Check the surface:
Good panels should have clean and flat surface, there are no bubbles, dots, raised grain or scratch on the aluminum surface.
Check the thickness by slide calliper rule, the tolerance of panel thickness should not exceed 0.1mm, tolerance of aluminum thickness should not exceed 0.01mm
Check core material by eyes, the material color should be average, there are no visible impurity.
Bend the panel directly to check its flexibility. acp has two kinds: unbroken and broken, unbroken is more flexible and more expensive.
The coating is divided into PE and PVDF. PVDF coating has better weather-resistance, and its color is more bright and vivid.
Tolerance of length and width should not exceed 2mm, diagonal tolerance should not exceed 3mm
Try to peel the aluminum skin from the core material, use tensionmeter to test the peeling strength, the peeling strength should not under 5N/mm.