阅读说明：本技术 铝合金表面一次施镀银的环保镀银工艺 (The environmentally friendly silver plating process of aluminum alloy surface plating silver ) 是由 陈云翔 蔡振才 林德源 洪毅成 蔡建宾 韩纪层 严康骅 夏晓健 邵艳群 于 2019-09-03 设计创作，主要内容包括：本发明属于铝合金电镀技术领域,具体涉及铝合金表面一次施镀银的环保镀银工艺。具体包括：表面打磨光滑、粗化处理、羟基化处理、KH580表面改性、环保镀银。本发明通过在Al及Al合金上一次直接施镀银层,银层致密,厚度薄且均匀,有效提高Ag与Al之间结合力,在不降低质量的情况下可大大降低成本。从环保角度和环境可持续发展方面因为不使用氰化水溶液解决了环境污染和毒害问题。(The invention belongs to plating on aluminium alloy technical fields, and in particular to the environmentally friendly silver plating process of aluminum alloy surface plating silver.Specifically include: surface polishes smooth, roughening treatment, hydroxylating processing, the surface KH580 is modified, environmental protection is silver-plated.The present invention is by directly plating silver layer primary on Al and Al alloy, and silver layer is fine and close, and thickness is thin and uniform, effectively improves binding force between Ag and Al, and cost can be substantially reduced in the case where not reducing quality.Because solving the problems, such as environmental pollution and murder by poisoning without using cyaniding aqueous solution in terms of environmental angle and environment sustainable development.)

1. a kind of environmentally friendly silver plating process of plating of aluminum alloy surface silver, it is characterised in that: specifically include: surface polishing light Cunning, roughening treatment, hydroxylating processing, the surface KH580 is modified, environmental protection is silver-plated.

2. a kind of environmentally friendly silver plating process of plating of aluminum alloy surface silver according to claim 1, it is characterised in that: will Aluminum alloy specimen surface polishes smooth, and then carries out the following processing technique:

Step S1 roughening treatment: the HCl solution of 2mL is added dropwise in 18mL deionized water, and adds 3.4g NH₄F, stirring and dissolving Obtain coarsening solution；Aluminum alloy specimen is immersed in coarsening solution, ultrasound 10 minutes, make roughing in surface under the conditions of low-frequency ultrasonic waves；

The processing of step S2 hydroxylating: step S1 treated sample is immersed NaOH by the NaOH solution that configuration quality score is 10% In solution, ultrasound 10 minutes under the conditions of low-frequency ultrasonic waves；

Step S3 KH580 surface modification treatment: KH580 is dissolved in ethyl acetate, modification liquid is obtained；After hydroxylating is handled Sample be put into modification liquid, under the conditions of low-frequency ultrasonic waves ultrasound 1 ~ 3 hour, make matrix surface obtain sulfydryl；

Step S4 environmental protection is silver-plated: by step S3, treated that sample is put into reducing solution, under condition of water bath heating, with every point Main salt solution is added dropwise into reducing solution in the speed that clock 20 ~ 50 drips；After 30 ~ 90 minutes, take out aluminum alloy specimen, using go from Sub- water cleans silver-plated layer surface plating solution.

3. a kind of environmentally friendly silver plating process of plating of aluminum alloy surface silver according to claim 2, it is characterised in that: step The volumetric concentration of KH580 is 0.5 ~ 3% in modification liquid described in rapid S3.

4. a kind of environmentally friendly silver plating process of plating of aluminum alloy surface silver according to claim 2, it is characterised in that: step Reducing solution concrete configuration method in rapid S4 are as follows: using glucose and tartaric acid mixing reduction, concentration of glucose is 15 ~ 40g/L, Tartaric acid concentration is 3 ~ 6g/L, after being completely dissolved, ethanol solution is added, 1-5g/L polyvinyl pyrrole is added after configuration is good Alkanone finally obtains reducing solution as additive.

