The aluminium sheet and coil surface is not allowed to have a crack, corrosion and crack edge, the sheets which is greater than 0.6 mm thick surface diffusion is not permitted in spots.
The surface of the anodised aluminium sheet allows slight scratches, scratches, scratches, roller marks, pine dents and emulsion marks on metal surfaces and nonmetallic implants. However, the depth of various defects shall not exceed the allowable negative deviation of the thickness of the sheet, and to ensure the minimum thickness.
Per square meter aluminum alloy sheet surface, the total area of bubbles should not exceed 100mm2.
Process clad aluminum sheet, with or without exposed parts of the coating and surface bubbles.
Aluminium sheet/ plate defects allow the use of 400 sandpaper for inspection of the grinding, the grinding depth shall not exceed the thickness tolerance; plate edge should be trimmed, no glitches.