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The exceptional quality of electroplated diamond and CBN
tools is primarily determined by the structure of their metal
matrix, which is precipitated in a galvanic bath, and the
technology applied in this process.
Slightly more than half of each individual diamond or CBN
cutting grain is bonded in the metal matrix of the primarily
single-layer coatings. A maximum density (concentration) of
the cutting layer is attained via the adjacent "grain-to-grain"
spatial arrangement of the individual grains and the cutting
edge number (Nges.) is simultaneously determined by the size
of the cutting grain. The resulting topology in the cutting
area enables a high rate of metal removal even when machining
relatively long-chipping materials owing to the large amount
of chip space thus provided.
It is not advisable to machine materials which form chips
that tend to be deformed considerably, thus clogging the chip
space. If a single-layer coating is applied, even complicated
profile tools can be manufactured economically.
The profile and dimensional accuracy of such tools is always
determined by the accuracy of the substrate and by the grain
size of the envelope profile resulting from the overlying
cutting grain.
Undamaged substrates can be recoated when the cutting grain
has been worn off.
The electroplated multi-layer coating, which is comparable
to the abrasive coating of a sintered metal bond, is practical
for machining highly abrasive materials such as Al2O3 or thermosetting
materials with abrasive fillers.
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