Electro discharge machining is a suitable process for nearly any conductive material. A method is given to structure nonconductive materials like structural ceramics by placing an assisting electrode on top of the ceramic. These are typically generated via physical vapour deposition processes. In this paper we show that screen-printing and coating with doctor knife are suitable techniques to apply an assisting electrode made of a conductive lacquer on a ceramic surface. With the used equipment thicknesses of 30 μm for screen-printing and about 350μm for coating with doctor knife were realised. The spark erosive process with this assisting electrode is tested on ZrO_2. The processability is characterised in terms of the removal rate of the ceramic material, the wear rate of the electrode and the wear-removal-ratio. Additionally, we investigated the effect of two different synthetic oils on the process performance. The results showed that the choice of dielectric has a significant influence on the process performance. Changing the dielectric from IME 63 to Ionoplus OH 2753 lead to an increase of the removal rate by a factor of 6.6 and a decrease of the wear-removal ratio by a factor of 7.1.
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