Electroplating process is the use of electrolysis principle of conductive material on a layer of metal method. Electroplating refers to a surface processing method in which cations of pre-gold-plated genus are deposited on the surface of the base metal by electrolysis in a salt solution containing pre-gold-plated genus and the base metal is plated as the cathode.
The coating performance is different from the base metal and has new characteristics. According to the function of the coating is divided into protective coating, decorative coating and other functional coating.
When electroplating, coating metal or other insoluble materials as the anode, the workpiece to be plated as the cathode, coating metal cation is reduced to form a coating on the surface of the workpiece to be plated. It can enhance the corrosion resistance of metal (coating metal is mostly corrosion-resistant metal), increase hardness, prevent wear, improve electrical conductivity, smoothness, heat resistance and beautiful surface.
2, in addition to the oil
Clean the additional surface, remove the oil, dust, sweat and other substances on the surface of the injection parts, which will directly affect the processing effect of the following process, as well as the electroplating appearance of the surface of the parts
The use of strong acidic solution of ABS plastic B (butadiene) components, so that the surface of parts to form a microscopic rough "dovetail" hole increased the plating surface and parts of the contact area, and on the surface of some OH,-SOH>C=0= polar hydrophilic groups, so that the surface of parts with hydrophilic.
Using the reducibility of the solution, the residual collaterals on the surface of the parts are reduced and removed. The residual collaterals must be neutralized and cleaned if they have adverse effects on the following processes
If the acid is hidden on the surface of the parts and brought into the following process, the parts will not be partially plated (dew plastic)
The catalytic substance colloidal palladium (PD) in the solution is evenly adsorbed in the dovetail hole behind the parts, providing a catalytic center for the subsequent chemical nickel reaction
The colloidal palladium adsorbed on the surface of the parts in the catalytic solution does not have catalytic activity because it is surrounded by divalent tin ions. The divalent tin around palladium needs to be dissolved through the degummed process to make it bare and really have catalytic activity
7, chemical nickel
For the mechanism of chemical nickel, there is no unified understanding, according to the "atomic hydrogen state theory" to explain, in the presence of catalyst occurs
8, pre-nickel plating
The chemical nickel layer is relatively thin (0.2um) and has poor electrical conductivity. Adding a layer of pre-plating nickel on the chemical nickel surface can increase the electrical conductivity of the parts
9. Bright copper
Copper has good ductility, flexibility, the other coefficient of thermal expansion is more approximate to the plastic coating on the surface of parts on a layer of about 15 to 25 um, smooth and flexible copper layer is beneficial to increase the adhesion strength of the part and the whole coating, in part by the external environment temperature changes or shocks can play a role as a buffer, decreasing part damage.
10. Semi-bright nickel
Parts appearance of half light to so called half bright nickel and the coating has good ductility and leveling, a bright nickel layer basically bad sulfur (< 0.005%), the potential is light, bright nickel plating parts on the copper layer to nickel plating on a layer of half light and bright nickel, used parts at the same time has good mechanical properties and corrosion resistance
11. Pearl nickel
The appearance of the pearl bright effect makes the parts look elegant, soft color
12. Nickel seal (microporous nickel)
On the basis of bright nickel solution in the electroplating solution to add some bad conductive fine particles (generally about 0.5um in diameter), in the electroplating process nickel continues to deposit on the parts, at the same time, these particles are also brought into the coating, these particles due to non-conductive particles on the particle is not plated on other coatings, So play winding plating layer formed through later parts nickel layer of discrete holes (commonly known as microporous), at the time of parts subjected to corrosion, it is the presence of these pores increases the exposed area of the nickel layer, good dispersing the corrosion current, make the per unit area of surface corrosion current hit me reduce, corrosion speed decreased, thus avoiding the concentration of strong corrosion depth, Has a very good corrosion resistance effect
13, bright luo
The coating is dazzling silver so that the parts achieve a good decorative effect
14 and under
Remove the parts from the hanger for inspection and packaging.