A method of electroplating a molybdenum copper material

Abstract

The application relates to the technical field of metal electroplating, and particularly discloses an electroplating method of molybdenum copper material. The electroplating method of molybdenum copper material comprises the following steps: S1, molybdenum copper material is sequentially subjected to oil removal, water washing, oxidation, water washing, pickling, water washing, activation and water washing treatment to obtain pretreated molybdenum copper material; S2, the pretreated molybdenum copper material is first immersed in a nickel plating solution to perform bottom nickel plating, then immersed in a flash nickel plating solution to perform flash nickel plating, finally immersed in a nickel plating solution to perform nickel plating, and then subjected to water washing to obtain a nickel-plated molybdenum copper material; S3, the nickel-plated molybdenum copper material is immersed in a gold plating solution to perform gold plating, and then subjected to water washing to obtain a gold-plated nickel-plated molybdenum copper material; the nickel plating solution comprises a nickel salt, boric acid, a eutectic solvent, a chitosan-based ionic liquid, a brightener and a dispersant; the electroplating method has the advantages of simple steps, low cost, strong bonding force of the obtained nickel plating layer, smooth and flat surface and wide market prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metal electroplating, and more particularly to an electroplating method of molybdenum-copper material. BACKGROUND

[0002] Copper-molybdenum material, as a kind of high-performance alloy, has been widely used in many fields such as aerospace, electronics and electrical appliances, and mechanical manufacturing due to its excellent electrical conductivity, thermal conductivity, and high strength and hardness. In the electroplating process, the bonding force between the plating layer and the substrate material is a key factor to ensure the quality and performance of the plating layer. However, the surface hardness of copper-molybdenum material is high, and its chemical properties are stable, which makes it difficult to react with metal ions in the electroplating solution, resulting in that it is difficult for the plating layer to form a firm bond on the material surface. In addition, the thermal expansion coefficient of copper-molybdenum material is significantly different from that of commonly used electroplated metals, which also increases the risk of stress and blistering of the plating layer during heat treatment or use.

[0003] At present, CN118773690A discloses a method for plating nickel on a copper-molybdenum-copper layered composite material, which includes the following steps: 1) pretreatment: the copper-molybdenum-copper composite material parts are pretreated in a chain furnace under a hydrogen atmosphere to reduce the interface stress of the parts and remove organic impurities; 2) oil removal: the copper-molybdenum-copper composite material parts are soaked in an oil removal solution to remove oil stains and fingerprints on the surface of the parts; 3) immersion etching: the copper-molybdenum-copper composite material parts are soaked in an immersion etching solution and shaken quickly to remove the surface oxide scale and undesirable surface structure of the parts; 4) activation: the copper-molybdenum-copper composite material parts are soaked in an activation solution to further remove the residual oxide film on the surface of the parts and expose the base metal; 5) pre-plating nickel: high-current impact nickel plating is performed to improve the bonding force between the nickel layer and the base material; and 6) electroplating nickel: pulse electroplating nickel is performed using a nickel sulfate system. However, the problems of poor bonding force and blistering of the plated nickel layer after electroplating have not been completely solved, which not only affects the appearance and corrosion resistance of the plating layer, but also reduces the service life and reliability of the product. SUMMARY

[0004] To solve the problem of poor bonding force and easy blistering of the plated nickel layer after electroplating of the existing molybdenum-copper material, the present application provides an electroplating method of molybdenum-copper material.

[0005] The present application provides an electroplating method of molybdenum-copper material, which adopts the following technical scheme:

[0006] An electroplating method of molybdenum-copper material, including the following steps:

[0007] S1, the molybdenum-copper material is sequentially treated by oil removal, water washing, oxidation, water washing, pickling, water washing, activation, and water washing to obtain a pretreated molybdenum-copper material;

[0008] S2, the pretreated molybdenum copper material is first immersed in a nickel plating solution to plate a base nickel layer, then immersed in a flash nickel plating solution to plate a flash nickel layer, and finally immersed in a nickel plating solution to plate a nickel layer, and then washed with water to obtain a nickel-plated molybdenum copper material;

[0009] S3, the nickel-plated molybdenum copper material is immersed in a gold plating solution to plate a gold layer, and then washed with water to obtain a gold-plated nickel-molybdenum copper material;

[0010] The nickel plating solution comprises the following components in mass concentration: nickel salt 80-110 g / L, boric acid 40-50 g / L, eutectic solvent 50-150 mg / L, chitosan-based ionic liquid 30-60 mg / L, brightener 15-45 mg / L, dispersant 40-80 mg / L, defoaming agent 50-70 mg / L, buffer 10-50 mg / L, and the balance is deionized water.

[0011] Preferably, the nickel salt is at least one of nickel chloride, nickel sulfamate, nickel sulfate, nickel carbonate, nickel acetate, nickel formate, and nickel borofluoride.

