Mitutoyo HR-530 Series - Brinell Hardness Test; About the Brinell Hardness Test; Precautions for the Brinell Hardness Test

No. 99MBG518A
A-12
PART A : 4 Hardness Test Methods
4.2
Brinell Hardness Test
4.2.1 About the Brinell Hardness Test
The Brinell hardness is calculated from the test force applied to make a circular indent on the test sur-
face using a carbide ball indenter and from the surface area of the indent. This test is used for testing
large specimens that have coarse particle surfaces in uneven quality, such as castings or forgings.
■Indent of the Brinell hardness test
F
d
1
d
2
h
Indent of the Brinell hardness test
Brinell hardness calculation method
k
F
HBW
=
S
)(
2F
0.102
22
dD
π
=
D
D
-
-
HBW:
Brinell hardness value
D:
Diameter of indenter [mm]
F:
Test force [N]
d:
Mean diameter of indent [mm], d = (d
1
+d
2
) / 2
S:
Indent surface area [mm
2
]
k:
Constant=0.102≈
1
9.80665
4.2.2 Precautions for the Brinell Hardness Test
■Test surface
Thetestsurfaceshouldbeaatsurfaceatarightangletothedirectionofthetestforce.
Forthenishofthetestsurface,performthefollowing:
y To read the diameter of the indent up to 0.05 mm:
Finishbymachiningthatcanmakeasmoothnish,ling,orgrinding.
y To read the diameter of the indent up to 0.01 mm:
Finishusingnegrainsandpaper.