a b s t r a c tIn the present study, the temperature distribution on the surface of workpiece and tool during a single discharge in the electrical discharge machining process has been simulated using ABAQUS code finite element software. The temperature dependency of material properties and the expanding of plasma channel radius with time have been employed in the simulation stage. The profile of temperature distribution has been utilized to calculate the dimensions of discharge crater. Based on the results of FEM and the experimental observations, a numerical analysis has been developed assessing the contribution of input-parameters on the efficiency of plasma channel in removing the molten material from molten puddles on the surfaces of workpiece and tool at the end of each discharge. The results show that the increase in the pulse current and pulse on-time have converse effects on the plasma flushing efficiency, as it increases by the prior one and decreases by the latter one. Later, the introduced formulas for plasma flushing efficiency based on regression model were utilized to predict the cardinal parameter of recast layer thickness on the electrodes which demands expensive empirical tests to be obtained.

This paper presents the results of experimental studies carried out to conduct a comprehensive investigation on the influence of Electrical Discharge Machining (EDM) input parameters on characteristics of EDM process. The studied process characteristics included machining features, embracing material removal rate, tool wear ratio, and arithmetical mean roughness, as well surface integrity characteristics comprising of the thickness of white layer and the depth of heat affected zone of AISI H13 tool steel as workpiece. The experiments performed under the designed full factorial procedure, and the considered EDM input parameters included pulse on-time and pulse current. The results of this study could be utilized in the selection of optimum process parameters to achieve the desired EDM efficiency, surface roughness, and surface integrity when machining AISI H13 tool steel.

An axisymmetric three-dimensional model for temperature distribution in the electrical discharge machining process has been developed using the finite element method to estimate the surface integrity characteristics of AISI H13 tool steel as workpiece. White layer thickness, depth of heat affected zone, and arithmetical mean roughness consisting of the studied surface integrity features on which the effect of process parameters, including pulse on-time and pulse current were investigated. Additionally, the experiments were carried out under the designed full factorial procedure to validate the numerical results. Both numerical and experimental results show that increasing the pulse on-time leads to a higher white layer thickness, depth of heat affected zone, and the surface roughness. On the other hand, an increase in the pulse current results in a slight decrease of the white layer thickness and depth of heat affected zone, but a coarser surface roughness. Generally, there is a good agreement between the experimental and the numerical results.

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