Black Oxide Finishing
For Midwestern Manufacturing, Tool & Die, Automotive and Stamping Industries
UNICO provides black oxide finishing on a wide variety of parts. We can handle any size or configuration. Parts up to 60 inches long are processed in 1 cycle. Parts up to 100 inches long can be double dipped. (This creates a blur line on the part being processed.) We stand behind our workmanship, with over 95 years of combined processing experience.
What is Black Oxide?
Black oxide is a conversion coating formed by a chemical reaction produced when parts are immersed in the alkaline aqueous salt solution operated at approximately 285 degrees F. The reaction between the iron of the ferrous alloy and the hot oxide bath produces a magnitite (Fe o4) on the actual surface of the part. It is possible to oxidize non-ferrous metals under suitable conditions to form black oxides. It is possible to apply black oxide at room temperature, however it is not possible to achieve all of the benefits available from the “hot” oxide process. The cold black oxide process routinely shows color variation from part to part and the black material frequently rubs off in your hands. The cold process does not meet military or automotive specifications. Therefore, the remainder of this article adresses the “hot” black oxide process.
Why choose Unico?
- We conform to military and industry standards
- Fast turn around time
- Competitive pricing
- Large and small production
- Rack and Barrel processing
- Quick response to customers
UNICO is ready to assist you with your black oxide finishing needs. Contact us now at (262) 782-2223 to get started.
What We Offer
Uniform coating for ferrous metals.
Decorative coatings and corrosion protection.
For moving parts that cannot tolerate the dimensional change of a more corrosion-resistant finish.
An alkaline oxidizing finish for 300 Series corrosion resistant alloys.