[0012] Preferably, the eutectic solvent is obtained by mixing salicylic acid, N,N-dimethylurea and distilled water in a molar ratio of 1:1:2.

[0013] Preferably, the chitosan-based ionic liquid is prepared by the following method:

[0014] Step A, 1.32 g of N-methylbenzimidazole and 2-2.5 g of dibromopropane are added to 50 mL of acetone, and the mixture is reacted at 45-55°C for 12-24 h. After the reaction, the solvent is removed by rotary evaporation to obtain an intermediate;

[0015] Step B, 1.5 g of the intermediate and 0.01-0.05 g of potassium carbonate are added to 50 mL of distilled water, and the mixture is stirred until uniform. Then, 1.0-1.8 g of chitosan is added and stirred until uniform. The mixture is refluxed at 110-120°C for 18-24 h. After the reaction, the mixture is cooled, filtered, washed with ethanol, and dried to obtain the chitosan-based ionic liquid.

[0016] Preferably, the brightener is obtained by mixing L-alanine benzyl ester p-toluenesulfonate and N-arylpyridine in a mass ratio of 3-7:10.

[0017] Preferably, the dispersant is at least one of polyethylene glycol, Tween, Span, lecithin, and rhamnolipid; and the defoaming agent is an organic silicon defoaming agent.

[0018] Preferably, the buffer is a mixture of dipotassium hydrogen phosphate, malic acid and sodium gluconate in a mass ratio of 6:3:1.

[0019] Preferably, the flash nickel liquid comprises the following mass concentration components: nickel sulfate 100 g / L, potassium carbonate 30 g / L, sodium alginate 40 mg / L, ethylene-acrylic acid copolymer 20 mg / L, carbazole 10 mg / L, and the balance is deionized water.

[0020] Preferably, the gold plating liquid comprises the following mass concentration components: sodium sulfite 10-20 g / L, malic acid 15-30 g / L, phytic acid 10-20 g / L, polydithiodipropyl sulfonic acid sodium 10-40 mg / L, sorbitol 10-30 mg / L, diethyl dithiophosphoric acid ammonium salt 20-80 mg / L, and the balance is deionized water.

[0021] Preferably, the parameters of the step S2 of plating base nickel are: an external magnetic field of 0.3-0.4 T, a temperature of 30-40℃, a current density of 4-8 A / dm 2 , a pulse frequency of 10 Hz, a duty cycle of 20%, and electroplating for 120-150 s; and the parameters of the plating nickel are: an external magnetic field of 0.6-0.8 T, a temperature of 40-60℃, a current density of 1-2 A / dm 2 , a pulse frequency of 10 Hz, a duty cycle of 30%, and electroplating for 300-360 s.

[0022] In summary, the present application has the following beneficial effects:

[0023] 1、In the electroplating process, the molybdenum copper material is first subjected to pretreatment operations of oil removal, oxidation, acid washing, activation and the like, so as to improve the activity and roughness of the surface of the molybdenum copper material, thereby enhancing the bonding force between the plating layer and the molybdenum copper material; then, during plating nickel, base nickel, flash nickel and nickel are plated, so as to form a thin and uniform nickel layer on the surface of the molybdenum copper material through three times of plating nickel, thereby well solving the problem of poor bonding force of the nickel plating layer after electroplating and easy blistering, improving the density and gloss of the plating layer; finally, gold plating is performed to form a gold layer on the nickel plating layer, thereby improving the conductivity, corrosion resistance and aesthetic degree of the molybdenum copper material; the electroplating method of the present application has simple steps, low cost and is suitable for industrialized production, and has very excellent market prospects.

[0024] 2、The nickel plating solution of the application comprises nickel salt, boric acid, eutectic solvent, chitosan-based ionic liquid, brightener, dispersant, defoaming agent, buffer, etc., the nickel salt is used as the main salt to provide divalent nickel ions for the plating solution, ensuring continuous nickel plating and being the main source of chemical composition of the nickel plating layer; the salicylic acid and N,N-dimethylurea are used as the eutectic solvent to improve the conductivity and electrochemical window of the nickel plating solution, which is helpful to obtain high-quality nickel plating layer and reduce the occurrence of side reactions, thereby improving the adhesion of the nickel plating layer; the N-methylbenzimidazole, dibromopropane and chitosan are used as raw materials to prepare the chitosan-based ionic liquid, which can form a complex with nickel ions to promote the deposition of metal nickel on the surface of copper-molybdenum material, accelerate the deposition speed, improve the electroplating efficiency and the quality of the nickel plating layer, and improve the compactness and uniformity of the nickel plating layer; the chitosan-based ionic liquid can also be used as a strengthening phase to enhance the hardness and corrosion resistance of the nickel plating layer, which is helpful to improve the wear resistance and corrosion resistance of the nickel plating layer; the mixture of L-alanine benzyl ester p-toluenesulfonate and N-arylpyridine is used as the brightener, and the two components have synergistic effect to significantly improve the brightness and adhesion of the nickel plating layer; the addition of the dispersant, defoaming agent and buffer can ensure the uniform distribution of nickel ions in the nickel plating solution and prevent the occurrence of agglomeration, thereby being helpful to form a uniform and compact nickel plating layer; the components in the nickel plating solution have synergistic effect and mutual assistance to improve the performance of the nickel plating solution and the quality of the nickel plating layer, and the formation of the nickel plating layer is also conducive to the subsequent gold plating process, effectively improving the comprehensive performance of the overall plating layer.

