Electro-deposited Rhodium (Rh) Plating

Optiforms Electro-deposited Rhodium (Rh) platings protect and increase the reflectivity of electroformed nickel substrates.

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Optiforms Electro-deposited Rhodium (Rh) Platings

For years rhodium has been the standard electro-deposited plating applied over electroformed nickel reflectors and components due to its hard, durable, and inert properties. When used in reflective applications this precious metal ranges from near 70% in the near ultraviolet to over 80% in the near-infrared.

Of all the platinum family metals, rhodium is considered to be the most resistant to corrosion and tarnish. As a protective coating, rhodium virtually eliminates any chance of surface discoloration even when exposed to extreme environmental conditions under normal temperatures. For these reasons, rhodium is beneficial as a finished plating over electroformed nickel when used in conditions consisting of heavy humidity, salt exposure, corrosives, as well as many other extreme environments.

Substrate Type: Metallic, typically nickel, or substrates plated with nickel overplate.

Thickness: Typical thickness range of 6-8 µin for increased %R and corrosion resistance.

Size: Ranging from .120" (4mm) to over 20" (508mm)

Geometry: Specializing in complex shapes, deep shapes, where aspect ratio doesn’t permit vacuum coating.

ASTM-B-634 (MIL-R-46085B) 


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