Black Oxide Coating * RoHS Compliant *
Black Oxide, Blackening, Oxidizing, Oxiding, Black Passivating, Gun Bluing . . . these terms all refer to the process of forming a black iron oxide on the surface of ferrous metals.
The black oxide process is a chemical conversion coating. This means that the black oxide is not deposited on the surface of the substrate like nickel or zinc electroplating. Instead, the black oxide coating is produced by a chemical reaction between the iron on the surface of the ferrous metal and the oxidizing salts present in the black oxide solution. These oxidizing salts include penetrates, catalysts, activators and proprietary additives which all take part in the chemical reaction. The result of this chemical reaction is the formation of black iron oxide, magnetite (Fe3O4), on the surface of the metal being coated. Black oxide has a range of unique properties and benefits that can be applied to a variety of industries.
Ampere Metal Finishing Facilities
Ampere Metal Finishing uses a hot alkaline aqueous black oxide process. Over the years, we have developed a unique blackening process which produces a high quality black oxide coating that complies with automotive, aerospace, and military specifications.
Specializing in black oxide coatings on steel, iron and stainless steel alloys, the company services large and small production runs in rack, barrel and basket work.
Our 20,000 square foot facilities includes one of the largest black oxide lines in Canada. Our 15 feet long by 2 feet wide by 40 inches deep processing tanks, along with a two ton lifting capacity allows Ampere Metal Finishing to process those heavy, oversized parts that most metal finishing shops are unable to handle.
For your bulk processing requirements, our black oxide barrel line, with a two hundred pound load capacity, allows us to provide you with a quality job and a fast delivery time.
Black Oxide on Stainless Steel * RoHS Compliant *
Black oxide can also be applied to stainless steel alloys. Blackening of stainless steel is more difficult than blackening steel alloys. It requires a separate and specialized process, which is not offered by all black oxide finishers. When processed correctly, black oxide on stainless steel produces a deep black finish that doesn't wipe off and is visually appealing.
Ampere Metal Finishing's Stainless Steel Line consists of 45" x 30" x 30" deep tanks and a lifting capacity of one ton. We have many years of experience applying black oxide on stainless steel and our process produces a quality black oxide product.
Supplementary Post Treatments
Applying a supplementary post treatment after the black oxide finish is commonly used to increase the corrosion protection properties of black oxide coatings. Alone, black oxide offers only a very mild corrosion resistance. A properly applied post treatment, allowing full absorption of the supplementary coating into the pores of the black oxide finish, enhances the corrosion protection to the metal, while producing a deeper black appearance. An appropriate post treatment also increases the resistance to abrasion of the black oxide where break-in of mating parts are required.
Oil post treatments are frequently used after black oxide coating. The oil can be either water-soluble or solvent-based and can be controlled so that a fairly heavy oil film is left on the part or so that the part is virtually dry to the touch. Of course, less oil means less corrosion protection. A clear wax or acrylic may also be used as an alternative, dry to the touch post treatment, where absolutely no oil film is desired.
Post Treatments for Improved Corrosion Resistance!
- Water Soluble Oil (Our default post treatment)
- Water Soluble Light Oil (dry to the touch)
- Dry to Touch Solvent-Based Corrosion Inhibitor
- Water Soluble Wax
- Water Soluble Acrylic
For more information about black oxide post treatments click here.
Black Oxide Specifications
Ampere Metal Finishing certifies our Black Oxide Coatings to a variety of specifications. The following lists some of the more common specifications for Black Oxide. If the particular specification you require is not listed, please contact us for further information.
Black Oxide Specifications
- AMS 2485-H
- ASTM B789
- DX550021
- ES 1-02-02
- ESB-M6P4-A
- ESF-M6P3-A
- ESW-M5A5-B
- GM 4347-M
- ISO 11408-1999
- MIL-DTL-13924-D
- P-586
- PS-1129-J
- XEROX 50-0002/50-0004
For a complete list of all the specifications available click here.
For more information about black oxide click here.
To view the properties and benefits of black oxide click here.
