Black oxide process suitable for both large, small aluminum-alloy parts

Birchwood Casey has introduced the LUMICLAD™ black oxide process, an in-house method for blackening both large and small aluminum-alloy parts.

The process uses a dip-tank procedure without requiring the use of electrolytic chemicals to form the coating. The 1.5-micron finish adheres tightly to the aluminum substrate with no ruboff. Because the process uses no electrical current, no clamp-on racking is needed.

The nondimensional finish will not shrink hole diameters or add measurable thickness. Part dimensions are maintained without requiring critical surfaces to be undersized to allow for excessively thick coatings.

The process takes 30 min. for most alloys. Using a tank that operates at 70 to 200 degrees F, the process line is designed to run as a self-contained, zero-discharge system. Rinse water is purified and recycled by means of an ion exchange system.