[0025] 3、The flash nickel plating solution of the application comprises nickel sulfate, potassium carbonate, sodium alginate, ethylene-acrylic acid copolymer and carbazole, the carbazole is used as the catalyst to promote the electroplating reaction, and the components interact with each other to rapidly form a thin and uniform nickel layer on the surface of the copper-molybdenum material, which can be used as the subsequent electroplated layer to significantly improve the adhesion between the nickel plating layer and the copper-molybdenum material. DETAILED DESCRIPTION

[0026] The application will be further described in detail below in combination with the preparation examples and the examples.

[0027] Preparation Example 1

[0028] The chitosan-based ionic liquid is prepared by the following method:

[0029] Step A, 1.32g of N-methylbenzimidazole and 2g of dibromopropane are added into 50mL of acetone, and the mixture is reacted at 45℃ for 24h, then the solvent is removed by rotary evaporation to obtain an intermediate;

[0030] Step B, 1.5g of the intermediate and 0.01g of potassium carbonate are added into 50mL of distilled water, and the mixture is stirred uniformly, then 1.0g of chitosan is added and stirred uniformly, and the mixture is refluxed at 110℃ for 24h, then the mixture is cooled, filtered, washed with ethanol and dried to obtain the chitosan-based ionic liquid.

[0031] Preparation Example 2

[0032] The chitosan-based ionic liquid was prepared by the following method:

[0033] Step A, 1.32g N-methyl benzimidazole, 2.2g dibromopropane were added into 50mL acetone, after reaction at 50℃ for 18h, the solvent was removed by rotary evaporation to obtain an intermediate;

[0034] Step B, 1.5g of the intermediate, 0.03g potassium carbonate were added into 50mL distilled water, after stirring uniformly, 1.4g chitosan was added and stirred uniformly, after reflux reaction at 115℃ for 20h, it was cooled, suction filtered, washed with ethanol and dried to obtain the chitosan-based ionic liquid.

[0035] Preparation Example 3

[0036] The chitosan-based ionic liquid was prepared by the following method:

[0037] Step A, 1.32g N-methyl benzimidazole, 2.5g dibromopropane were added into 50mL acetone, after reaction at 55℃ for 12h, the solvent was removed by rotary evaporation to obtain an intermediate;

[0038] Step B, 1.5g of the intermediate, 0.05g potassium carbonate were added into 50mL distilled water, after stirring uniformly, 1.8g chitosan was added and stirred uniformly, after reflux reaction at 120℃ for 18h, it was cooled, suction filtered, washed with ethanol and dried to obtain the chitosan-based ionic liquid.

[0039] Preparation Examples 4-6 and Comparative Preparation Examples 1-6 provide a nickel plating solution.

[0040] Preparation Example 4

[0041] The nickel plating solution comprises the following mass concentrations of components: nickel salt 80g / L, boric acid 40g / L, deep eutectic solvent 50mg / L, chitosan-based ionic liquid 30mg / L, brightener 15mg / L, dispersant 40mg / L, defoamer 50mg / L, buffer 10mg / L, and the balance is deionized water;

[0042] The nickel salt is nickel chloride; the deep eutectic solvent is obtained by mixing salicylic acid, N,N-dimethyl urea and distilled water in a molar ratio of 1:1:2; the chitosan-based ionic liquid is preparation example 1; the brightener is obtained by mixing L-alanine benzyl ester p-toluenesulfonate and N-aryl pyridine in a mass ratio of 3:10; the dispersant is polyethylene glycol; the defoamer is silicone defoamer BYK-037; the buffer is a mixture of dipotassium hydrogen phosphate, malic acid and sodium gluconate in a mass ratio of 6:3:1.

