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Further processing options

Green and hard machining

Best dimensional accuracy through high-precision machine processing

An employee operates a machine for ceramic hard machining.

Components produced with Bosch Ceramics manufacturing processes already have excellent and suitable accuracy. However, if components with extremely high precision are required, further machining may be necessary. By means of green and hard machining, we can design our components with extreme precision: with fits, tight shape and position tolerances or an outstanding surface quality. If the machining is done on the already sintered product, it is known as hard machining and requires a good knowledge of the tools that can be used. In green machining, the part is not yet sintered and the geometry can still be influenced with simpler tools.

Machining before and after sintering

Ceramic component with a thread and a nut made of metal.

Green machining for more complex geometries in pressed parts

Green machining means changing the component even before sintering. After the master mould process, the geometry can be further adapted. For example, fine bores are produced that would cause high costs in the original mould. In this way, production can be more economical. This makes sense especially for pressed parts, as the pressing tools allow for less complexity than ceramic injection moulding or 3D printing. For optimum flexibility, special geometries can then be produced after pressing, in the so-called green part. We will gladly take over the optimal process design of your component for you.

Hard machining for highest precision and best surfaces

In hard machining, the component is reworked in the sintered state. The ceramic has then already reached its full strength: This makes machining more difficult and can only be realised with specific know-how and suitable process technology. Bosch Ceramics has ultrasonic machining centres for optimum results. The generation of high-frequency vibrations improves the surface quality and protects the tools, which in turn makes manufacturing more economical than with conventional processing machines.

Our portfolio of green and hard coating

Milling, drilling, turning

  • Milling of outer contours and pockets
  • Drilling
  • Turning (green machining only)
  • Thanks to innovative ultrasonic technology, milling and drilling can still be carried out even in the sintered state.


  • Milling-grinding
  • External cylindrical grinding
  • Internal cylindrical grinding
  • Surface grinding, face grinding
  • Grinding is highly flexible and gives external and internal geometries the required tolerances and surfaces.


  • One-sided
  • Two-sided
  • Lapping is used as a gentle process for sharp but burr-free edges.


  • Polishing with cloths
  • Polishing with pastes
  • Diamond abrasive grains
  • The achievable surface roughness is even lower than with lapping.


  • Bores are reworked by means of honing. Tight shape and position tolerances as well as the best surfaces can be produced.
  • Honing with solid grain

Your contact at Bosch Ceramics

We look forward to your enquiry