Plating the general quality requirements before plating how?

A: before plating plating must be done without scale, rust, stains, no oil, the surface can be completely wetted by water, do not hang drops.
 Plating plating finished, why use clean water?
A: Because the finished product electroplating bath, the surface and there are plenty of holes adhesion bath, and the bath itself usually has some corrosion. If you do not clean, will cause corrosion coating and the substrate, affecting the product's appearance and protective properties. Therefore, the plating tank shall immediately rinse with water and then dried. 31 Pig iron castings Why difficult than other steel parts plating?
A: Cast iron out parts, which is often uneven and porous surface, and in that the surface will be rough and porous coating. In addition, the surface of the iron, there is also free of graphite, which not only affect the coating and the base metal binding, while there are pores in the case of coating, it becomes a cathode corrosion cell, rapid destruction of the coating metal , pig iron in the graphite, may also have the effect of lowering the hydrogen overvoltage, causing the precipitation in the area of ​​hydrogen is easy to hinder the deposition of the metal, so the cast iron parts difficult than other steel parts plating.
In the cyanide copper plating, free cyanide is insufficient, what should be added? Added cuprous cyanide can do?
A: In the cyanide copper plating, free cyanide is low, add sodium (or potassium). Such as adding cuprous cyanide, then further reduce the free cyanide, copper plating becomes crystal thick and rough.
CuCN +2 NaCN = Na2Cu (CN) 3
in the preparation of copper cyanide sandblasted tungsten target, the powdered cuprous cyanide solution with warm water, then add the plating tank, this operation right? A: right. Because of cuprous cyanide is insoluble in water. Cuprous cyanide should be dissolved sodium (or potassium) a solution of sodium cyanide in an amount of 1.15 times the cuprous cyanide.
In the cyanide copper solution, using air agitation suitable for you?
A: In the cyanide copper solution should not use air agitation. Since carbon dioxide in air with the reaction solution of the alkali carbonate. Excess copper plating carbonate would have an adverse effect. CO2 +2 NaOH = Na2CO3 + H2O
Sulfuric acid copper plating solution, what does it do? Content and low impact on the coating?
A: sulfuric acid copper plating solution There are several effects:
(1) to prevent the formation of copper, cuprous oxide, or hydrolysis of other basic salts precipitate.
(2) reduce the effective concentration of copper ions, the copper plating fine crystal.
(3) the resistance of the solution is reduced to improve the conductivity of the solution, to reduce power consumption.
(4) prevent the high current density plating produce rough or dendritic.
Sulfuric acid bath is generally 60 to 80 g / l, the content is too high or too low are not suitable, it is too much to make the coating brittle, and reduce the solubility of copper sulfate. Too little can cause rough coating, anode passivation solution dispersing ability and reduce other failures.