Manual
12
Material hardness (HV)
Minimum material thickness (µm)
800
100
600
110
300
160
Note: The table only shows the values for the 20 N probe.
Condition of the surface
The applied test force (i.e. the selected UCI probe) must not only match the application but also the
surface quality and roughness of the material. While smooth, homogeneous surfaces with low test loads
can be measured, rougher surfaces and coarse-grained require measurements with high test loads.
However, the surface must always be free of contaminants (oil, dust, etc.) and rust.
Dimensions and weight of the part to be tested
From the above analysis, all probes request coating layer or surface layer less than 1 mm. The hardness
value will change if there is resonance. The highest value of vibration is the elastic oscillation, where
some actions can be made in order to restrain these. To do so the piece has to be put on thicker metal.
Rubber and oil can restrain elastic waves. It is recommended to use pieces that have a thickness o
f 2…3
mm and a size, which is not less than 5 x 5 mm.
Also the weight of the material is important. Depending on the weight certain preparations have to be
made:
Weight
>300 g
100 … 300 g
10 … 100 g
Action
Measurement can be
made under normal
conditions
Use supporting ring
Couple to heavy
component
