Electroplating equipment operates on the principle of electrodeposition, where metal ions in a solution are reduced onto a conductive substrate through electrolytic reduction. This process requires:
Author: Anna
Working Principle of Electroplating Equipment
Electroplating equipment operates on the principle of electrodeposition, where metal ions in a solution are reduced onto a conductive substrate through electrolytic reduction. This process requires:
DC Power Supply (rectifier)
Anode (source of metal ions)
Cathode (workpiece to be plated)
Electrolyte (metal-ion solution)
When voltage is applied:
Anode (Positive): Oxidizes and dissolves metal (e.g., Cu → Cu²⁺ + 2e⁻)
Cathode (Negative): Reduces metal ions (e.g., Cu²⁺ + 2e⁻ → Cu)
Metal ions (e.g., Ni²⁺, Au⁺) move toward the cathode through the electrolyte under electric field influence.
Ions gain electrons at the cathode surface, forming a metallic coating (e.g., 0.1–50 μm thick).
Deposition rate follows Faraday’s Law:
| Component | Role |
|---|---|
| Rectifier | Converts AC to DC (typically 1–12V, 0–1000A) with ripple control (<5%) |
| Anode | Soluble (same metal as plating) or insoluble (e.g., titanium baskets) |
| Electrolyte Bath | Contains metal salts (e.g., CuSO₄), acids/bases, and additives (brighteners) |
| Agitation System | Enhances ion flow (mechanical paddles/air bubbling) |
| Filtration | Removes particulates (1–10 μm filters) to prevent roughness |
Current Density (A/dm²): Dictates deposition speed and grain structure
Temperature (20–70°C): Affects ion mobility and bath conductivity
pH (0–14): Influences throwing power (acid baths: high speed; alkaline: uniform coverage)
Pulse Plating: Uses alternating current to refine grain size
Electroless Plating: Auto-catalytic (no external current) for non-conductive substrates