Transient Response of Wire Vibration System in Wire Electrical Discharge Machining

In this paper, a tool wire vibration system in wire electrical discharge machining (wire-EDM) is identified and primary factors of the wire vibration in real machining are investigated by considering transient response of the tool wire to exciting force caused by a single discharge. The influence of pressure caused by each discharge and the influence of an electrostatic force on wire displacement are investigated under a mechanical model in which the tool electrode is assumed to be a beam under a certain tensile force. The displacement of the wire induced by the electrostatic force was observed as the indicial response to applied stepwise voltage. This displacement by electrostatic force is considered as the initial condition for the impulse response to the following discharge. The wire responds to the impulsive pressure which is generated locally by a discharge. The response in the experiments is corresponding to the impulse response simulated with the beam model of the wire.