[0043] Preparation Example 5

[0044] The nickel plating solution comprises the following components with mass concentration: nickel salt 95 g / L, boric acid 45 g / L, eutectic solvent 100 mg / L, chitosan-based ionic liquid 45 mg / L, brightener 30 mg / L, dispersant 60 mg / L, defoamer 60 mg / L, buffer 30 mg / L, and the balance is deionized water;

[0045] The nickel salt is nickel sulfate; the eutectic solvent is obtained by mixing salicylic acid, N, N-dimethylurea and distilled water in a molar ratio of 1:1:2; the chitosan-based ionic liquid is prepared in Preparation Example 2; the brightener is obtained by mixing L-alanine benzyl ester p-toluenesulfonate and N-arylpyridine in a mass ratio of 1:2; the dispersant is Tween 80; the defoamer is silicone defoamer BYK-018; and the buffer is a mixture of dipotassium hydrogen phosphate, malic acid and sodium gluconate in a mass ratio of 6:3:1.

[0046] Preparation Example 6

[0047] The nickel plating solution comprises the following components with mass concentration: nickel salt 95 g / L, boric acid 45 g / L, eutectic solvent 100 mg / L, chitosan-based ionic liquid 45 mg / L, brightener 30 mg / L, dispersant 60 mg / L, defoamer 60 mg / L, buffer 30 mg / L, and the balance is deionized water;

[0048] The nickel salt is obtained by mixing nickel chloride and nickel acetate in a mass ratio of 1:1; the eutectic solvent is obtained by mixing salicylic acid, N, N-dimethylurea and distilled water in a molar ratio of 1:1:2; the chitosan-based ionic liquid is prepared in Preparation Example 3; the brightener is obtained by mixing L-alanine benzyl ester p-toluenesulfonate and N-arylpyridine in a mass ratio of 7:10; the dispersant is lecithin; the defoamer is silicone defoamer BYK-066N; and the buffer is a mixture of dipotassium hydrogen phosphate, malic acid and sodium gluconate in a mass ratio of 6:3:1.

[0049] Comparative Preparation Example 1

[0050] Comparative Preparation Example 1 is the same as Preparation Example 4 except that no chitosan-based ionic liquid is added, and the specific differences are as follows:

[0051] The nickel plating solution comprises the following components with mass concentration: nickel salt 95 g / L, boric acid 45 g / L, eutectic solvent 100 mg / L, chitosan-based ionic liquid 45 mg / L, brightener 30 mg / L, dispersant 60 mg / L, defoamer 60 mg / L, buffer 30 mg / L, and the balance is deionized water;

[0052] The nickel salt is nickel chloride; the eutectic solvent is obtained by mixing salicylic acid, N,N-dimethylurea and distilled water in a molar ratio of 1:1:2; the brightener is obtained by mixing L-alanine benzyl ester p-toluenesulfonate and N-arylpyridine in a mass ratio of 3:10; the dispersant is polyethylene glycol; the defoaming agent is silicone defoaming agent BYK-037; and the buffer is a mixture of dipotassium hydrogen phosphate, malic acid and sodium gluconate in a mass ratio of 6:3:1.

[0053] Comparative Preparation Example 2

[0054] Comparative Preparation Example 2 is the same as Preparation Example 4 except that 1-methylimidazole tetrafluoroborate is used to replace the chitosan-based ionic liquid in an equal mass, and the specific process is as follows:

[0055] The nickel plating solution comprises the following components in mass concentration: nickel salt 80 g / L, boric acid 40 g / L, eutectic solvent 50 mg / L, 1-methylimidazole tetrafluoroborate 30 mg / L, brightener 15 mg / L, dispersant 40 mg / L, defoaming agent 50 mg / L, buffer 10 mg / L, and the balance is deionized water.

[0056] The nickel salt is nickel chloride; the eutectic solvent is obtained by mixing salicylic acid, N,N-dimethylurea and distilled water in a molar ratio of 1:1:2; the brightener is obtained by mixing L-alanine benzyl ester p-toluenesulfonate and N-arylpyridine in a mass ratio of 3:10; the dispersant is polyethylene glycol; the defoaming agent is silicone defoaming agent BYK-037; and the buffer is a mixture of dipotassium hydrogen phosphate, malic acid and sodium gluconate in a mass ratio of 6:3:1.

[0057] Comparative Preparation Example 3

[0058] Comparative Preparation Example 3 is the same as Preparation Example 4 except that chitosan is used to replace the chitosan-based ionic liquid in an equal mass, and the specific process is as follows:

[0059] The nickel plating solution comprises the following components in mass concentration: nickel salt 80 g / L, boric acid 40 g / L, eutectic solvent 50 mg / L, chitosan 30 mg / L, brightener 15 mg / L, dispersant 40 mg / L, defoaming agent 50 mg / L, buffer 10 mg / L, and the balance is deionized water.

