Pin Header Plating: Gold vs Tin for Resistance, Durability and Cost

The plating is the real contact surface

Pin stock is usually brass or phosphor bronze with a nickel underplate, then tin or gold. Field failures that appear months later are often a surface film, not a bent pin.

Tin: economical for low-cycle assembly

Tin solders easily and suits appliances, power boards and one-time board-to-board assembly. It oxidizes in air, so high mating cycles or long open exposure will raise contact resistance.

Gold: stable for signals and repeated mating

• Flash gold (~0.05–0.1μm): better cosmetics and short-term oxidation resistance at modest cost.
• Thicker gold (0.3μm+): industrial and telecom interfaces with tens to hundreds of cycles. Thin gold wears through to nickel.
• Gold is not a drop-in for solderability. Selective gold-on-contact / tin-on-solder-tail is common when wave solder is required.

Practical picks

• High current, few cycles: tin with adequate normal force.
• Analog sensors and always-on signals: gold.
• Automotive, outdoor or sulfur-rich plants: do not rely on bare tin-to-tin for life.
• Specify thickness on the drawing, not only “gold plated”.

Junjia can supply tin, gold and selective plating. Qualify contact resistance against real mating cycles and climate, not sample shine.