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METALWORKING EQUIPMENT AND TOOLS
Properties of Spark Plasma Sintered Carbide

In metalworking, a tool is widely used, equipped with
replaceable polyhedral inserts (RPI) from cutting materials.
Requirements of high durability are imposed on RPI, that
is, stable wear resistance in a given time interval. The
most common RPIs are made of sintered hard alloys,
the resistance of which depends on the grain size
of their structure - the smaller the grain, the higher
the hardness and wear resistance while ensuring a
sufficiently high bending strength [1, 2].
An important consequence of the reduction in
grain size is the achievement of special sharpness of the cutting
edges with a rounding radius of less than 2 μm. In addition, with
a decrease in the grain size, the amount of heat that goes into the
chips increases, which reduces its supply to the tool and the work
piece [3]. Spark plasma sintering (SPS) is one of the directions for
creating products with nanoscale "grain size", as
stated in a number of works [4, 5].
Determined the possibility of using
alloys, obtained by SPS, for cutting structural
materials. For this purpose, 6 work pieces with a diameter of
40 and a thickness of 5 mm were sintered from a mixture of
nanopowders, including 94 wt % WC and 6 wt % Co, using
an SPS unit manufactured by FCT Systeme (Germany) in
the temperature range from 1100 to 1500 °C. Other
sintering modes:
a) sintering speed V = 100 °C / min;
b) pressure P = 40 MPa;
c) holding time 2 min.
The characteristics of the materials obtained are
given in [6].
Cutting inserts, the types of which are shown in
Table 1, were cut from the sintered SPS billets on an
AgieCharmilles Cut30P wire EDM machine.

Table 1.
Types of manufactured cutting inserts

№ Sintering Plate type Plate Plate Tool Holder Holder
billet temperature, Standards designation Standards Designation
˚С
1 1100 eplaceable GOST SNMN GOST CSBNR
2 1200 square for "S" 19042-80 1204 08- FR 26611-85 2525M 12
3 1300 mounting (ISO 1832- (chipbreaker)
4 1400 85) С8 – 1226)
5 1500
6 1300 soldered GOST 6739 GOST 2101-0013
25426-90 18879-73

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