Tin-Zinc and Other Glenair Material Innovations

Corrosion Protection Treatments Fighting corrosion is a perennial struggle in electrical interconnect systems. Glenair has developed a broad range of technologies and techniques to win the battle in even the harshest application environments. Our objective is always to build parts which meet industry standards and provide years of service. Corrosion-proof composite thermoplastic solutions, austenitic stainless steels, and durable finish platings are at the forefront of our efforts to solve corrosion problems before they can affect the safe operation of high-reliability interconnect systems. Plating is the protective coating of materials, or combinations of materials subject to corrosion, with electro- and electroless- deposited metals and other substances. Certain plating systems, such as Nickel-fluorocarbon polymer, function as a cathodic barrier finish to protect vulnerable substrate materials. As long as the protective coating is unbroken, corrosion is held at bay. In real world applications however, parts get nicked, scratched and worn with use. The best plating systems therefore are “sacrificial,” meaning they halt corrosion by giving up their metals to interfere with the ionic current flow that would otherwise rust the part needing protection. Sacrificial plating systems continue to provide both corrosion protection and conductivity even when scratched or worn- down to the base material (typically aluminum alloy). Because of its conductive and corrosion resistant qualities, electroplated cadmium has historically been applied to interconnect components on commercial and military land, sea and air systems. Cadmium provides up to 1000 hours of sacrificial corrosion protection and excellent lubricity and resistance to galling for threaded applications. Cadmium, a chemical element with the symbol Cd and atomic number 48, is a silver-white metal with a melting temperature of 321°C. When heated above this temperature, for example in a vehicle fire, cadmium oxide fumes may be emitted. These fumes are considered

Connectors and accessories for mission-critical applications are subject

to rigorous salt spray testing to ensure reliable performance in harsh environments

to be dangerous to the environment and human health, which is why industry research and development has focused on finding a suitable replacement for Cadmium-based plating systems. While the reduction and eventual elimination of cadmium is a laudable goal, replacement materials must deliver equal or better levels of performance to be qualified by the DLA and other controlling agencies.

Cd 112.441 867.8 Cadmium

On the cover: Cassiterite (SnO 2 ) with muscovite (mica) crystals. Cassiterite is a tin oxide mineral, and is the most important source of tin ore.

Source: CarlesMillan, from Wikimedia Commons. Distributed under the Creative Commons Attribution-Share Alike 3.0 Unported license. The photo subject has been clipped from its background.

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QwikConnect • April 2023