Black Oxide Service
SogaWorks offers black oxide finish service to enhance the aesthetic appeal and mildly improve corrosion resistance of your metal parts.
Black Oxide Specification
We provide black oxide services on copper, stainless steel, and steel to increase the corrosion resistance minimize light reflection, and enhance the appearance of your parts.
Materials |
Color |
Visual Appearance |
Stainless stee, Steel |
Black |
Smooth, matte black finish |
|---|
Advantages
- Obtains a improved corrosion resistance
- Enhances the hardness of the outer surface
- Provides an attractive, uniform, matte black finish
Notes
- The finish is generally applicable to ferrous metals , such as ferrous metal
- Black oxide can slightly affect part dimensions
Black Oxide Process
A thin layer of black oxide (Fe3O4) is produced on the surface of ferrous metals like steel and iron by a chemical process called black oxide coating, sometimes referred to as blackening or black passivating (black passivation). This layer provides a characteristic black finish and mild corrosion resistance.
Metal components are immersed in a bath that contains 35–45% sodium hydroxide, an oxidizing agent, and a catalyst in the black oxide process. After that, it is heated to about 130 to 150°C (266 to 302°F). Sodium ferrate is created when the surface is oxidized by this mechanism. The Fe3O4 oxide layer is subsequently formed on the pieces’ surface by reducing this sodium ferrate.
