Black passivation is a special passivation process after galvanizing that gives the workpiece a unique appearance and performance by forming a black film layer on the surface of the galvanized layer.
Author: Anna
Black passivation is a special passivation process after galvanizing that gives the workpiece a unique appearance and performance by forming a black film layer on the surface of the galvanized layer. The following are the main advantages of black passivation:
1. Unique appearance
Black or dark grey: The surface of galvanized parts after black passivation appears black or dark grey with a matte or semi-gloss effect and a dignified, low-profile appearance.
Strong decorative: black appearance is suitable for high-end products (such as automobile parts, electronic product shells, optical instruments, etc.), to enhance the aesthetics and added value of the product.
2. Medium corrosion resistance
Anti-corrosion protection: black passivation film layer can improve the corrosion resistance of galvanized parts and extend their service life.
Applicable environment: suitable for moderately corrosive environment (e.g. indoor or mild outdoor environment).
3. Good adhesion
Strong film adhesion: the black passivated film layer is firmly bonded to the galvanized layer and is not easy to come off.
Durability: good stability of the film layer, able to maintain the black appearance for a long time.
4. Reduced light reflection
Low reflectivity: Black passivated surfaces have a low reflectivity and are suitable for applications where light reflection needs to be reduced (e.g. optical instruments, photographic equipment, etc.).
Anti-glare: In bright light environments, the black surface reduces glare and improves the comfort of use.
5. Functional applications
Electromagnetic shielding: black passivation layer has certain electromagnetic shielding performance, suitable for electronic products shell.
Heat resistance: black passivation layer remains stable under high temperature environment, suitable for high temperature applications.
6. Environmental friendliness (chrome-free black passivation)
Chromium-free process: With the improvement of environmental protection requirements, the chromium-free black passivation process is gradually popularized, which reduces the harm to the environment and human body.
Compliance with environmental regulations: Chrome-free black passivation meets the requirements of RoHS, REACH and other environmental regulations.
7. Wide range of applications
Automotive industry: used for automotive interior parts, exterior parts, fasteners, etc.
Electronic products: used for cell phone shells, camera parts, optical instruments, etc.
Architectural hardware: used for high-end door and window fittings, decorative parts, etc.
Industrial equipment: used in equipment that needs to reduce light reflection or has electromagnetic shielding requirements.
8. Enhance the added value of products
High-end feeling: black appearance gives products a high-end, fashionable feeling and enhances market competitiveness.
Customization: Black passivation can meet customers' personalized needs for product appearance.
9. Process Flexibility
Multiple substrates: Black passivation is not only suitable for galvanized parts, but also for other metal substrates (e.g. steel, aluminum alloys, etc.).
Controllable process: By adjusting the composition of the passivation solution and the process parameters, it is possible to obtain black coatings with different shades and properties.
The advantages of black passivation include unique appearance, medium corrosion resistance, good bonding, reduction of light reflection, functional application, environmental friendliness (chrome-free process), a wide range of application areas, and enhanced product value added. These advantages have made black passivation an important surface treatment process to meet the needs of high-end markets in a wide range of applications such as automotive, electronics, architectural hardware and industrial equipment.