Brinell Hardness of Graphite

The Brinell Hardness of Graphite constant displays the value of the Brinell hardness for graphite (5 BHN). 

Brinell hardness test determines the ability of a metal to resist permanent indentation deformation through the scale of penetration of an indenter that is loaded onto a material sample. Brinell hardness is one of several definitions of hardness for materials science.

The Brinell hardness of graphite is 5 Brinell hardness numbers (BHN). 

Reference

Material Properties (https://material-properties.org/graphite-density-strength-hardness-melting-point/)