The materials used for manufacturing electroplating bath lining are determined by the nature of the electrolyte (corrosion resistance, temperature resistance, etc.). Commonly used are PVC, polypropylene hard (soft) sheet, titanium plate, lead plate, ceramic, etc. What is the reason for the blackening of the electroplating gold layer?
Electroplating bath: What is the reason for the blackening of the electroplating gold layer?
1. Thickness control of nickel plating layer
The gold plating layer of PCB is generally a very thin layer, which is reflected in the surface problems of gold plating. Many of them are caused by the poor performance of nickel plating. Generally, the thin nickel plating layer will cause the appearance of the product to be white and black. Therefore, this is the first item to be checked by engineering and technical personnel. Generally, it needs to be electroplated to 5 μ Only about the thickness of the nickel layer can solve the problem of white and black appearance.
2. Status of liquid medicine in electroplating nickel cylinder
If the solution of the nickel cylinder is not well maintained for a long time and carbon treatment is not carried out in time, the nickel layer after electroplating will easily produce flaky crystals, resulting in increased hardness and brittleness of the coating, and in serious cases, blackening of the coating will occur. Therefore, engineers and technicians need to carefully check the condition of the liquid medicine in the production line, carry out comparative analysis, and carry out complete carbon treatment in time to restore the activity of the liquid medicine and the cleanness of the electroplating solution.
3. Gold cylinder control
As long as the solution is well filtered and replenished, the pollution degree and stability of the gold tank will be better than that of the nickel tank. However, it is necessary to check whether the addition of the gold bottle supplement is sufficient and excessive, how to control the PH value of the solution, and how to control the conductive salt. If there is no problem in the inspection, use the AA machine to analyze the impurity content in the solution. The liquid state of the liquid storage tank. Check whether the filter cotton core of the gold cylinder has not been replaced for a long time.
Electroplating bath: What are the solutions to blackening of electroplating solution?
1. The pretreatment of special electroplating products must be clean and complete, and some grease and rust should be filtered frequently. Otherwise, excessive deposition will lead to blackening of the electroplating solution and greatly reduce the service life.
2. If necessary, two curing tanks are used for electroplating oxidation. It not only solves the problem of red and gray hanging, but also prolongs the service life of the electroplating solution.
3. Try not to interrupt the production process or complete it at one time, because molecules will pass through each time the electroplating solution is heated, causing unnecessary waste.
4. It is very important to strictly control each inspection point according to the standard operation, especially when heating the electroplating solution. Too high temperature of the electroplating solution will cause red and gray hanging, and too low temperature will cause adhesion or thinning of the plating layer of the electroplating product. Therefore, pay attention to the temperature of electroplating solution at all times.
5. There is a high probability that some small electroplating parts will fall into the electroplating bath, resulting in the loss of effective molecules. So we must fish in time.