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Pencil hardness experiment, which evaluates the hardness of coatings using graphite pencils with different hardness values.The precise design ensures that the cylindrical pencil lead can maintain a constant 45 ° angle and a fixed pressure.Includes two additional weights to achieve three types of loads.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 with 3 Loadings, 14 Mitsubishi UNI pencils, balance pads, eraser and pencil sharpener, user manual