Dressing of grinding wheels for ultra precision grinding of diffractive structures in tungsten carbide molds

The manufacturing of molds with diffractive structures requires new approaches in terms of grinding wheel geometry and preparation. To be able to manufacture small geometric features such as widths and depths in the micron range on the mold, ideally sharp edged grinding wheels should be used. This paper will present dressing procedures to create sharp edged grinding wheels by using metal alloy blocks. The results and achieved tip radii of the dressed resin bonded and metal bonded fine grained grinding wheels will be presented. Finally, grinding tests of a tungsten carbide mold with a diffractive structure are conducted and the results of the achieved form accuracy and surface roughness are presented