced.

[0076] It will be apparent to those skilled in the art that the application is not limited to the details of the above-exemplified embodiments and that the present application can be implemented in other particular forms without departing from the spirit or essential characteristics of the present application. The embodiments should therefore be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the above description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims

1. A surface treatment process for high-conductivity phosphor copper alloys, characterized in that, The process comprises the following steps: sand blasting the surface of the phosphor copper alloy after cleaning, then coating the composite coating, pyrolyzing and annealing to obtain an intermediate layer, then coating an epoxy composite coating on the surface of the intermediate layer, and solidifying to form a surface layer. The preparation steps of the composite coating comprise: S1: aniline and 4,4'-diamino diphenylamine sulfate are placed in a hydrochloric acid solution, stirred, and ammonium persulfate is added, stirred at 2-5 DEG C for 50-70 min, then filtered, washed and dried, then para-xylene glycol is added and anhydrous ethanol is added, nitrogen is introduced and reacted at 60-70 DEG C for 4-6 h, then filtered, washed and dried to obtain aniline trimer derivative, which is used as needed; S2: copper nitrate, sodium hydroxide, ethylenediamine and hydrazine hydrate are mixed and heated to 55-60 DEG C for 4-5 h, then centrifuged and dried to obtain copper powder; thiourea, ammonium molybdate tetrahydrate are placed in deionized water, stirred for 30-40 min, then copper powder is added, and hydrothermal reaction is carried out at 180-200 DEG C for 20-24 h, then calcined with sodium hypophosphite at 500-550 DEG C for 2 h to obtain phosphor copper doped molybdenum disulfide; the phosphor copper doped molybdenum disulfide, copper powder, metal salt and aniline trimer derivative are placed in N,N-dimethylformamide, stirred and dispersed to obtain a composite coating; The raw material components of the composite coating include 5-8 parts of phosphor copper doped molybdenum disulfide, 1-3 parts of copper powder, 0.2-3 parts of metal salt, 20-30 parts of aniline trimer derivative and 60-80 parts of N,N-dimethylformamide; the raw material components of the aniline trimer derivative include 9-10 parts of aniline, 25-30 parts of 4,4'-diamino diphenylamine sulfate, 10-20 parts of ammonium persulfate and 5-10 parts of p-xylene glycol.

2. The process for surface treatment of high conductive phosphorous copper alloy as claimed in claim 1 wherein, The raw material components of the phosphor copper doped molybdenum disulfide include 8-10 parts of thiourea, 4-5 parts of ammonium molybdate tetrahydrate, 1-1.5 parts of copper powder and 80-100 parts of sodium hypophosphite; the metal salt is one or more combinations of nickel acetate, titanium acetate, chromium acetate and lanthanum acetate.

3. The process for surface treatment of high conductive phosphorous copper alloy as claimed in claim 1 wherein, The preparation steps of the epoxy composite coating are: Step 1: aniline and 4,4'-diamino diphenylamine sulfate are placed in a hydrochloric acid solution, stirred, and ammonium persulfate solution is added, stirred at 2-5 DEG C for 50-70 min, then filtered, washed and dried, then 5-fluorosalicylaldehyde and anhydrous ethanol are added, nitrogen is introduced and reacted at 45-55 DEG C for 4-6 h, then filtered, washed and dried to obtain fluorine-containing aniline trimer derivative, which is used as needed; Step 2: carbon titanium aluminum, lithium fluoride and hydrochloric acid are mixed and stirred for 24 h, then washed to neutral, placed in a low-temperature alkali solution and ultrasonicated for 2-3 h, then benzoic acid diazonium salt is added, stirred for 4-6 h, then centrifuged, washed and dried to obtain carboxylated MXene; the carboxylated MXene is placed in N,N-dimethylformamide and methanol solvents, fluorine-containing aniline trimer derivative, condensing agent and catalyst are added, and the temperature is raised to 60 DEG C for stirring for 10-12 h, then centrifuged, washed and dried to obtain modified MXene; Step 3: the modified MXene and the phosphor copper doped molybdenum disulfide are dispersed in epoxy resin, a curing agent is added and stirred for 10 min, then placed and degassed for standby.

4. The process for surface treatment of high conductive phosphorous copper alloy as claimed in claim 3 wherein, The raw material components of the fluorine-containing aniline trimer derivative include 9-10 parts of aniline, 25-30 parts of 4,4'-diamino diphenylamine sulfate, 10-20 parts of ammonium persulfate and 5-10 parts of 5-fluorosalicylaldehyde; the raw material components of the modified MXene include 8-10 parts of carboxylated MXene, 2-5 parts of the fluorine-containing aniline trimer derivative, 0.1-0.2 parts of a condensation agent and 0.1-0.2 parts of a catalyst.

5. The process for surface treatment of high conductive phosphorous copper alloy as claimed in claim 3 wherein, The raw material components of the epoxy composite coating include 80-100 parts of an epoxy resin, 1-3 parts of the modified MXene, 1-3 parts of phosphorus copper doped molybdenum disulfide and 60-75 parts of a curing agent.

6. The process for surface treatment of high conductive phosphorous copper alloy as claimed in claim 1 wherein, The process steps of the pyrolysis are: holding at 500-600 DEG C for 2 hours, then heating to 800-900 DEG C and holding for 6-8 hours; the process steps of the annealing are: holding at 200-300 DEG C for 1-2 hours; the curing temperature is 40-45 DEG C, and the curing time is 20-24 hours.

7. The process for surface treatment of high conductive phosphorous copper alloy as claimed in claim 1 wherein, The thickness of the intermediate layer is 10-50 microns; the thickness of the surface layer is 80-120 microns.

8. A high-conductivity phosphorous copper alloy characterized by, Prepared by the surface treatment process of any one of claims 1-7. Prepared by the surface treatment process of any one of claims 1-7.

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