17. Glossary

Activation — Surface treatment immediately before plating intended to remove/disrupt oxide and expose active metal.

Ampere-hour (Ah) — One ampere flowing for one hour; a useful measure of bath electrical throughput.

Anode — Positive electrode in the plating cell; nickel anodes commonly replenish nickel to the process.

Burning — Dark, rough, powdery, or otherwise defective deposit often associated with excessive local current density or inadequate mass transfer.

Cathode — Negative electrode; the workpiece being plated.

Cathode efficiency — Fraction of electrical current effectively contributing to desired metal deposition.

Current density — Electrical current divided by plated surface area.

Degreasing — Removal of oils and organic soils before plating.

Deposit — The plated metallic coating.

Drag-in — Solution carried into a tank from the previous process stage.

Drag-out — Process solution carried out of a tank on parts/racks.

Hull cell — Small test cell that produces a range of current densities across one panel.

Nickel strike — Specialized thin nickel deposit used to promote adhesion on selected difficult/passive substrates.

Passivation — Formation of a relatively unreactive surface film that can interfere with plating adhesion.

pH — Measure of acidity/alkalinity used as an operating control variable.

Pitting — Small holes/depressions in the deposit often associated with gas, contamination, particles, or wetting problems.

Rack — Conductive fixture that supports parts and carries current.

Rectifier — Direct-current power supply used for electroplating.

Satin nickel — Nickel finish intentionally controlled for lower gloss/soft appearance.

Throwing power — Ability of a plating system to distribute deposit into areas receiving different current densities.

Water-break test — Cleanliness test in which water should form a continuous film rather than bead or retract.