CN104294239A - Preparation method of activating solution for nickel plating pretreatment of aluminum alloy for electronic devices - Google Patents

Abstract

The invention discloses a preparation method of an activating solution for nickel plating pretreatment of an aluminum alloy for electronic devices. The activating solution comprises 52-56g/L of nickel sulfate, 18-22g/L of sodium phosphate, 22-26g/L of citric acid, 15-19g/L of ammonium sulfate, 12-16g/L of zinc dihydrogen phosphate, 6-8g/L of zinc oxide, 65-75g/L of sodium hydroxide, 6-10g/L of ferrous chloride, 10-14g/L of potassium sodium tartrate, and the balance of water. The preparation method comprises the following steps: 1, dissolving sodium hydroxide in water, adding zinc oxide while stirring, adding zinc dihydrogen phosphate after zinc oxide is completely dissolved, and stirring for 8-12min; 2, adding a proper amount of water into another container, sequentially adding nickel sulfate, sodium phosphate, citric acid, ammonium sulfate, ferrous chloride and potassium sodium tartrate, and stirring for 8-12min; and 3, adding the solution prepared in step 2 to the solution prepared in step 1, adding water to a constant volume, and filtering.

Description

A kind of aluminum alloy nickel plated pre-treatment activation solution compound method used for electronic device

Technical field

The present invention relates to technical field of surface, particularly relate to a kind of aluminum alloy nickel plated pre-treatment activation solution compound method used for electronic device.

Background technology

Because aluminium is a kind of active metal, Al and Alalloy surface is easy to react with the oxygen in air, steam the oxide film forming layer, and this layer of oxide film can cause metal plating and aluminum substrate sticking power not strong, does not reach processing requirement.So Al and Alalloy must carry out having good sticking power when eliminating the activation treatment of oxide film to guarantee Al and Alalloy plating before plating.

The pretreatment technology of current aluminium alloy comprises the following steps: degreasing → matting → leaching zinc → electronickelling → chemical nickel plating, wherein soak zinc step and be mainly double zincate process, because the potential difference between zinc and phosphorus nickel alloy layer is larger, affect bonding force and the protective of nickel dam, twice leaching zinc gained zinc layers can be dissolved in plating solution often at follow-up chemical nickel plating, has a strong impact on bath stability; And the nitric acid cleaning that can use prepare at 1: 1 between twice leaching zinc, easily evaporate into acid mist in process of production, environmental hazard is large.In addition the method for twice leaching zinc has many shortcomings: 1, zinc-impregnating layer has pollution to chemical nickel-plating solution.2, in the corrosive atmosphere of humidity, zinc constitutes the anode of corrosion cell relative to nickel coating, and zinc layers will be subject to lateral encroaching, finally causes nickel dam to peel off.3, between twice leaching zinc, one more nitric acid moves back zinc operation, contaminate environment.4, the commodity leaching zinc liquid of exploitation at present contains prussiate, and operational danger is large, does not more meet environmental requirement.Therefore, be in fact necessary to propose a kind of aluminum alloy activated liquid, be not only independent of each other but also less contaminate environment with follow-up chemical nickel plating operation.

Summary of the invention

The object of the invention is to propose a kind of aluminum alloy nickel plated pre-treatment activation solution compound method used for electronic device, the activation solution of the method preparation, by the adjustment to component, overcomes defect of the prior art, avoid environmental pollution, and activation effect is good.

For reaching this object, the present invention by the following technical solutions:

A kind of aluminum alloy nickel plated pre-treatment activation solution compound method used for electronic device, consisting of of this activation solution: single nickel salt 52-56g/L, sodium phosphate 18-22g/L, citric acid 22-26g/L, ammonium sulfate 15-19g/L, primary zinc phosphate 12-16g/L, zinc oxide 6-8g/L, sodium hydroxide 65-75g/L, iron protochloride 6-10g/L, Seignette salt 10-14g/L, surplus is water; Described compound method is:

1) first by sodium hydroxide water dissolution, then add wherein by zinc oxide, limit edged stirs, and adds primary zinc phosphate after all dissolving, and then stirs 8-12 minute;

2) in another container, add suitable quantity of water, add single nickel salt, sodium phosphate, citric acid, ammonium sulfate, iron protochloride and Seignette salt successively, stir and make it even in 8-12 minute;

3) by the 2nd) solution of step adds the 1st) in the solution of step, then add remaining water constant volume; After filtration.