[0060] The nickel salt is nickel chloride; the eutectic solvent is obtained by mixing salicylic acid, N,N-dimethylurea and distilled water in a molar ratio of 1:1:2; the brightener is obtained by mixing L-alanine benzyl ester p-toluenesulfonate and N-arylpyridine in a mass ratio of 3:10; the dispersant is polyethylene glycol; the defoaming agent is silicone defoaming agent BYK-037; and the buffer is a mixture of dipotassium hydrogen phosphate, malic acid and sodium gluconate in a mass ratio of 6:3:1.

[0061] Comparative Preparation Example 4

[0062] Comparative Preparation Example 4 is the same as Preparation Example 4 except that no eutectic solvent is added, as follows:

[0063] The nickel plating solution comprises the following mass concentrations of components: nickel salt 80 g / L, boric acid 40 g / L, chitosan-based ionic liquid 30 mg / L, brightener 15 mg / L, dispersant 40 mg / L, defoamer 50 mg / L, buffer 10 mg / L, and the balance being deionized water;

[0064] The nickel salt is nickel chloride; the chitosan-based ionic liquid is that of Preparation Example 1; the brightener is a mixture of L-alanine benzyl ester p-toluenesulfonate and N-aryl pyridine in a mass ratio of 3:10; the dispersant is polyethylene glycol; the defoamer is silicone defoamer BYK-037; and the buffer is a mixture of dipotassium hydrogen phosphate, malic acid, and sodium gluconate in a mass ratio of 6:3:1.

[0065] Comparative Preparation Example 5

[0066] Comparative Preparation Example 5 is the same as Preparation Example 4 except that the brightener is only L-alanine benzyl ester p-toluenesulfonate, as follows:

[0067] The nickel plating solution comprises the following mass concentrations of components: nickel salt 80 g / L, boric acid 40 g / L, eutectic solvent 50 mg / L, chitosan-based ionic liquid 30 mg / L, brightener 15 mg / L, dispersant 40 mg / L, defoamer 50 mg / L, buffer 10 mg / L, and the balance being deionized water;

[0068] The nickel salt is nickel chloride; the eutectic solvent is a mixture of salicylic acid, N,N-dimethyl urea, and distilled water in a molar ratio of 1:1:2; the chitosan-based ionic liquid is that of Preparation Example 1; the brightener is L-alanine benzyl ester p-toluenesulfonate; the dispersant is polyethylene glycol; the defoamer is silicone defoamer BYK-037; and the buffer is a mixture of dipotassium hydrogen phosphate, malic acid, and sodium gluconate in a mass ratio of 6:3:1.

[0069] Comparative Preparation Example 6

[0070] Comparative Preparation Example 6 is the same as Preparation Example 4 except that the brightener is only N-aryl pyridine, as follows:

[0071] The nickel plating solution comprises the following mass concentrations of components: nickel salt 80 g / L, boric acid 40 g / L, eutectic solvent 50 mg / L, chitosan-based ionic liquid 30 mg / L, brightener 15 mg / L, dispersant 40 mg / L, defoamer 50 mg / L, buffer 10 mg / L, and the balance being deionized water;

[0072] The nickel salt is nickel chloride; the eutectic solvent is obtained by mixing salicylic acid, N,N-dimethylurea and distilled water in a molar ratio of 1:1:2; the chitosan-based ionic liquid is prepared in Preparation Example 1; the brightener is only N-arylpyridine; the dispersing agent is polyethylene glycol; the defoaming agent is silicone defoaming agent BYK-037; and the buffer is a mixture of dipotassium hydrogen phosphate, malic acid and sodium gluconate in a mass ratio of 6:3:1.

[0073] Preparation Example 7 provides a flash nickel liquid.

[0074] Preparation Example 7

[0075] The flash nickel liquid comprises the following mass concentration components: nickel sulfate 100 g / L, potassium carbonate 30 g / L, sodium alginate 40 mg / L, ethylene-acrylic acid copolymer 20 mg / L, carbazole 10 mg / L, and the balance is deionized water.

[0076] Preparation Examples 8-10 provide a gold plating liquid.

[0077] Preparation Example 8

[0078] The gold plating liquid comprises the following mass concentration components: sodium gold sulfite 10 g / L, malic acid 15 g / L, phytic acid 10 g / L, polydithiodipropyl sulfonic acid sodium 10 mg / L, sorbitol 10 mg / L, diethyl dithiophosphoric acid ammonium salt 20 mg / L, and the balance is deionized water.

[0079] Preparation Example 9

[0080] The gold plating liquid comprises the following mass concentration components: sodium gold sulfite 15 g / L, malic acid 25 g / L, phytic acid 15 g / L, polydithiodipropyl sulfonic acid sodium 30 mg / L, sorbitol 20 mg / L, diethyl dithiophosphoric acid ammonium salt 50 mg / L, and the balance is deionized water.

