Tech Support
13
Macro
Vickers
Model
No.
900
‐
398
Hardness
Tester
3.5.3
The light source of the micro eyepiece
a.)
The instrument adopts the cold light source for the lighting. The
centrality of the center position of the light source would exert a direct
influence on the quality of the image of the indentation. During
assemblage of the instrument, the position of the center of the light
source is already adjusted, and hence the client does not need to adjust it.
b.)
The light intensity of the light source is regulated by the key
“LIGHT+” or “LIGHT-” on the operational board. The operator
should adjust the light so as to have a soft vision field for the
observation.
3.5.4 The specimen
a) The surface of the specimen must be clean, as the grease or the dirt on the
surface would make the edge of the image of the indentation vague, thus
affecting the precision of the measurement. Please clear the specimen with
alcohol based solution.
b) When thin filaments, thin pieces and small bits are used as the specimens,
the special accessories such as fine wire test table, thin specimen test table,
fork-shape test table and metallurgical equipment can be used. The fine
wire test table, thin specimen test table and fork-shape test table holder
should be used to hold the specimens respectively on the large testing
table for the measurement. If the specimen is too small to be held by the
test table, the specimen should be inlayed and polished for the
measurement.
c) The minimum thickness of the specimen should be more than 10 times the
depth of indentation. Check the backside of the sample for any
deformation caused by the penetration of the diamond. If deformation is
visible, the test is erroneous.
Thickness
—
the thickness of the specimen tested shall
be such that no bulge or other marking showing the effect of
the test force appears on the side of the piece opposite the
indentation. The thickness of the material under test should be
at least ten times the depth of the indentation. This is also to be
used as a
