A micro electrical discharge machining (μEDM) device developed to machine tungsten carbide is presented. The device is down-scaled in its dimensions and integrated in an existing high-precision desktop tool grinding machine. The cylindrical μEDM-electrodes are made of tungsten carbide and have diameters down to 10μm at a length of 100μm. During the μEDM process, the tungsten carbide shaft is mounted in a spindle with an aerostatic bearing, propelled by an air turbine drive. The rotation leads to exceptionally centred holes. The μEDM-source is realized by a low power pulse generator which is mounted on the machine desk. With this μEDM device, a wide range of electro conductive materials can be machined. Furthermore, the entire device is designed to optimize the shape of micro pencil grinding tools by machining a small cavity into the tool tip. The presented μEDM device allows to process micro pencil grinding tools with diameters down to 20μm.
展开▼