[0081] Preparation Example 10

[0082] The gold plating liquid comprises the following mass concentration components: sodium gold sulfite 20 g / L, malic acid 30 g / L, phytic acid 20 g / L, polydithiodipropyl sulfonic acid sodium 40 mg / L, sorbitol 30 mg / L, diethyl dithiophosphoric acid ammonium salt 80 mg / L, and the balance is deionized water.

[0083] Embodiments 1-3 provide a method for electroplating a molybdenum-copper material.

[0084] Embodiment 1

[0085] A method for electroplating a molybdenum-copper material, comprising the following steps:

[0086] S1, the molybdenum copper material is soaked in the oil removal powder, and the surface excess is removed by cleaning for 30 min; after the oil-removed molybdenum copper material is washed with water, it is immersed in a 40wt% dilute hydrochloric acid solution for 30 s for pickling to remove the surface oxides; after the acidification treatment of the molybdenum copper material, it is washed with water and immersed in a 20wt% dilute hydrochloric acid solution for 3 min for activation; after the activation treatment of the molybdenum copper material, it is washed with water to obtain a pretreated molybdenum copper material;

[0087] S2, the pretreated molybdenum copper material is first immersed in a nickel plating solution for base nickel plating, an external magnetic field is 0.3T, the temperature is 30 DEG C, the current density is 4A / dm 2 , the pulse frequency is 10Hz, the duty cycle is 20%, and the electroplating time is 120s; then it is immersed in a flash nickel plating solution for flash nickel plating, and finally it is immersed in a nickel plating solution for nickel plating, an external magnetic field is 0.6T, the temperature is 40 DEG C, the current density is 1A / dm 2 , the pulse frequency is 10Hz, the duty cycle is 30%, the electroplating time is 300s, and the material is washed with water to obtain a nickel-plated molybdenum copper material;

[0088] The nickel plating solution is prepared by the preparation example 4; the flash nickel plating solution is prepared by the preparation example 7;

[0089] S3, the nickel-plated molybdenum copper material is immersed in a gold plating solution for gold plating, an external magnetic field is 0.6T, the temperature is 50 DEG C, the pulse frequency is 10Hz, the duty cycle is 30%, the current density is 50A / dm 2 , the electroplating time is 10 min, and the material is washed with water to obtain a gold-plated nickel-plated molybdenum copper material;

[0090] The gold plating solution is prepared by the preparation example 8.

[0091] Example 2

[0092] A method for electroplating a molybdenum copper material, comprising the following steps:

[0093] S1, the molybdenum copper material is soaked in the oil removal powder, and the surface excess is removed by cleaning for 30 min; after the oil-removed molybdenum copper material is washed with water, it is immersed in a 40wt% dilute hydrochloric acid solution for 30 s for pickling to remove the surface oxides; after the acidification treatment of the molybdenum copper material, it is washed with water and immersed in a 20wt% dilute hydrochloric acid solution for 3 min for activation; after the activation treatment of the molybdenum copper material, it is washed with water to obtain a pretreated molybdenum copper material;

[0094] S2, the pretreated molybdenum copper material is first immersed in a nickel plating solution for base nickel plating, an external magnetic field is 0.35T, the temperature is 35 DEG C, the current density is 6A / dm 2 , the pulse frequency is 10Hz, the duty cycle is 20%, and the electroplating time is 135s; then it is immersed in a flash nickel plating solution for flash nickel plating, and finally it is immersed in a nickel plating solution for nickel plating, an external magnetic field is 0.7T, the temperature is 50 DEG C, the current density is 1.5A / dm2 , pulse frequency is 10Hz, duty cycle is 30%, plating time is 330s, water washing, to obtain the nickel-molybdenum-copper material plated with gold;

[0095] The nickel plating solution is prepared by the preparation example 5, and the flash nickel plating solution is prepared by the preparation example 7.

[0096] S3, the nickel-molybdenum-copper material is immersed in the gold plating solution to perform gold plating, the external magnetic field is 0.7T, the temperature is 50℃, the pulse frequency is 10Hz, the duty cycle is 30%, the current density is 50A / dm 2 , plating time is 10min, water washing, to obtain the nickel-molybdenum-copper material plated with gold;

[0097] The gold plating solution is prepared by the preparation example 9.

