摘要 |
An improved machining method and electrode for use in the traveling-wire EDM process utilizing an aqueous machining fluid medium which is decomposed by erosive electrical discharges into gaseous oxygen and hydrogen. Breakage of the traveling-wire electrode is reduced or eliminated through the use of an improved electrode element comprising a continuous electrode wire substrate and a layer of a polymeric substance having a temperature of thermal decomposition of 100 DEG to 500 DEG C. attached thereto in a distributed manner such as to partially cover the surface of the substrate. The improved electrode element traveling in machining juxtaposition with the workpiece is subjected to the electrical discharges to cause a thermal decomposition of the polymeric substance to form carbon and to allow the gaseous oxygen and hydrogen at least partially to be chemically combined therewith and to reduce the amount of the oxygen gases in the machining gap which tend to cause a continuous arc discharge or explosion as a cause of the wire breakage. The improved elongate element should preferably contain a hydrogen active catalytic metal, e.g. Li, Cs or Sm, having a spectrographic wavelength of 300 to 600 nm to facilitate chemical reaction of carbon with oxygen and hydrogen in the gap.
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