5. a kind of environmentally friendly silver plating process of plating of aluminum alloy surface silver according to claim 4, it is characterised in that: Portugal Grape sugar and tartaric acid mixed liquor are mixed with dehydrated alcohol according to volume ratio 1:1.

6. a kind of environmentally friendly silver plating process of plating of aluminum alloy surface silver according to claim 2, it is characterised in that: step Water bath heating temperature described in rapid S4 is 50-90 DEG C.

7. a kind of environmentally friendly silver plating process of plating of aluminum alloy surface silver according to claim 2, it is characterised in that: step Main salt solution concrete configuration method in rapid S4 are as follows: use mass fraction for 1 ~ 3% silver nitrate solution, complexing agent is 1-3%'s 25% ammonium hydroxide after mixing, continues that 25% ammonium hydroxide is added dropwise in main salt solution, until precipitating fades away solution change clarification.

Technical field

The invention belongs to plating on aluminium alloy technical fields, and in particular to the silver-plated work of environmental protection of aluminum alloy surface plating silver Skill.

Background technique

Substation breakers, GIS external terminal board are mostly aluminum-alloy conductor material, and high temperature coastal industry corrosive environment is harsh, High Cl^-Aluminium conductor material corrosion is extremely serious under the complicated adverse circumstances of concentration.Aluminium and aluminum alloy surface silver plating process are complicated, and one As pass through electrochemical deoiling --- washing --- alkaline etching --- washing --- go out light --- washing --- once soak zinc and --- move back zinc --- washing --- --- --- --- --- silver-plated --- --- --- hot water wash --- drying --- is anti-for washing for recycling for washing for cyanide copper plating for washing for secondary soaking zinc Discoloration handles the processes such as --- drying --- inspection.Process is more, and quality is more uncontrollable.Outside breaker that substation uses, GIS The silver coating of terminal plate is all that aluminium copper facing is silver-plated again.In addition because more interface Al-Cu and Cu-Ag, increasing resistance leads to electricity The decline of gas performance.Find disposably on Al and its alloy directly it is silver-plated and improve silvering quality be contact material urgently It solves the problems, such as.

Silver-plated technology can totally be divided into metallurgy, chemistry, physics, machinery and synthesis.Although also proposed in above-mentioned technology Many non-cyaniding solution systems, but it is still that the important of electrosilvering industry is matched that cyanide, which is the solution system of main formula, at present Side.Replacement ag plating (also referred to as immersion silver) technique in chemical method is a kind of easy to operate, lower-cost silver-coating method.Displacement side Formula can only obtain silver in exposed surface, so to obtain very thin silvering or save silver-colored dosage, theoretically this is a kind of Very suitable reaction.The existing technology of replacement ag plating be still based on cyaniding water solution system and non-cyaniding water solution system, And the existing non-silver-plated technology of cyaniding water solution system is still inferior to cyanide as main water solution system.It explores and finds and is new The research of non-cyaniding aqueous solution be still current research emphasis.

The Chinese name of silane coupling agent KH580 is also known as three ethoxy of 3- mercaptopropyi gamma-mercaptopropyltriethoxysilane Base silane etc., it is not soluble in water, but it is dissolved in alcohol, it can slowly react with water.Ethyl is broken after hydrolysis, forms Si-OH structure, hydroxyl Base can carry out condensation reaction with hydroxyl.The present invention is by the way that when aluminum alloy surface hydroxylating pre-processes, elder generation is in NaOH solution Low frequency ultrasound 10 minutes, by the ethyl acetate solution of KH580, in hydroxylating, treated that matrix surface connects KH580.KH580 Hydroxyl and matrix surface hydroxy combining, sulfydryl is exposed outside.Sulfydryl can carry out complexation reaction with silver, by silver positioning absorption In matrix surface.The self-catalysis function of silver is recycled to carry out chemical silvering reaction in matrix surface.

