Cemented carbide, produced by the powder metallurgical technology consists essentially of tungsten carbide (TC) which is used as the hard material and cobalt (Co) as a binder alloy.

In special grades we use additionally titanium carbide (TiC) and tantalum carbide (TaC). The treated powders are cold isostatically compacted in compacting dies or moulds and presintered. The resulting preforms feature the hardness of chalk and can be turned or ground according to the required parameters. A shrinkage rate of up to 50 % of the volume must be taken into account.

Then the preforms are sintered, recompacted hot isostatically and finally ground with a diamond grinding disk or polished with diamond paste.


Microstructure of VG20

The reduction of the binder content lessens the ultimate bending strength, the impact strength and the tensile strength.
In mainly abrasive conditions we use our grades VG50 and VG20 whereas VN13 is resorted to in cases of high corrosion.
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Microstructure of VG50

The properties of our cemented carbide grades in use

VG50 The outstanding properties are its high wear resistance and its high toughness. The low Co content and the high TC content are the reason for the high wear resistance, whereas the size, the shape and the distribution of the tungsten carbide particles account for the excellent toughness

VG20 This grade which combines a high wear resistance and a still sufficient toughness is mainly used for the production of the locking rings and the blocking rings.

VN13 is more corrosion resistant than the grade VG50, as nickel is used as a binder alloy .