Machinability of Cemented Carbides by EDM

CIRP Cooperative Research Project

Abstract

This paper deals with the machinability of cemented carbides by EDM carried out as a frame work of the CIRP Cooperative Research Project of the Scientific Technical Committee E (Physical and Chemical Machining). The aim of above is to investigate the correlation between the machining parameters and the surface integrity of the machined pieces.
The experiments were carried out by well defined test conditions so as to obtain the comparable test results. And also the workpiece material used were delivered by the Technical Secretarat and the University of Aachen as the standard material from one and same production batch.
In respect to our results following features will be pointed out. Both the minimum depth of micro-cracks and maximum workpiece metal removal rate were obtained at the almost same range of the pulse duration (t_i:3-10μs). This similar tendency was observed also among the results of other participants.
To obtain the sound analysis of the results and to provide the optimum machining conditions further works are still going on with broadened test conditions (different grades or manufacturers of the material, shorter t_i, single discharge method, etc.). All these works will be summerized by Heuvelman, Technical Secretary of the Committee, at 28th CIRP of this year.