Black Oxide Service

Black oxide provides a thin, protective layer on the surface of ferrous metals, enhancing their resistance to corrosion and rust.

Advantages of Black Oxide

Black oxide, also known as blackening or bluing, is a chemical conversion coating used to enhance the corrosion resistance and appearance of ferrous metals.

Key Features

High Corrosion Resistance

Prevention of Hydrogen Embrittlement

Improved Aesthetics

Reduced Light Reflection

Black Oxide Surface Techniques

The following table shows common black oxide finishes. If you have any other alloy requirements, please contact us.

Applicable Materials

Colors

Texture

Thickness

Stainless Steel, Steel, Cast Iron, Invar

Black

Smooth, Matte

0.5 – 2.0 μm

Black Oxide FAQs

How much corrosion protection does black oxide treatment provide to metal parts?

The oxide film formed by black oxide treatment provides a certain degree of corrosion resistance protection. However, its effectiveness depends on the specific conditions of treatment and the type of metal. In extreme corrosive environments, further protective measures may be required.
Does black oxide treatment affect the dimensional accuracy of CNC machined parts?

Black oxide treatment typically only generates an extremely thin oxide film on the metal surface, so its ability to affect dimensional accuracy is very limited.
What are the steps of the black oxide treatment?

- Pickling: Metal parts are immersed in an acidic solution to clean the surface and remove oxides and contaminants. This process is to making sure the surface cleanliness to prepare for further processes.

- Alkaline Cleaning: After pickling, parts are cleaned and neutralized with an alkaline cleaner to ensure no harmful residues remain.

- Black Oxidizing: Cleaned parts are immersed in a black oxide solution that typically contains sodium hydroxide and other compounds, forming a black oxide film.

- Sealing: Optionally, parts are immersed in a sealant to increase corrosion resistance by sealing the oxide film.
What is the main purpose of black oxide treatment?

The main purpose of black oxide treatment is to increase corrosion resistance, reduce reflectivity, provide surface protection, and improve the appearance of metal parts.
Does black oxide treatment after CNC machining affect the heat treatment of parts?

Black oxide treatment does not significantly affect the heat treatment of parts. However, the material of the part and heat resistance level should always be taken in to account before the process.