Influence of electrode material in micro-EDM drilling of stainless steel and tungsten carbide

Abstract

The aim of this work is to analyse the influence of electrode material in micro-EDM drilling of stainless steel and tungsten carbide metal plates. Brass and tungsten carbide electrodes were selected basing on their different electrical and thermal properties. The experimental campaign was based on the execution of a large number of micro-holes carried out by varying some process parameters, namely peak current, voltage and frequency. Tool wear ratio and material removal rate were assumed as process performance indexes, while diametral overcut and taper rate were considered as geometric indexes. The Analysis of Variance (ANOVA) was applied on the results coming out from the experiments. Moreover, a overall Process Index based on both process parameters and electrode material properties was proposed. This index fits, with a good correlation level, all the process performance and geometric indicators for both the considered workpiece materials. A comparison between the performance measured using stainless steel and tungsten carbide workpieces was also carried out. The results of this experimental research showed that electrical resistivity, thermal conductivity and melting point of both electrode and workpiece materials have a significant effect on the process and geometric performance.

Multifilament carbon fibre tool electrodes in micro EDM—evaluation of process performance based on influence of input parameters

“…x ij y j (3) where N is a number of experiments, in considered case 8 according to Table 3, i is the index from 0 to 3 as in the Formula (1), j represents following runs in the experiments from 1 to 8, x represents following values from the Table 3 Fig. 8 Example of the profile of the hole 3 Fig.…”

“…In many cases to obtain better machining output and lower tool electrode wear new materials are tested [7,11,12,15,17,19,22,26,27]. Usually, in most applications, standard electrodes made of graphite, copper or other metals are considered [3,5]. It is because of their high melting temperature and good thermal and electrical conductivity [3,20].…”

“…Usually, in most applications, standard electrodes made of graphite, copper or other metals are considered [3,5]. It is because of their high melting temperature and good thermal and electrical conductivity [3,20]. Sometimes some changes to the standard process are proposed, like sequential machining using different manufacturing techniques or hybrid processes joining at least two manufacturing techniques simultaneously [4,14,21].…”

Influence of Electrode Material on Surface Roughness during Die-Sinking Electrical Discharge Machining of Inconel 718

“…According to their research, the best result (proportion of removed material to electrode wear) was obtained for the current of 6.5 [A] for a graphite electrode. In [14], the authors examined two electrode materials, brass and tungsten carbide, when machining stainless steel and tungsten carbide, with variable process parameters. As a result of the research, they noticed that the brass electrode wears more than the WC electrode, however, it also removes the workpiece faster, due to higher electrical conductivity.…”

A Simulation Study of Debris Removal Process in Ultrasonic Vibration Assisted Electrical Discharge Machining (EDM) of Deep Holes †

“…The investigation focused on the influence of different electrodes’ materials and process parameters on both the process performance and the dimensional characteristics of the holes. The results showed that electrical resistivity, thermal conductivity, and melting point of both electrode and workpiece materials have a significant effect on the process and geometric performance [ 14 , 15 ]. Bellotti et al investigated the micro-EDM process for drilling small through-holes on Ti-6Al-4V while using brass tubular electrodes.…”