[0098] Example 3

[0099] A plating method of a molybdenum-copper material, comprising the following steps:

[0100] S1, the molybdenum-copper material is immersed in the oil removal powder, and cleaned for 30min to remove the surface excess; after the oil removal, the molybdenum-copper material is washed with water, immersed in a 40wt% dilute hydrochloric acid solution for 30s to perform acid washing, and remove the surface oxides; after the acid treatment, the molybdenum-copper material is washed with water, immersed in a 20wt% dilute hydrochloric acid solution for 3min to perform activation; after the activation treatment, the molybdenum-copper material is washed with water, to obtain the pretreated molybdenum-copper material;

[0101] S2, the pretreated molybdenum-copper material is first immersed in the nickel plating solution to perform nickel plating, the external magnetic field is 0.4T, the temperature is 40℃, the current density is 8A / dm 2 , pulse frequency is 10Hz, duty cycle is 20%, plating time is 150s; then immersed in the flash nickel plating solution to perform flash nickel plating, and finally immersed in the nickel plating solution to perform nickel plating, the external magnetic field is 0.8T, the temperature is 60℃, the current density is 2A / dm 2 , pulse frequency is 10Hz, duty cycle is 30%, plating time is 360s, water washing, to obtain the nickel-molybdenum-copper material plated with gold;

[0102] The nickel plating solution is prepared by the preparation example 6, and the flash nickel plating solution is prepared by the preparation example 7.

[0103] S3, the nickel-molybdenum-copper material is immersed in the gold plating solution to perform gold plating, the external magnetic field is 0.6-0.8T, the temperature is 50℃, the pulse frequency is 10Hz, the duty cycle is 30%, the current density is 50A / dm 2 , plating time is 10min, water washing, to obtain the nickel-molybdenum-copper material plated with gold;

[0104] The gold plating solution is prepared by the preparation example 10.

[0105] In order to verify the performance of the gold-plated nickel-molybdenum-copper material provided in the present application, the applicant sets up Comparative Examples 1-6, wherein:

[0106] Comparative Example 1

[0107] Comparative Example 1, which is different from Example 1 only in that the nickel plating solution is prepared according to Comparative Preparation Example 1.

[0108] Comparative Example 2

[0109] Comparative Example 2, which is different from Example 1 only in that the nickel plating solution is prepared according to Comparative Preparation Example 2.

[0110] Comparative Example 3

[0111] Comparative Example 3, which is different from Example 1 only in that the nickel plating solution is prepared according to Comparative Preparation Example 3.

[0112] Comparative Example 4

[0113] Comparative Example 4, which is different from Example 1 only in that the nickel plating solution is prepared according to Comparative Preparation Example 4.

[0114] Comparative Example 5

[0115] Comparative Example 5, which is different from Example 1 only in that the nickel plating solution is prepared according to Comparative Preparation Example 5.

[0116] Comparative Example 6

[0117] Comparative Example 6, which is different from Example 1 only in that the nickel plating solution is prepared according to Comparative Preparation Example 6.

[0118] The nickel plating layer adhesion, soldering verification and hardness of the nickel-molybdenum-copper material obtained in step S2 in Examples 1-3 and Comparative Examples 1-6 are detected respectively, and the following results are obtained, as shown in Table 1:

[0119] Nickel plating layer adhesion: the nickel-molybdenum-copper material is placed in a 250°C oven for 30 minutes, and immediately immersed in room temperature water after being taken out, and dried after being taken out; under an 8-fold magnification illumination observation system, it is checked whether the plating layer has blistering and separation phenomena;

[0120] Soldering verification: AgCu28 solder, 4J50 frame and the nickel-molybdenum-copper material are soldered at 890°C, and after soldering, the appearance of the experimental piece is inspected according to GJB923A-2004 "General Specification for Semiconductor Discrete Device Enclosure", and the nickel plating layer should not have problems such as blistering, copper corrosion, tearing, etc.

[0121] Hardness: the Vickers hardness value of the nickel plating layer of the nickel-molybdenum-copper material is measured by the micro Vickers hardness method using a HVS-1000 type micro Vickers hardness tester.

[0122] Table 1:

[0123]

[0124]

[0125] From the data shown in Table 1, it can be seen that the comprehensive performance of the gold-plated nickel-molybdenum-copper material obtained in the embodiments 1-3 is far superior to that of the gold-plated nickel-molybdenum-copper material obtained in the comparative examples 1-6, the hardness of the nickel-plated layer is larger, the surface bonding strength of the nickel-plated layer to the copper-molybdenum material is better, and the surface is smooth and bubble-free.

[0126] From the embodiments 1 and the comparative examples 1-3, it can be seen that the nickel-plating solution in the embodiment 1 is prepared by the preparation example 4, and the chitosan-based ionic liquid in the preparation example 4 is prepared by the preparation example 1. Compared with the comparative examples 1-3, the stability of the nickel-plating solution prepared by the preparation example 4 is better, the plating layer of the nickel-molybdenum-copper material obtained in the embodiment 1 is bubble-free, and the plating layer does not appear tearing phenomenon after brazing.

[0127] From the embodiments 1 and the comparative example 4, it can be seen that the nickel-plating solution in the embodiment 1 is prepared by the preparation example 4, and the eutectic solvent is added in the preparation example 4. Compared with the comparative example 4, the comprehensive performance of the nickel-molybdenum-copper material obtained in the embodiment 1 is greatly improved.

