Manufacturing Insight: Tin vs. Nickel Plating — Corrosion, Solderability, Cost
Choosing between tinned copper (TC) and nickel-plated copper (NPC) isn’t just a price call. It’s a performance decision tied to environment, assembly method, and lifetime. Here’s a practical guide to help you spec the right finish the first time.
The quick take
Tin (TC): Best for easy soldering, good general corrosion resistance, and lower cost.
Nickel (NPC): Best for high temperature, harsh environments, and long-life applications where oxidation control matters.
Corrosion & environment
Tin (TC)
Forms a protective oxide that slows corrosion in most indoor/industrial settings.
Great in humid or moderately salty air when not continuously exposed to splash or chemicals.
Watch out for fretting in high-vibration micro-contacts; pair with proper terminations.
Nickel (NPC)
Dense, tightly adherent layer resists oxidation at elevated temperatures.
Superior in thermal cycling, chemical, and near-engine environments (oils, road salt, heat).
Often chosen where you want stable surface behavior over many years.
Solderability & assembly
Tin (TC)
Excellent solderability with common fluxes; wide process window.
Lower wetting temperatures → faster line speeds and less thermal stress on parts.
Ideal for hand solder, wave, reflow assist leads, and terminals.
Nickel (NPC)
Solderable but not “plug-and-play.” Usually needs nickel-strike compatible fluxes, higher temps, and tighter process control.
Frequently crimped, welded, or screwed instead of soldered—great for crimp terminations and high-temp lugs.
Temperature & electrical performance
Tin (TC): Practical up to about 105–125 °C for many assemblies (check connector spec). Tin oxide grows faster at heat, so long dwell at high temp can increase contact resistance.
Nickel (NPC): Comfortable into 200 °C+ zones (consult spec), with stable contact resistance and oxide behavior under heat.
Cost & availability
Tin (TC): Lower plating cost and broader availability. Strong choice when you need value and solder-ready surfaces.
Nickel (NPC): Higher plating cost; you’re paying for thermal and chemical robustness and lifecycle stability.
When to choose what
Choose Tin (TC) if you need:
Fast, reliable soldering (assembly-friendly).
General-purpose corrosion resistance indoors/industrial.
Lower landed cost and high availability.
Choose Nickel (NPC) if you need:
High-temperature service or thermal cycling stability.
Exposure to chemicals/salt/road grime or engine-bay-adjacent zones.
Long-life terminal integrity with crimp/lug connections and low oxide growth.
How Sark Wire helps
Sark Wire offers Bare, Tinned, and Nickel-Plated Copper from AWG 44 to 1200 MCM. Our experienced engineering teams provide application support to balance ampacity, OD, bend radius, and finish for your environment. To ensure everything meets your spec the first time, we ensure QA you can trust.