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carbide grade). Today, the coated IC5005 allows
speed values of up to 600 m/min. In another case,
the milling of martensitic stainless steel during the
same years was performed at about 80 m/min for
IC50M (ISCAR uncoated carbide grade), now 300
m/minis the acceptable value when using IC5500
(ISCAR coated grade).

These impressive numbers provide an excellent
illustration of how coated carbides have allowed
leaps in progress to be made in the area of
cutting speeds.

Coating technology continues to develop in two
principal directions – Chemical Vapor Deposition
(CVD) and Physical Vapor Deposition (PVD).
The main result of progress within the area of
CVD was the introduction of Alumina ceramic
coatings. This allows machining at elevated
speeds due to its excellent temperature isolation
properties, high hardness and chemical stability
at high temperatures.

PVD coatings were introduced during the late
1980s. PVD coatings performed a gigantic step in
overcoming the complex problems that prevented
progress within the field of nanotechnology. PVD
coatings brought a new class of wear-resistant
Nano layered coatings. Such coatings (fig.3) are
a combination of layers having a thickness of up to
50 nm (nanometers) and demonstrate significant
increases in the strength of provided by coatings
when compared to conventional methods.

Modern technology allows both methods – CVD
and PVD – to be combined for insert coatings,
as a means of controlling coating properties.
In particular, ISCAR’s carbide grade DT7150
features a tough substrate and a dual MT CVD
and TiAlN PVD coating. This was originally
developed to improve the productive machining
of special-purpose hard cast iron. Another major
advancement in insert technology relates to
post-coating treatments. For instance, ISCAR
developed SUMOTEC, a treatment method for the
already coated surface of an insert. The advanced
SUMOTEC post-coating technology delivers

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