Options
2008
Conference Paper
Titel
Corrective polishing of complex ceramics geometries
Alternative
Korrigierendes Polieren komplexer Geometrien in Keramik
Abstract
Advanced ceramics are primarily used in adverse environments and applications, due to their high hardness, remarkable corrosion resistance, low thermal expansion, high thermal shock resistance and low weight. Representatives are silicon nitride balls in bearing components and silicon carbide mirrors for astronomical optics devices. Furthermore, these non-oxide ceramics can be used by mold manufacturers for molding complex optics components out of glass. In order to obtain the low roughness requirements of the optical systems, a defect free surface and an accurate form is indispensable. This paper showed the results of scientific studies with the goal of shortening the development of a stable and reproducible polishing process for corrective machining of complex ceramics samples. The transfer was successful by rendering unnecessary intensive preparatory work on polishing strategies and resulted in satisfying overall results with a high and reproducible MRR (material removal rates) and surface quality. In terms of the machine parameters, the eccentric frequency shows only a small impact for the profile formation. However, the eccentric radius, the applied normal force and the relative velocity do have significant impact on the formation of the influence function determining the process efficiency. These technological insights were used to accomplish a first corrective polishing by the zonal process. The ongoing research does include the expanding of geometrical complexity up to free formed surfaces of various advanced ceramics. The results will be presented in future publications.