Summary of the invention

The purpose of the present invention is to provide a kind of environmentally friendly silver plating process of plating of aluminum alloy surface silver.By being closed in Al Golden last directly plating silver layer, silver layer is fine and close, and thickness is thin and uniform, effectively improves binding force between Ag and Al, is not reducing Cost can be substantially reduced in the case where quality.Because not using cyaniding aqueous solution in terms of environmental angle and environment sustainable development Solve the problems, such as environmental pollution and murder by poisoning.

To achieve the above object, the present invention adopts the following technical scheme:

A kind of environmentally friendly silver plating process of plating of aluminum alloy surface silver specifically includes: chemical plating process: surface polishes smooth → Roughening treatment → hydroxylating processing → surface KH580 is modified → environmentally friendly silver-plated.

Specific embodiment is as follows:

Step S1 roughening treatment: the HCl solution of 2mL is added dropwise in 18mL deionized water, and adds 3.4g NH₄F is stirred molten Solution obtains coarsening solution；Aluminum alloy specimen is immersed in coarsening solution, ultrasound 10 minutes, keep surface thick under the conditions of low-frequency ultrasonic waves Change；

The processing of step S2 hydroxylating: step S1 treated sample is immersed NaOH by the NaOH solution that configuration quality score is 10% In solution, ultrasound 10 minutes under the conditions of low-frequency ultrasonic waves；

Step S3 KH580 surface modification treatment: KH580 is dissolved in ethyl acetate, and volumetric concentration is 0.5 ~ 3%, is modified Liquid；By hydroxylating, treated that sample is put into modification liquid, and ultrasound 1 ~ 3 hour, makes matrix surface under the conditions of low-frequency ultrasonic waves Obtain sulfydryl；

Step S4 environmental protection is silver-plated: by step S3, treated that sample is put into reducing solution, under 50-90 DEG C of heating condition of water-bath, Main salt solution is added dropwise into reducing solution with the speed of 20 ~ 50 drop per minute；After 30 ~ 90 minutes, aluminum alloy specimen is taken out, is made Silver-plated layer surface plating solution is cleaned with deionized water.

Further, the reducing solution concrete configuration method in step S4 are as follows: using glucose and tartaric acid mixing reduction, Portugal Grape sugar concentration is 15 ~ 40g/L, and tartaric acid concentration is 3 ~ 6g/L, and after being completely dissolved, ethanol solution is added by 1:1 by volume, Obtain reducing solution；1-5g/L polyvinylpyrrolidone is added after reducing solution configures as additive.

Further, the main salt solution concrete configuration method in step S4 are as follows: use mass fraction for 1 ~ 3% silver nitrate Solution, complexing agent is 25% ammonium hydroxide of 1-3%, after mixing, continues that 25% ammonium hydroxide is added dropwise in main salt solution, until precipitating gradually disappears Until losing solution change clarification.

Remarkable advantage of the invention is:

The present invention by the way that in the primary direct plating silver layer of aluminum alloy surface, silver layer is fine and close, and thickness is thin and uniform, effectively improve Ag with Binding force between Al can substantially reduce cost in the case where not reducing quality.Not only greatly reduce aluminium alloy cyaniding plant of silver The pollution of issuable heavy metal and cyanide to environment, and avoid that HCN etc. can be generated in existing removal process is toxic Gas secondary pollution problems.

Detailed description of the invention

Whether there is or not the comparisons of the XRD spectrum of silver coating for Fig. 1 aluminium alloy；

The microscopic appearance of silver coating after Fig. 2 different pretreatments；(a) only roughening treatment；(b) roughening+KH580 is handled;(c) thick Change processing+hydroxylating processing+KH580 modification；

By 90 minutes silver-plated sample patterns after Fig. 3 addition 4g/L polyvinylpyrrolidone；

Silver-plated layer surface power spectrum after additive is added in Fig. 4；

Influence of Fig. 5 different pretreatments to silvering sample contacts resistance；

Influence of Fig. 6 silver-plated time to sample resistance value.

Specific embodiment

Further to disclose rather than the present invention is limited, the present invention is described in further detail below in conjunction with example.