Investigation on Dynamic Gas Bubble Formation by Using a High-Speed-Camera System

摘要

During an electrical discharge a gas bubble occurs around the discharge area. This bubble has an impact on the flushing inside the working gap. Powder suspended dielectrics provide the opportunity to influence the gap width and consequently the flushing conditions, too. This effect amongst others leads to a more stable process and better surfaces in terms of a reduced roughness and smaller heat affected zone. With high speed camera photographs a more detailed view into the process is possible. This paper shows chronological sequences of gas bubble formation in terms of their dilatation and collapse. The corresponding gas bubble volumes and resulting crater diameters are described and discussed in order to increase the fundamental understanding of the process.