High-quality aluminum coils (typically 1xxx, 3xxx, or 5xxx series alloys) are selected based on the intended application.
The coil is unrolled and inspected for defects such as cracks, oxidation, or uneven surfaces.
The aluminum sheet undergoes a multi-step cleaning process to remove grease, dirt, and oxidation.
Chemical treatment (chromate, phosphate, or non-chrome conversion coating) is applied to improve adhesion and corrosion resistance.
Rinsing and drying follow to ensure a clean, reactive surface.
A primer is applied to enhance adhesion between the aluminum surface and the final coating.
The primer layer also provides additional corrosion resistance.
The coated sheet is passed through an oven for curing at high temperatures (typically 200-300°C).
The topcoat is applied using roller coating, ensuring an even and consistent finish.
Types of coatings include:
Polyester (PE): Cost-effective, good gloss, moderate durability.
PVDF (Polyvinylidene Fluoride): Excellent weather resistance and durability.
PU (Polyurethane): Tough, abrasion-resistant coating.
Epoxy: Chemical and corrosion-resistant coating.
Multiple layers may be applied for added durability.
The coated aluminum sheet is cured in an oven at high temperatures (~200-250°C) to solidify the coating and ensure adhesion.
This step enhances the coating’s durability, weather resistance, and mechanical properties.
The sheets are cooled before further processing.
Quality control checks include:
Color consistency
Adhesion strength (cross-cut test)
Thickness measurement
Gloss and surface smoothness
Bending and impact resistance tests
A plastic protective film is applied to prevent scratches during handling and transportation.
The film can be easily removed before installation or use.
Coated aluminum sheets are cut into the required sizes or kept in coil form.
The finished sheets are packed with anti-moisture and anti-scratch materials for safe transportation.
