1. Scope of test:
The scope of the present testing report is to supply details regarding the hardness of different coating products used with the sublimation process using the pencil hardness test (according to UNI EN 13523-4:2001).
2. Date of execution of tests: 04/20/2011
3. Description of samples:
The samples tested are aluminum Qpanels pretreated and powder coated with different
powders which are part of the class 7XX (textured powders with different finish).
4. Testing apparatus:
Testing apparatus complete of :
5. Tests executed:
Before the test the samples have been kept at controlled conditions for 24 hours in a room at (70 ± 2) °F (50 ± 5)% of relative humidity. We then have tested the hardness looking to intentionally scratch the layer of powder coating using pencils with increasing hardness (in order: 2B, B, HB, F, H, 2H, 3H, 4H, 5H, and 6H) following the normative UNI EN 135234:2001. The choice to start from the pencil with hardness 2B is not accidental, but determined the fact that the pencils 6B, 5B, 4B e 3B do not occur any damage to the surface of Decoral powder coating that needs to be tested. The hardness of the powder is determined by the hardness of the pencil which did not mark the layer the powder.
Here below, just as an example, we show some samples after the tests. On samples, we wrote all the codes of the pencil used in the test.
6. CONCLUSIONS:
For the samples “DS 7XX” and “DS 7XX S” it was possible to determine with certain accuracy the value of hardness (these powder coatings have a light texture).
For the remaining samples (DS 7XX H, DS 7XX I e DS 7XX SH) we can confirm that:
– All the used pencils DID NOT make any visible marks.
– The special surface finish, very textured, seams to preserve from scratches the powder coating layer, confirming a much higher hardness.