[0128] From the embodiments 1 and the comparative examples 5 and 6, it can be seen that the nickel-plating solution in the embodiment 1 is prepared by the preparation example 4, and the brightener in the preparation example 4 is obtained by mixing L-alanine benzyl ester p-toluenesulfonate and N-arylpyridine. Compared with the comparative examples 5 and 6, the stability of the nickel-plating solution prepared by the preparation example 4 is better, the brightness of the nickel-plated layer of the nickel-molybdenum-copper material obtained in the embodiment 1 is significantly improved, the bonding force of the nickel-plated layer is strong, and there is no bubble.

[0129] The specific embodiments are only an explanation of the present application, and are not a limitation of the present application. Those skilled in the art can make modifications to the embodiments without creative contribution after reading the present specification, and the modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A method for electroplating molybdenum-copper material, characterized in that: The following steps are involved: S1. The molybdenum-copper material is sequentially subjected to degreasing, water washing, oxidation, water washing, pickling, water washing, activation, and water washing to obtain a pretreated molybdenum-copper material; S2, pretreated molybdenum-copper material is first immersed in nickel plating solution to carry out bottom nickel plating, then immersed in nickel flash solution to carry out nickel flash, finally immersed in nickel plating solution nickel plating, washed, and obtained nickel-plated molybdenum-copper material; S3, immersing the nickel-molybdenum-copper material in a gold plating solution for gold plating, and washing with water to obtain a gold-plated nickel-molybdenum-copper material; the nickel plating solution comprises the following components in mass concentrations: nickel salt 80-110 g / L, boric acid 40-50 g / L, deep eutectic solvent 50-150 mg / L, chitosan-based ionic liquid 30-60 mg / L, brightener 15-45 mg / L, dispersant 40-80 mg / L, defoamer 50-70 mg / L, buffer 10-50 mg / L, and the balance is deionized water; The deep eutectic solvent is prepared by mixing salicylic acid, N,N-dimethylurea and distilled water in a molar ratio of 1:1:2; The chitosan-based ionic liquid is prepared by the following method: Step A: Add 1.32 g of N-methylbenzimidazole and 2-2.5 g of dibromopropane to 50 mL of acetone, react at 45-55° C. for 12-24 hours, and then remove the solvent by rotary evaporation to obtain an intermediate; Step B, adding 1.5 g of the intermediate and 0.01-0.05 g of potassium carbonate to 50 mL of distilled water, stirring evenly, adding 1.0-1.8 g of chitosan and stirring evenly, reacting at 110-120° C. for 18-24 hours, cooling, filtering, washing with ethanol, and drying to obtain a chitosan-based ionic liquid; The brightener is obtained by mixing L-alanine benzyl ester p-toluenesulfonate and N-aryl pyridine in a mass ratio of 3-7:10; The dispersant is at least one of polyethylene glycol, Tween, Span, and rhamnolipid; and the defoaming agent is an organosilicon defoaming agent.

2. The electroplating method of a molybdenum-copper material according to claim 1, characterized in that: The nickel salt is at least one of nickel chloride, nickel sulfamate, nickel sulfate, nickel carbonate, nickel acetate, nickel formate, and nickel borofluoride.

3. The electroplating method of a molybdenum-copper material according to claim 1, characterized in that: The buffer is a mixture of dipotassium hydrogen phosphate, malic acid and sodium gluconate in a mass ratio of 6:3:

1.

4. The electroplating method of a molybdenum-copper material according to claim 1, characterized in that: The nickel flash solution includes the following components by mass concentration: 100 g / L nickel sulfate, 30 g / L potassium carbonate, 40 mg / L sodium alginate, 20 mg / L ethylene-acrylic acid copolymer, 10 mg / L carbazole, and the balance is deionized water.

5. The electroplating method of a molybdenum-copper material according to claim 1, characterized in that: The gold plating solution comprises the following components in mass concentrations: 10-20 g / L of sodium gold sulfite, 15-30 g / L of malic acid, 10-20 g / L of phytic acid, 10-40 mg / L of sodium polydisulfide propane sulfonate, 10-30 mg / L of sorbitol, and 20-80 mg / L of diethyl dithiophosphate ammonium salt, with the balance being deionized water.

6. The electroplating method of a molybdenum-copper material according to claim 1, characterized in that: The parameters of the nickel plating in step S2 are: external magnetic field of 0.3-0.4T, temperature of 30-40°C, current density of 4-8A / dm 2 , pulse frequency is 10Hz, duty cycle is 20%, electroplating is 120-150s; the parameters of the nickel plating are: external magnetic field is 0.6-0.8T, temperature is 40-60℃, current density is 1-2A / dm 2 , the pulse frequency is 10Hz, the duty cycle is 30%, and the electroplating time is 300-360s.

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