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METALWORKING EQUIPMENT
AND TOOLS
[2]. Processing by towing technology on
the DF-Tools machine provides a uniform
reduction in roughness Ra, Rt and Rmax
on the cutting edge and its rounding,
which allows you to remove stress
concentrators and significantly increase
the feed, for example, during milling. Due
to the smoothing of the chip groove, the
adhesion of the chip decreases (relevant
when machining aluminum and titanium
alloys) and the chip yield on the front
surface is improved (Fig. 5). In this case,
a roughness profile is formed, which
contributes to an increase in the adhesion
of the surface of the tool (substrate) with
a wear-resistant coating. As a result, the a b
strength and power spent on cutting are Fig. 3 General view (a) and working area (b) of the SF 3/105
reduced. The phenomena listed above lathe equipped with pulse PulsFinish® drives
can significantly (up to 1.5 ... 4.0 times)
increase the tool life even without applying a wear-resistant coating [6].
Microgeometry of the cutting edge (rounding radius — degree of sharpness, symmetry
coefficient, edge roughness) is controlled using special microscopes [1, 4, 5], for example,
MikroCAD from LMI (Canada) or EdgeMasterX from Alicona (Austria).
When coating is applied by the PVD method, drops
are inevitably formed on the surface (Fig. 6, a). It
is known that the droplet phase on a wear-resistant
coating enhances friction in the cutting zone and,
a as a result, accelerates the wear of the coating due
to increased heat absorption. After processing coatings
with drops on DF machines, dropping is removed (Fig.
6, b) and the surface roughness is reduced, which is
b guaranteed to increase the resistance of the cutting
Fig. 4 Chipless tap: a) before processing on tool.
the SF lathe; b) after processing on the SF Among the tools for shaping by plastic deformation
lathe can be attributed punches of various shapes, sizes and
purposes, which during the manufacturing process after heat treatment operations are usually
subjected to grinding. When processing with abrasive wheels or tapes, the appearance of
roughness on the surfaces of stupas and troughs is characteristic. Traditional processing (manual
polishing or processing using polishing tapes) does not provide a mirror surface and at the
same time are very laborious. In turn, after processing using towing technology, the roughness
profile is smoothed out and the roughness height decreases to Ra 0.02 μm, which increases
the resistance of punches and improves the quality of the pressed products
(Fig. 7).
The surface roughness is of great
importance in arthroplasty, where artificial tibia,
femur and knee joints made of CoCr of various
stainless alloys, ceramics and plastics are used. a
After casting (sintering) and grinding, there are linear
and cross scratches on the surfaces of the implants (Fig.
8, a), which is unacceptable for medical requirements.
Currently, even ceramic implant surfaces are
required to ensure a roughness Ra of less than
0.02 μm (Fig. 8, b). For these purposes, towing b
polishing technology and special abrasive media are
used. A feature of the processing is the use of inclined Fig. 5. The end spherical carbide mill and
holders. its micrograph cutting edge: a) after grinding
Among the products processed on machines of the / sharpening; b) after processing on the
DF series, one can also include body parts, bushings, machine DF -Tools.

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