The quality of aluminum coil plate products will directly affect that of their end-products, and surface defects will also cause a lot of trouble for both parties. Attaching high importance to quality proves to be a key feature of excellent aluminum coil plate suppliers. As purchasers, you also need to learn something about quality defects to win in negotiation with your suppliers. Here we share the reasons for surface defects of aluminum coil sheet products.
Embossing Marks
The irregular color difference on the surface of the roll during the rolling process due to the wrinkle of the strip, the broken strip and other reasons.
Scratches
These appear as a bundle of scars on the surface of an aluminum plate.
Cause: The pile of aluminum plates is shifted between layers mechanically or manually.
Edge Warping
After rolling or shearing, the edge of the coil strip is warped.
Corrosion
White or black spots on the surface of an aluminum plate.
Cause: Acid, alkali or water has entered during production, packaging, transportation and storage.
Oil on the Surface
The cooling oil is dirty, and the blowing is weak.
Scratching Marks
It appears as scratches on the surface of the aluminum plate.
Causes: The guide plate or flat roll has protrusions or sticky aluminum; scratches occur during cutting; manual inspection is not carried properly.
Side Bending
The longitudinal sides of plates and strips are in a non-straight state bent to one side.
Causes: The rolling reductions at the two ends of the rolling mill are not the same; the thicknesses of the two sides of the plate and the belt are not the same.
Black Spots
Needle-like black spots on the surface of an aluminum coil plate.
Cause: The furnace fluid is not clean.
The information above includes almost all common defects of aluminum coil plate products and corresponding reasons. We supply 3003 aluminum coil, aluminum coil 5052 h32, 5083, 1050, 1060 etc. Welcome to contact us for more information!