Aluminium Alloy Extrusion
Ceram Building Technology carried out tests on various aluminium strip materials to determine their resistance to surface marking.
The following 1000mm x 100mm strip samples were tested:
- GA 0178 Mill Finish (reference sample)
- GA 0178S Ano-Sil Anodised
Each sample, commencing with the mill finish, was horizontally attached to a rigid substrate.
A 120mm x 40mm piece of P40 grade emery paper was placed, abrasive side down, onto the strip material. Lead weights, totalling 2.16kg, were then placed onto the emery paper. A cable, attached at one end to weights and passing over a pulley, was then attached to the emery paper and allowed to pull the emery paper and lead weights laterally across the surface of the strip material.
This procedure was carried out once on the plain mill finish and the damage to the surface assessed visually, at an angle of approximately 45 degrees and a distance of approximately 1 metre.
The anodised sample was then tested in the same way with repeated passes of the emery paper until the damage to the surface was assessed to be similar visually to the reference sample.
The full results for the tests are given in Table 1.
From the results obtained it is clear that the surface texture of the sample or profile of the sample is the major controlling factor to the visual assessment of the damage.
Table 1 Surface Marking Test Results
|Sample Code ||Number of Passes |
|Plain Mill GA 0178 |
|Anodised GA 0178S ||4 |