Influence of needle pulse shifting on the basis pulse for wire-EDM of hard metals

The needle pulse can be shifted by the modular structure of the process energy source on a basis ignition pulse. In the Paper is presented that one basis pulse in connection with a needle pulse an improved roughness can be achieved. The simulation of the thermal influence of the needle-basis pulse-combination shows the influences of the pre-burning-duration and/or the past-burning-duration on the needle pulse. The result shows that the needle pulse shifts are efficient only in selected time ranges. At REM pictures typical surface textures are shown, which can occur by the needle pulse shift.