hitachi electric discharge machining (edm) wire is especially designed for cutting hard metals using the edm process. featuring superior electric properties, edm wire is the first choice for high-speed machining and cutti......hitachi electric discharge machining (edm) wire is especially designed for cutting hard metals using the edm process. featuring superior electric properties, edm wire is the first choice for high-speed machining and cutting projects requiring surface precision. composition lead and other impurities degrade the performance of electrode wires. we have kept these at a minimum, using closely examined materials to improve electric discharge.