16
6.2.5 When the instrument makes an audible beep, stop rotating the wheel and the instrument
will automatically apply the test force. If the initial manual force applied is too high, the
instrument will continuously beep and will not proceed. In this case, lower the anvil table
and select a new location for the hardness test point and repeat the preloading
procedure.
6.2.6 When loading, dwell and unloading is completed, lower the table to automatically reset
the instrument.
6.2.7 The recommended Dwell times are 10~15 seconds for ferrous metal, 30 seconds for
nonferrous metal, 60 seconds for those hardness value is less than 35HBW.
Average diameter of indentation (d)
Minimum thickness of specimen
Diameter of steel ball
D=1
D=2.5
D=5
D=10
0.2
0.08
0.3
0.18
0.4
0.33
0.5
0.54
0.6
0.8
0.29
0.7
0.4
0.8
0.53
0.9
0.67
1
0.83
1.1
1.02
1.2
1.23
0.58
1.3
1.46
0.69
1.4
1.72
0.8
1.5
2
0.92
1.6
1.05
1.7
1.19
1.8
1.34
1.9
1.5
Содержание OMEGA-HB
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