Brinell Hardness Number
Description
BHN or Brinell Number is the numerical value assigned to the hardness of metals and alloys. The test is to determine the hardness of a metal by pressing a steel ball of a standard size into the metal using a standard force.
The standard format for specifying tests can be seen in the example “HBW 10/3000”. “HBW” means that a tungsten carbide (from the chemical symbol for tungsten) ball indenter was used, as opposed to “HBS”, which means a hardened steel ball. The “10” is the ball diameter in millimeters. The “3000” is the force in kilograms force.
Variables
BHN | Brinell Hardness Number (kgf/mm2) |
P | applied load (kgf) |
π | pi |
D | diameter of indenter (mm) |
d | diameter of indentation (mm) |