Phosphating and blackening (oxidation treatment) are two common metal surface treatment processes, mainly used to improve the corrosion resistance and surface hardness of metals. Here are the differences between the two processes:
Phosphating
Principle:
Phosphating is to react the metal surface with a phosphate solution to form a layer of water-insoluble phosphate film.
Steps:
Cleaning: Remove oil stains, oxides, etc. from the metal surface.
Pickling: Use an acidic solution to remove surface oxides to expose fresh metal.
Phosphating: Immerse the metal in a phosphate solution to form a phosphate film.
Water washing: Remove residual phosphate solution.
Drying: Drying treatment to complete the phosphating process.
Advantages:
Enhance corrosion resistance.
Improve coating adhesion.
Improve lubrication performance.
Form a uniform and dense protective film.
Applications:
Auto parts.
Household appliance housing.
Industrial machinery.
Metal coating pretreatment.
Blackening (oxidation treatment)
Principle:
Blackening (oxidation treatment) is to form an oxide film (usually a black iron oxide film) on the metal surface by chemical oxidation.
Steps:
Cleaning: Remove oil, oxides, etc. from the metal surface.
Pickling: Use acidic solution to remove surface oxides to expose fresh metal.
Blackening treatment: Immerse the metal in an oxidizing solution to form a black oxide film.
Water washing: Remove residual oxidizing solution.
Drying and anti-rust treatment: Apply anti-rust oil or anti-rust wax after drying to increase anti-rust performance.
Advantages:
Enhance anti-corrosion performance.
Improve surface aesthetics.
Provide certain wear resistance.
The treatment process is relatively simple.
Applications:
Tools, hardware.
Machinery parts.
Firearms, military equipment.
Decorative parts.
Phosphating treatment is mainly used for surface treatment of steel and its alloy materials. The following are common application materials and products for phosphate treatment:
Material:
Carbon steel:
Carbon steel is the most common phosphated material. The phosphated layer can effectively prevent rust and corrosion and improve surface hardness and wear resistance.
Low-alloy steel:
After phosphating treatment of low alloy steel, its anti-corrosion performance and coating adhesion can be significantly improved.
cast iron:
Phosphating can be used on cast iron parts to provide rust protection and a coating base.
Zinc, aluminum and other metals:
Although less common than steel, phosphating can also be used on metals such as zinc and aluminum to improve their corrosion resistance.
product:
car parts:
Including body, chassis, engine parts, etc., phosphate treatment can provide anti-rust protection and coating foundation.
Appliance housings:
Such as refrigerators, washing machines, air conditioners, etc., phosphating treatment improves the adhesion and durability of the coating.
Construction hardware:
Phosphating treatment for door and window accessories, locks, etc. can extend their service life and enhance corrosion resistance.
Industrial machinery parts:
Such as gears, bearings, fasteners, etc., phosphate treatment can improve their wear resistance and anti-corrosion properties.
Pipes and steel structures:
Industrial pipes, steel structures, etc. Phosphating provides excellent corrosion protection.
Tools and Hardware:
Such as screws, bolts, hand tools, etc., phosphate treatment can improve their surface hardness and service life.
Purpose and effect of blackening treatment:
Anti-corrosion: Blackening treatment forms an oxide film on the metal surface, providing a certain degree of anti-corrosion protection.
Improve wear resistance: The surface after blackening treatment has high wear resistance and is suitable for parts with frequent contact and friction.
Reduce reflection: The black oxide film can reduce the reflection of the surface and is suitable for military and tactical equipment.
Beautiful decoration: The surface after blackening treatment has a uniform black appearance, which improves the aesthetics of the product.
Increase surface hardness: Blackening treatment can improve the hardness of the metal surface to a certain extent and increase its durability.
We will choose the appropriate surface treatment for all our products. If you have any metal casting needs, please feel free to contact me at joy@welongpost.com