ANALYSIS OF 3-DIMENSIONAL TRANSIENT HEAT-CONDUCTION FOR PREDICTING WIRE EROSION IN THE WIRE ELECTRICAL-DISCHARGE MACHINING PROCESS

The three-dimensional transient temperature distribution and crater fo rmation of the wire during a single discharge period in the electrical discharge machining process are determined by an explicit finite-diff erence model. The heat load on the wire is simulated by a variable hea t flux boundary condition that part of the circumference where the dis charge channel interacts with the wire. The heal-flux value is calcula ted from the radius of the time-dependent discharge channel and the in put power. The melting point isotherms, obtained at the end of the dis charge duration, are considered congruent with the crater shape. They are compared qualitatively with cross-sectional micrographs taken from wire samples from the experiments. (C) 1997 Elsevier Science S.A.