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Pencil hardness experiment, using graphite pencils with different hardness values to evaluate coating hardness.The precise design ensures that the cylindrical pencil lead can maintain a constant 45 ° angle and a fixed pressure.The pencil with the minimum hardness value that can leave marks on the coating can determine the hardness level of the coating.

 

GB/T 6739

ISO 15184

 

 

Pencil Hardness Tester, 13 Chinese pencils, balance pads, user manual