TIN

Capability

Tin Plating

Tin is a white, non-toxic, conductive, solderable deposit valued for its corrosion resistance, its electrical performance, and its ability to be soldered cleanly even after long shelf life. It forms a thin protective oxide layer that shields the substrate from corrosion without compromising conductivity or solder behavior.

Those properties make tin a dominant finish in the electronics, electrical assembly, food processing, and shipping industries, where contact resistance, solderability, food safety, and freedom from toxic chemistries are non-negotiable. The deposit is also soft and malleable enough to form, bend, or deform without cracking the plating.

Solderability

Excellent

Holds after aging & shelf time

Contact Resistance

Low & Stable

For connectors & components

Typical Thickness

2–25 µm

0.0001" to 0.001" per spec

Processing

Rack & Barrel

Both methods available

Two Plating Chemistries

Acid and Alkaline Tin Systems

CMC runs both acid and alkaline tin plating chemistries. The right system depends on substrate, geometry, throughput requirements, and the downstream solderability and finish demands of the part.

Acid Tin

High throughput, fast deposition

Acid tin systems (sulfate or methanesulfonic acid based) deposit quickly at high efficiency, making them the preferred choice for high-volume programs and parts where deposition speed and bright finish are the primary requirements. Common for fasteners, terminals, and bulk hardware.

Alkaline (Stannate)

Uniform coverage, complex geometry

Alkaline tin systems (stannate-based) provide superior throwing power into recesses, internal features, and complex geometries. The preferred choice for parts with deep features or where coverage uniformity matters more than deposition speed, including many electrical and electronic components.

Where Tin Plating Fits

Common Applications

Tin's combination of solderability, low contact resistance, food safety, and corrosion resistance makes it the standard finish across a wide range of industries.

  • Electrical connectors and contacts — terminals, lugs, pins, sockets, and the connector hardware that needs stable contact resistance over service life
  • Bus bars and power distribution hardware — high-current copper bus bars where tin maintains low joint resistance and supports clean soldered connections
  • Battery interconnects — bus bars and tabs in hybrid, EV, and energy storage assemblies that move significant current cycle after cycle
  • Semi-conductor and component leads — solderable preserve coating for electronic component assembly
  • Food processing and shipping — non-toxic, FDA-compatible finish for food-contact hardware, cans, and processing equipment
  • Stampings, screw machine parts, and tubular components — high-volume general industrial hardware where solderability or corrosion resistance is needed
  • Fasteners and fittings — electronics-grade and electrical-assembly fasteners

Finish Options

Matte Tin, Bright Tin, and Whisker Mitigation

Tin is deposited in two common visual finishes. Matte tin is essentially pure tin with no brighteners — softer, more ductile, easier to solder over time, and the modern preference for most electronics applications because of its lower tendency to form tin whiskers. Bright tin uses brightening additives in the bath to produce a shinier deposit, often specified for cosmetic visibility or where mating-surface appearance matters.

Tin whiskers — thin filamentary tin growths that can form spontaneously on plated surfaces over time — are a known concern in electronics, particularly since the industry moved away from tin-lead toward pure tin under RoHS and lead-free directives. Modern process control, sufficient deposit thickness (typically 10 µm or more for high-reliability applications), and where required, post-plating thermal treatments significantly reduce whisker formation. We work with customers' specifications and end-application requirements to recommend the right tin process for whisker-sensitive programs.

Specifications & Standards

Standards We Can Meet

ASTM B545

Standard specification for electrodeposited tin coatings

MIL-T-10727

Military specification for tin plating, electrodeposited or hot-dipped

SAE-AMS-2408

Aerospace material specification for tin plating

ANSI/J-STD-002

Component solderability testing reference

IATF 16949

Automotive quality management process control across all facilities

RoHS, REACH

Lead-free, fully compliant with global electronics and ELV directives

Specifying tin for a part?

Send us a drawing, an electrical or solder ability specification, or a part description. We’ll recommend the right tin chemistry (acid or alkaline), the right finish (matte or bright), and the right processing method for your geometry, your substrate, and the standard your program runs to.