Pencil hardness, also known as coating hardness pencil test method. It is a testing method and measurement system for calibrating the hardness of coating films. According to industry standards, the hardness of pencil leads is divided into 13 levels. From the hardest 6H, gradually decrease through 5H, 4H, 3H, 2H, H, then through the moderately soft HB, and finally from B, 2B to the softest 6B. H represents hardness, and B represents blackness. The hardness decreases sequentially from 6H to 6B, and the color of the pencil darkens sequentially. The depth of color is related to the graphite content. The darker the color, the higher the graphite content, and the softer the pencil.

Purpose: To determine the hardness of paint film by plowing the pencil hardness grade of the paint film

Experimental technical features: Hardness is represented by the pencil hardness grade obtained by plowing through the paint film under specified test conditions

Technical parameters:

Execution standard: GB/T6739-86 JISK5401 ASTMD2197

Load capacity: 1000+/-1g

Pencil and sample angle: 45 degrees

Pencil specifications: 6H-6B

Scratch speed: 1mm/s