Analysis of Explosive Load on Wire Generated by Discharge of Wire EDM

Abstract

In this study, the explosive load acting on the wire surface generated by discharge on the rough cut and the finish cut of wire EDM is investigated. The hydrodynamic explosion process in the water-filled gap is numerically analyzed using adiabatic bubble expansion model, and the impulsive load of each discharge acting on the wire surface is calculated. The distribution function of the discharge number on the wire surface is derived and the total load acting on the wire generated by continuous discharges is estimated. Wire deflection caused by the total load is compared with the experimentally obtained wire deflection and also with the wire deflection derived from the simple model, assuming that the impulsive load of each discharge is constant and acts normally on the wire surface. Results show that; 1) the impulsive load vector on the wire surface of each discharge is not normal to the wire surface, 2) the value of impulsive load by each discharge depends on the slammed depth and the location on the wire surface and 3) the results of analysis are able to explain the influence of the skimmed depth on the wire deflection of the finish cut and the rough cut.