Certified by JPIA these pencils are made from graphite
ASTM D3363
Select your model
Features
For the pencil hardness test, pencils of increasing hardness values are moved over the surface in a precisely defined way until one lead damages the surface. Surface Hardness is defined by the hardest pencil grade which just fails to damage the surface.
Tests coatings for hardness and scratch and wear resistance
Determines wear factor, related to hardness of pencil used
The pressure or weight applied relates to pencil lead crushing and therefore can be used for vertical coating evaluation to achieve repeatable results.
For the pencil hardness test, reference ASTM D3363, pencils of increasing hardness values are moved over the surface in a precisely defined way until one lead damages the surface. Surface Hardness is defined by the hardest pencil grade which just fails to damage the surface.
Observe the pencil track. Sufficient pressure must have been applied either to cut or damage the coating or to crush the lead pencil point.
If neither coating damage or pencil point crushing is observed, repeat the test until a definite observation is made.
If scratching or damage of the surface occurs, proceed with the next softer pencil grade and repeat the testing process until a pencil lead grade is found which crushes and does not damage the coating.
If crushing of the hardest lead should occur, the coating is therefore extremely hard and is beyond the measuring range of this test.