Manufacturing

The uniqueness of Metal-like Ceramic is based on the multi-stage manufacturing process via the precursor route.

In the first process step, a polymer starting material is mixed with different fillers. This mass can then be processed at low cost using proven methods of the polymer industry, such as extrusion or injection molding, and brought into an initial preform. The polymeric material serves as a plastic matrix material for the fillers. The processing methods mentioned above make it possible to produce a high geometric variety of preforms.

During a first temperature step, the polymer matrix is then cross-linked and a so-called green body is created. This green body has a plexiglas-like consistency, which means that a near-net-shape part with a high degree of geometric freedom can be produced from the preform with a minimum of mechanical effort. This not only offers the advantage of easy mechanical machinability, but almost all desired geometries can be produced. In addition, the machining process causes only extremely low tool wear and thus increases the service life of the machines.

Following the near-net-shape forming, the green bodies are ceramized by a pyrolysis step at temperatures above 1000 °C. During this process step there is a low shrinkage of approx. 5-8 %, which is why the green bodies are produced with a corresponding oversize. During the pyrolysis, chemical reactions take place between the polymeric matrix and the fillers, resulting in a complete conversion of the starting materials into ceramic compounds. No residues of the polymeric matrix remain in the material.

As a final process step, the ceramicized components can be subjected to a (usually minimal) finishing treatment. No expensive diamond tools have to be used for this. Due to the moderate hardness compared to conventional technical ceramics, tools and abrasives with CBN can be used. The finished ceramic made of MLC offers a completely new combination of material characteristics, which can be used, for example, as a ceramic roller for precise hybrid bearings or ceramic linear guides.