Aluminium sheet procurement standards

Aluminium sheet procurement standards

1: No cracks, corrosion, cracked edges or diffusion spots are allowed on the surface of the sheet with a thickness greater than 0.6mm.

2: The surface of the plate is allowed to have slight defects such as pressed scratches, metal and non-metal indentations, insertions, scratches, roll marks, pine twig patterns and emulsion marks. However, the depth of the various defects shall not exceed the permissible negative deviation of the thickness of the sheet, and the minimum thickness shall be guaranteed.

3: The total area of air bubbles shall not exceed 100mm2 on each square metre of sheet surface.

4: Craft clad aluminium sheet, exposed parts without cladding and surface bubbles are allowed.

5: The defects of the aluminum sheet are allowed to be inspected and repaired with 400 grit sandpaper, the depth of which shall not exceed the permissible deviation of the thickness; the edges of the sheet shall be cut flush and burr-free.

Inspection items of aluminum sheets:

Surface quality, thickness deviation, width deviation, length deviation, sheet flatness of aluminium sheet products. Corrosion resistance, chemical composition and mechanical properties.

Inspection method:

Surface quality of the product by visual inspection.

Thickness deviation measured with a spiral micrometer.

Width and length deviations measured with a tape measure.

The unevenness of the sheet is visually inspected.

Related technical standards

National standard for aluminium sheet and strip (GB/T 3880-2006), a unified standard applicable to aluminium sheet materials.