Multi-objective optimization of wire electrical discharge machining process using evolutionary computation method: Effect of cutting variation

Abstract

This article focuses on comparing the performance of brass wire and zinc-coated brass wire that are widely used as the wire electrode in wire electrical discharge machining. To this end, an evolutionary computation method is presented based on non-dominated sorting genetic algorithm in order to find an optimization of rough cutting of the Ti-6Al-4V titanium alloy with the aid of response surface methodology modeling. This research examines the effects of three process parameters, namely, pulse on-time, pulse off-time, and peak current on the process outputs, that is, material removal rate, sparking gap, and white layer thickness. The obtained results indicated that zinc-coated wire was more predictable and it showed more reliable response in the experimental and modeling results. Additionally, the optimization results for both wires demonstrated the high performance of non-dominated sorting genetic algorithm approach to obtain the Pareto optimal set of solutions.

Experimental investigation of surface integrity after wire electro-discharge machining of Ti–6Al–4V

“…Also, in low T off time, heat dispersion decreases, causing more heat entrapment and melted material in the surface, which produces thicker white layer. These results are in agreement with other research works as mentioned in the literature review [13,15,16]. Moreover, Ghodsiyeh et al [27] reported that IP and SV have more significant effects on the WLT than the pulse-on time and pulse-off time in WEDM machining of Ti-6Al-4V.…”

“…A comprehensive literature review has been performed on various aspects of WEDM process and is summarized in table 1. Although several attempts were made to understand the mechanism of formation and properties of the white layer and HAZ, it is evident from the literature review that few research works [10][11][12][13][14][15][16] have been conducted to model the process by correlating the dominant input parameters with the white layer and HAZ depth as the machining performance, especially since it is not easy to identify and measure HAZ.…”

Prediction of the heat-affected zone of tool steel EN X37CrMoV5-1 after die-sinking electrical discharge machining

“…Building on the studies of several authors was the assumption that the development of microhardness does not need to be the same across the eroded surface, and it was therefore chosen the procedure for implementing measurements in different parts of the eroded surface. 28 Due to the expected very small total depth of the HAZ, which is the order of tens of µm, was created the certain problem in the methodology of measuring microhardness. Because the eroded surface has very small dimensions of 10 × 10 mm 2 , it was not possible to use the bevelled cross-sectional method.…”

“…26 It was heat-treated by hardening in air at temperature about 1030°C with subsequent tempering at the temperature about 580°C to the hardness of 53 HRC ( Figure 3). Samples were prepared by pickling in chemical solution Armohib 28 (Akzo Nobel Surface Chemistry AB, Sweden) on the base of H 3 PO 4 with concentration of 15% at constant temperature 40°C with a total duration of action for 10 min. The advantage of using the stain on the base of H 3 PO 4 is the creation of a thin phosphate film which in consequence protects the surface against its re-oxidation with atmospheric oxygen O 2 and H 2 O humidity.…”

Modelling and multi-response optimization of wire electric discharge machining parameters using response surface methodology and grey–fuzzy algorithm

“…Response surface methodology (RSM) also helps to find interaction effect among the control parameters on responses. 17 Golshan et al 18 presented a mathematical model using RSM method to optimize the process parameters and analyse the model to signify the process behaviour of WEDM operation.…”