Popularize electroplating knowledge

Popularize electroplating knowledge

Mon Aug 08 15:17:25 CST 2022

The five basic elements of electroplating:
1. Cathode: The object to be plated refers to various connector terminals.
2. Anode: If it is a soluble anode, it is the metal to be plated. In the case of insoluble anodes, most of them are precious metals (platinum, iridium oxide).
3. Electroplating potion: electroplating potion containing metal ions to be plated.
4. Electroplating tank: a tank that can bear and store electroplating solution, generally considering factors such as strength, corrosion resistance, and temperature resistance.

5. Rectifier: A device that provides DC power.

 

Purpose of electroplating: In addition to requiring aesthetics, electroplating has different purposes according to various electroplating requirements.
1. Copper plating: used for primer to improve the adhesion and corrosion resistance of the electroplated layer.
2. Nickel plating: used for primer to improve corrosion resistance.
3. Gold plating: improve conductive contact impedance and enhance signal transmission.
4. Palladium nickel plating: improve conductive contact resistance, enhance signal transmission, and have better wear resistance than gold.

5. Tin-lead plating: improve soldering ability

 

Composition of electroplating potion;
1. Pure water: the total impurity should be at least less than 5ppm.
2. Metal salt: provide metal ions to be plated.
3. Anode dissociation aid: to enhance and balance the anode dissociation rate.
4. Conductive salt: improve the conductivity of the potion.
5. Additives: buffering agent, glossing agent, smoothing agent, softening agent, wetting agent, inhibitor.

Electroplating conditions:
1. Current density: the current per unit area of electroplating. Generally, the higher the current density, the thicker the film thickness, but when the current density is too high, the coating will be burnt and rough.
2. Electroplating position: The position of the plated part in the bath, relative to the anode, will affect the film thickness distribution.
3. Stirring conditions: the better the stirring effect, the higher the plating efficiency, there are stirring methods such as air, water flow, and cathode swing.
4. Current waveform: Generally, the better the filtering, the more uniform the coating structure.
5. Plating bath temperature: about 50-60 for gold plating, about 50-60 for nickel plating, about 18-22 for tin-lead plating, and about 45-55 for palladium-nickel plating.
6 PH value of plating solution: gold plating about 4.0~4.8, nickel plating about 3.8~4.4, palladium nickel plating about 8.0~8.5,
7. The specific gravity of the plating solution: Basically, the specific gravity is low, the conductivity of the solution is poor, and the plating efficiency is poor.