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5 necessary auxiliary machines for electroplating industry

5 necessary auxiliary machines for electroplating industry:

Filter and recycle filter equipment:

In order to ensure electroplating quality, the plating solution is required to filter regularly. While filter is the most commonly used filtration device in the chemical industry, and some kinds of electroplating also required ceaselessly cycling filtration on running. We can select the right filter based on plating situation and electroplating bath size as well as technological requirements.

Plating machine Filter

Plating machine Filter

Cathode moving or agitation device:

Some or most of plating, the cathode shall in condition of moving states, then the operating current can be increased, while bath solution give deserved function (usually brightness and dispersion capacity), and can prevent from cusp, corner gross plated, charred. But some types of plating can use equipment or agitation device to replace cathode moving. Mechanical agitation is a mixer which made of corrosion-resistant material, usually, it is driven by motor, but its speed is can not too high. While air stirring adopts the deoiled compressed air after filtering.

air

Heating or cooling machines:

Because of plating solution working at a certain temperature, so electroplating bath shall be equipped with heating devices. For example, temperature of brightness nickel plating should be maintained at 50 ℃, while chrome plating temperature is 50 ~ 60 ℃, but brightness acidity copper electroplating or brightness silver plating required temperature within 30 ℃. Thus, these requirements shall be met by means of heat exchange machinery. For heating, normally use direct heating method.

Plating bath:

Plating bath must be equipped with accessories including anode and anode or anode baskets or anode hook, electrode rods , power cables, etc..
Most anode basket used titanium as material, a few species electroplating adopt stainless steel or steel.
Electrode rod is conductive rod which used for hanging anode and cathode and also connected to power source. Usually made of copper or brass rod, slightly longer than the plating bath, the diameter size according to the current demand, but the diameter at least more than 5cm.
The key function of power cable is to ensure can go through needed current. The best material is copper plate, also multi-strand cable can be adopted, but cross sectional area requirements must be complied with.

plating bath

Plating bath

Plating hanger:

Hanger is the most important auxiliary tools for electroplating process. It is tool not only to make sure plating workpiece connected with cathode, but also has a direct impact on coating layer distribution and efficiency. Now there are professional hanger suppliers to offer general design hanger and also can customize according to users’ special requirements.

plating hanger

Plating hanger

Factors impact electroplating solution dispersion and coverage capability

Factors impact electroplating solution dispersion and coverage capability:

The advantages and disadvantages of plating solution indicated by dispersion and coverage capability. Dispersion capacity refers solution has capability of uniform distribution in coating thickness, which only shows uniformity coefficient on the surface of plating workpiece. Coverage refers the electroplating solution has capacity of depositing coating film on parts deep hole, concavity surface, also called depth capability. Only stated plating surface concavity surface or deep hole whether has coating deposition or not.

1, Current distribution: When the current through the electrolyte solution, the amount of material deposited on the cathode in direct proportion to the electric quanlity through. Greater current density, the coating film is also the more thicker. Metal deposition on the cathode surface depends on the distribution of electricity in cathode. The electrolyte solution resistance and cathode electrochemical reaction resistance, are two important factors which impact the current distribution in cathode, and one of them play a dominant role.
2, Current efficiency: coating film metal distribution depends on the current distribution, but it does not mean equal to current distribution. Through primary current not only consumed metal ion deposition, but also consumed in hydrogen and other side effects. Current efficiency changes with current density changing.

Affect the distribution of the metal in different parts :
A. Cathode current efficiency with current density change almost no change . Different parts of the cathode plating metal depends directly on how much the size of the current.
B. Cathode current efficiency with the increasing of current density but decrease to improve the dispersion capacity. Where the current density high the low current efficiency, while the low current density the high current efficiency. To make the current density distribution uniform, have to change the dispersion capability of the electrolyte solution.
C. The surface state of organism:
Metal hardly deposited on the unclean cathode surface a uniform coating, or even can not deposite. Since hydrogn overpotential on rough surface less than on smooth surface, then on rough surface the hydrogen is easily to precipitate, so it is difficult to deposit coating film.
D. Cathode current efficiency with the increasing to increase will reduce dispersion capacity. Because of the electrical efficiency is high when the cathode current density high, but the current density low when current low, so the actual current density throughout more uneven, resulting in poor dispersibility .
E. Geometric factors:
Plating tank geometry shape, the shape of the anode and cathode, the two electrodes in the plating tank etc.. geometric arrangement factors can directly affect the distribution of coating .
Explain: All these related with the electrolyte solution dispersion and coverage capability, are not isolated from each other, but actual contacted each other.Factors impact electroplating solution dispersion and coverage capability