24
Table for Selection Value 0.102F/D
2
Material
Ball Hardness
0.102F/D
2
<140
10
Steel and Cast Iron
≥
140
30
<35
5
Copper and Cupric Alloys
35~130
10
>130
30
35
2.5
Light Metals and Their Alloys
35~80
5, 10
>80
10
8.1.2
For the following materials there are standard Brinell tests:
Steel:
Typically HBW x | 3000 (x=ball diameter).
For steel, the Brinell method is very important because there is a constant, accurate relation
between the Brinell hardness and the tensile strength (with a ratio of 3.53 for carbon steel,
chromium steel and chromium-manganese steel; for chromium-nickel steel it is 3.33).
Example: 225 HBW x | 3000 e.g. 225 x 3.53 = 794.3 N/mm² (see DIN 50150)
This is the only acceptable method for determining the tensile strength of steel non-
destructively.
However, the Brinell method cannot be used for hardened steel. As there is no diamond
penetrator intended for the Brinell procedure. Tests on treated steel with hardness greater
than 1765 N/mm² is not acceptable.
Soft iron is usually tested with HB x | 3000, although the indentation diameter exceeds 0.6 of
the ball diameter.
Cast iron:
HBW x | 3000. Due to the smaller homogeneity, it is recommended to use the
highest total test load of 29,420 N.
Soft metals:
Typically HBW x | 10 or HBW x | 5; for very soft alloys, however, it is also possible
to use HBW x | 2.5. The fact that it is possible to use different degrees of loading for medium
hardness values might easily cause confusion. Thus, it is important to indicate the test used.
Copper alloys:
For bronze use HBW x | 10 (if it is very hard, use HBW x | 30), and HBW x | 10
or HBW x | 5 for brass. Apart from that, also consider the principles mentioned for soft metals
above. For the following materials there are standard Brinell tests:
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