Common Problems Of Nickle Electroplating

1, pinhole, pitting and peeling

Continuous electroplating coating has pinhole, pitting and peeling is the most common fault in electroplating, mainly caused by the following reasons.

(1) Improper heat treatment process of continuous Nickle Electroplating

In the process of machining, the parts surface adhesion of anti-rust grease, cutting fluid, mechanical oil, lubricating grease, grinding fluid, release agent and dust, grinding dust mixed together to form a thicker dirt. If the above dirt is not removed before the heat treatment, the quenching and sintering of the solid grease after the removal of oil and rust is difficult to clean, plating when the bubble attached to the coating on the formation of gas retention type pinhole.

(2) Nickle Electroplating plating before the poor treatment

Heat treatment workpiece surface will inevitably adhere to a layer of oil, when the dust fell on the surface, and mixed with grease, a long time is difficult to clean, so that the surface of the workpiece to form an obvious small oil spots, when plating bubble stranded on the formation of pinhole. In addition, the use of mesh belt resistance furnace quenching, the surface of the workpiece oil and dust and other impurities particles mixed together, burning to form stubborn solid grease, nitrate temper, above grease and nitro salt formed stubborn thermal polymer, electroplating, it is difficult to remove the above dirt completely clean, hydrogen bubble easily adhered to the dirt, difficult to discharge, so that the coating produced pinhole and pitting phenomenon, and as the bubble gradually grew up, the coating will automatically burst, resulting in peeling phenomenon.

2, Nickle Electroplating coating peeling off

There are two possible reasons for this type of failure, one is the poor adhesion between the coating and matrix, the other is the brittleness of the nickel plating layer, and the ductility is small.

If the heat treatment is not easy to remove dirt or plating treatment is not complete, dirt inclusions between the substrate and the coating, so that the coating and substrate adhesion is very poor, subsequent assembly processing, prone to peeling off.

When the brightener ratio is improper or the quality is poor, the ph value is too high, the cathode current density is too large and the bath temperature is too low, will cause hydrogen ions in the cathode after the reduction, will be the state of atomic hydrogen infiltration of the matrix metal and coating, so that the toughness of the matrix metal and coating to reduce the phenomenon of hydrogen embrittlement. In addition, when the metal impurities in the nickel plating bath and decomposition products too much, it will also cause the coating "hydrogen embrittlement" phenomenon.

3. Poor corrosion resistance

Because the porosity of nickel electroplating is high, only when the coating thickness is more than 25 microns. Therefore, the thin nickel plating layer can not be used alone as a protective coating, preferably with double layer nickel and multilayer nickel system.

4, Hanging green corrosion

After electroplating, the VCF 1385 Antirust cutting fluid was used to seal the coating, and when the antirust cutting fluid was dry, the bad phenomenon of hanging Green was formed in the product.

5, Neconro Copper

Because of the bright plating nickel liquid plating ability is not as good as cyanide plating dark copper, electroplating after the bright nickel coating in the product hole parts can not completely cover the copper coating, resulting in the product inner hole dew copper color undesirable phenomenon.