Carbide production / blanks

Powder preparation

Due to its high melting point tungsten carbide (WC) can only be produced through sintering when needed
for technically sophisticated applications. For this purpose, the powder consisting of the tungsten carbide, The cobalt binder (Co) and sometimes additional alloys, is mixed, milled and spray-dried.
This process results in a spray-dried granulate which can easily be used for production, since its chemical and physical properties have already been adapted to the final carbide specification (e.g. WC grain size).
 

Manufacture and machining of blanks

By applying pressure the carbide powder is converted into a blank. The material will receive its near net
shape through the application of traditional machining methods (sawing, drilling, milling, turning), so that
extended machining of the sintered carbide blank is no longer necessary. The density of the blank is
approx. 50% of the sintered carbide‘s density which leads to an approx. 20% shrinkage in length.
 

Sintering

The sintering process converts the blank into a homogeneous piece of carbide with a high degree of
hardness. When sintering hard metal (usually at a temperature of approx. 1400°C), this process is called
liquid phase sintering. In this case, the binder (e.g. cobalt) melts and wets the WC hard material particles.
After sintering, the density of the carbide is almost, or even precisely, the same as the theoretical density.
Any residual porosity which occurs after the sintering procedure may be removed through an ensuing
HIP process.
 

Grinding

CNC external and internal cylindrical grinding
Face and parallel lapping
CNC surface and profile grinding
CNC 5-zxes-grinding
Precision center-less grinding
 

Coatings / surface treatment

Our coating competence covers classic hard material coatings and functional tailor-made coatings
for specific customer applications. For the production of coatings we apply CVD, PVD and galvanic
processes. Special surface treatments are mainly applied to improve brazing properties.
 

Composite parts

For several applications it does not make sense to manufacture the entire component in hard metal.
The use of hard metal is limited to the area in which wear occurs. Materials with suitable wear resistance
are used for the carrier tool; they are easier to machine than carbide. For the combination of
carbide with other materials, numerous tried and tested technologies are applied.
Examples: brazing, gluing, clamping, connections with screws and shrinking.
 

Erosion

Carbide treatment by means of spark erosion meets the highest technological standards. Wire erosion
and cavity sinking by EDM additionally guarantee high precision. Long-standing experience combined
with carbide grades that are specially adapted for erosion guarantee optimum machining results.
 

Control

The control of finished components is part of our certified quality management system. This control is
carried out by qualified staff, mainly on computer-controlled measuring machines. Control records are
archived for 10 years. Upon request the customer can view the quality management records which are
relevant for him.