Description The Brinell hardness test uses a ball indenter of diameter, D, which is pressed into the surface of the test piece using a prescribed force, F. The time for the initial application of the force is 2 s to 8 s, and the test force is maintained for 10 s to 15 s. The diameter of the indentation, d, is measured after the force has been removed. The Brinell hardness number, HB, is given by: HB = Constant Ă— F / Surface area of indentation
Standard Brinell Scales Hardness scale
Ball diameter, D (mm)
Nominal force, F (N)
HBW 10/3000
10
29420
HBW 10/1500
10
14710
HBW 10/1000
10
9807
HBW 10/500
10
4903
HBW 10/250
10
2452
HBW 10/100
10
980.7
HBW 5/750
5
7355
HBW 5/250
5
2452
HBW 5/125
5
1226
HBW 5/62.5
5
612.9
HBW 5/25
5
245.2
HBW 2.5/187.5
2.5
1839
HBW 2.5/62.5
2.5
612.9
HBW 2.5/31.25
2.5
306.5
HBW 2.5/15.625
2.5
153.2
HBW 2.5/6.25
2.5
61.29
HBW 1/30
1
294.2
HBW 1/10
1
98.07
HBW 1/5
1
49.03
HBW 1/2.5
1
24.52
HBW 1/1
1
9.807
The designation "HBW" specifies the use of a tungsten carbide ball indenter. The designation "HBS" specifies the use of a hardened steel ball indenter but is now deleted from standards. It should be noted that measurements of HBW and HBS on the same sample may differ in value due to differences in the tribological characteristics of the indenter-specimen interface.
Standards BS EN ISO 65061:2005,
Metallic materials. Brinell hardness test. Test method