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into account the individual characteristics of the mechanical processing mode [2]. Therefore, it is necessary
to study in details the design features of tools intended for composite materials processing, the methods to
machine various types of composites, the properties and tool materials specifications, as well.
Manufacturing of the composite products of various configurations can be produced by the blade
cutting:
1) Conventional turning (mechanical blank deformation by compressing and tensing [4] and
technological filling (impregnating liquid technical medium, followed by its solidification [16].
2) Milling as one of common operational process [7 – 13].
3) Drilling [18].
4) Abrasive methods [19].
In dependence of the type of material and reinforcing elements content the various processing tools
are used [4, 5]: for PCM containing fillers of low hardness, the special processing techniques for these tools
are used, to say, the cutting angle depend on the mechanical properties of materials; fibreglasses for
processing ceramic-based or abrasive tools; the diamond-based tools or equipped with hard alloy and laser
processing techniques are used to process composite materials containing aramid fibers. In the work the
author [16] suggested to increase PCM machining productivity by increasing the cross section of the removal
layer, using broad cutting method (MBC). As a result, the method provides high quality of machined
surfaces. It means that when applying wide blade profile the products are machined by the main cutting edge
to achieve a low surface roughness degree. This method application is efficient for the turning operation,
MBC milling.
It is worth mentioning about of PCM high-speed turning that allows to cut polymer composites at the
rotational speeds of the machine spindle (from 225 to 18,000 min-1) and at ultra-high cutting speeds there
was a significant reduction of the material destruction [17].
Having specific characteristics, the composites are the structural materials when being milled
demonstrate a number of unique features quite different from similar metal milling process. The authors [5 –
13] pay great attention to the research connected with the milling tools for composite materials machining.
The authors designed various constructive prefabricated cutter structures for composite materials processing.
For example, Fig. 3 presents the milling cutter of a single universal body with the slots to assemble the
inserts of designated technological purposes, to fasten cutting elements on the register in two perpendicular
planes [14, 15]. The advantages of these prefabricated milling cutters are: structural and tool materials
saving; the possibility, using a single body and different inserts, to process the surfaces of various
configuration by choosing the appropriate tool material, brands geometric and dimensional parameters of the
tool to decrease the downtime spent for tool readjusting and replacing if the tool loses cutting ability. It
should notice that the single design base of inserts increase the reliability and accuracy of the tool entirely.
а)
b)
Fig. 3 Mills assemblies for composite materials processing:
a) with a spring-loaded pins (Patent RF № 2004109804/02);
b) with pins, bolt fixed (Patent RF № 2002117387/02)
Today, in the intensively developing world, every year there are developed more advanced, accurate
productive designs of the milling tools for composite materials processing. The tool configurations are
numerous and varied. Therefore, it is necessary to study in details all existing developments in the milling, to
identify the most promising and progressive tool design, which has the best quality and productivity
specifications.
When the composite materials are drilled, the defects in entering and leaving openings often are
observed due to the drill impact on the workpiece. In order to minimize defects many companies offer a
special drill designs. It is also possible to stabilize the drilling process, to improve cutting process in
polymeric composite materials drilling.