By Finishing

Black Oxide

Black oxide is a conversion coating process for ferrous metals, achieved through a chemical reaction that forms a layer of magnetite (Fe₃O₄) on the surface. This finish provides a durable, attractive black appearance while offering moderate corrosion resistance and excellent dimensional stability, as it adds negligible thickness to the part.

Product details

Typical Applications:

Precision Components: Ideal for screws, gears, and fasteners where maintaining tight dimensional tolerances is critical, as the coating does not alter part size.
Consumer & Industrial Machinery: Used in appliances, office furniture, and internal machinery parts where a sleek, non-reflective black finish is desired for aesthetics and reduced light glare.
Automotive Interior & Under-hood: Applied to non-critical fasteners and brackets that require a degree of rust protection and a uniform appearance.

Our Process & Customization:
Our black oxide process ensures a consistent, deep black finish with reliable performance. Key service parameters include:

Material Compatibility: Primarily applied to carbon steel and alloy steel fasteners.
Corrosion Protection: Standard finish can be enhanced with a supplemental oil or wax post-dip to improve salt spray resistance (e.g., achieving 24-96 hours per ASTM B117).
Appearance & Consistency: Controlled to produce a uniform black matte surface without buildup or staining, suitable for assembly and aesthetic purposes.

The black oxide finish offers an optimal balance of corrosion protection, dimensional integrity, and a professional appearance for precision screws in a wide range of applications.