OBTAINING EXTERNAL CYLINDRICAL SURFACES BY ELECTRICAL DISCHARGE MACHINING USING PLATE TYPE TOOL ELECTRODE

Abstract

The electrical discharge machining is a machining method applied when the workpiece material has a high hardness or the shape of the surface to be machined is to complicate to be obtained by a classical machining method. A problem of actual interest is the electrical discharge machining of small diameter external cylindrical surfaces in the case of materials characterized by high hardness. Among the distinct electrical discharge machining processes capable to be used in order to obtain small diameter cylindrical surfaces, a process based on the use of a plate type tool electrode was selected. A full factorial experiment with three independent variables and two experimental levels was designed and materialized to highlight the influence exerted by the pulse on time, pulse off time and peak current intensity on the heights of the cylindrical columns generated by electrical discharge machining. By mathematical processing of the experimental results, power type empirical mathematical models were established. The empirical models confirmed the strong influence exerted by the peak current intensity on the process output parameter.