The present invention has following beneficial effect:

Activation solution of the present invention processes aluminium alloy, reduce the potential difference of active layer and coating, improve the activity of aluminum alloy surface, the meagre nickel with coated metal growth activity can be formed in aluminum alloy surface used for electronic device, there is good effect to follow-up chemical nickel plating, binding force of cladding material and solidity to corrosion can be improved, the pollution to plating solution can be decreased again simultaneously, improve bonding force and the protective of coating, extend chemical nickel-plating solution working life.

Embodiment

Embodiment one

A kind of aluminum alloy nickel plated pre-treatment activation solution compound method used for electronic device, consisting of of this activation solution: single nickel salt 52g/L, sodium phosphate 22g/L, citric acid 22g/L, ammonium sulfate 19g/L, primary zinc phosphate 12g/L, zinc oxide 8g/L, sodium hydroxide 65g/L, iron protochloride 10g/L, Seignette salt 10g/L, surplus is water; Described compound method is:

1) first by sodium hydroxide water dissolution, then add wherein by zinc oxide, limit edged stirs, and adds primary zinc phosphate after all dissolving, and then stirs 8 minutes;

2) in another container, add suitable quantity of water, add single nickel salt, sodium phosphate, citric acid, ammonium sulfate, iron protochloride and Seignette salt successively, stir and make it even in 8 minutes;

3) by the 2nd) solution of step adds the 1st) in the solution of step, then add remaining water constant volume; After filtration.

Embodiment two

A kind of aluminum alloy nickel plated pre-treatment activation solution compound method used for electronic device, consisting of of this activation solution: single nickel salt 56g/L, sodium phosphate 18g/L, citric acid 26g/L, ammonium sulfate 15g/L, primary zinc phosphate 16g/L, zinc oxide 6g/L, sodium hydroxide 75g/L, iron protochloride 6g/L, Seignette salt 14g/L, surplus is water; Described compound method is:

1) first by sodium hydroxide water dissolution, then add wherein by zinc oxide, limit edged stirs, and adds primary zinc phosphate after all dissolving, and then stirs 12 minutes;

2) in another container, add suitable quantity of water, add single nickel salt, sodium phosphate, citric acid, ammonium sulfate, iron protochloride and Seignette salt successively, stir and make it even in 12 minutes;

3) by the 2nd) solution of step adds the 1st) in the solution of step, then add remaining water constant volume; After filtration.

Embodiment three

A kind of aluminum alloy nickel plated pre-treatment activation solution compound method used for electronic device, consisting of of this activation solution: single nickel salt 54g/L, sodium phosphate 20g/L, citric acid 24g/L, ammonium sulfate 17g/L, primary zinc phosphate 14g/L, zinc oxide 7g/L, sodium hydroxide 70g/L, iron protochloride 8g/L, Seignette salt 12g/L, surplus is water; Described compound method is:

1) first by sodium hydroxide water dissolution, then add wherein by zinc oxide, limit edged stirs, and adds primary zinc phosphate after all dissolving, and then stirs 10 minutes;

2) in another container, add suitable quantity of water, add single nickel salt, sodium phosphate, citric acid, ammonium sulfate, iron protochloride and Seignette salt successively, stir and make it even in 10 minutes;

3) by the 2nd) solution of step adds the 1st) in the solution of step, then add remaining water constant volume; After filtration.

Claims (1)

1. an aluminum alloy nickel plated pre-treatment activation solution compound method used for electronic device, it is characterized in that, consisting of of this activation solution: single nickel salt 52-56g/L, sodium phosphate 18-22g/L, citric acid 22-26g/L, ammonium sulfate 15-19g/L, primary zinc phosphate 12-16g/L, zinc oxide 6-8g/L, sodium hydroxide 65-75g/L, iron protochloride 6-10g/L, Seignette salt 10-14g/L, surplus is water; Described compound method is:

1) first by sodium hydroxide water dissolution, then add wherein by zinc oxide, limit edged stirs, and adds primary zinc phosphate after all dissolving, and then stirs 8-12 minute;

2) in another container, add suitable quantity of water, add single nickel salt, sodium phosphate, citric acid, ammonium sulfate, iron protochloride and Seignette salt successively, stir and make it even in 8-12 minute;

3) by the 2nd) solution of step adds the 1st) in the solution of step, then add remaining water constant volume; After filtration.