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WEDM (Wire electrical discharge machining) is a precision machining method for cutting electrically conductive materials. It is an unconventional machining process that produces precision parts that match the dimensional tolerances of our designs within the range of ±0.0001mm. As the residual stress results in premature failure of parts, the WEDM is preferred for hard to machine materials such as Inconel, Nickel, and other Super alloys. In the present paper, earlier and recent work was reviewed, segregated and evaluated on the effect of wire material, diameter, dielectric fluid, wire wear, pulse on and off times and machining characteristics such as kerf size, machining efficiency, material surface characteristics, etc. This paper also focused on hybrid and ultrasonic-assisted WEDM used for machining of different materials. This paper discussed the major research studies in WEDM.

WEDM (Wire electrical discharge machining) is a precision machining method for cutting electrically conductive materials. It is an unconventional machining process that produces precision parts that match the dimensional tolerances of our designs within the range of ±0.0001mm. As the residual stress results in premature failure of parts, the WEDM is preferred for hard to machine materials such as Inconel, Nickel, and other Super alloys. In the present paper, earlier and recent work was reviewed, segregated and evaluated on the effect of wire material, diameter, dielectric fluid, wire wear, pulse on and off times and machining characteristics such as kerf size, machining efficiency, material surface characteristics, etc. This paper also focused on hybrid and ultrasonic-assisted WEDM used for machining of different materials. This paper discussed the major research studies in WEDM. [ABSTRACT FROM AUTHOR]

Micro dry wire electrical discharge machining (μDWEDM) is a process where gas is used as the dielectric fluid instead of a liquid. In this process, certain modifications of wire electrical discharge machining (WEDM) are needed during the machining operation to achieve stable machining. Smooth and stable machining operation in μDWEDM process remains as a critical issue. Thus, this paper presents the investigation of process parameters for a stable μDWEDM process. The investigation was performed on a stainless steel (SS304) with a tungsten wire as the electrode using integrated multi-process machine tool, DT 110 (Mikrotools Inc., Singapore). The experimentation method used in this phase was a conventional experimental method, one-factor-at-a-time (OFAT). Types of dielectric fluid, dielectric fluid pressure, polarity, threshold, wire tension, wire feed rate, wire speed, gap voltage, and capacitance were the controlled parameters. The machined microchannels were observed using scanning electron microscope (SEM). Stable and smooth machining operation of μDWEDM was found to be with compressed air as the dielectric fluid, workpiece positive polarity, 24% threshold, 0.0809 N wire tension, 0.2 μm/s wire feed rate, and 0.6 rpm wire speed. [ABSTRACT FROM AUTHOR]

Dry wire electric discharge machining (WEDM) process has been proposed to cut intricate and complex profiles on difficult to cut thin materials with a view to improve material integrity and minimize environmental impact and operators health issues. However, longer cutting cycles and poor geometrical accuracy are the inherent drawbacks of the dry WEDM process. In this paper, the authors have proposed a novel method using concentric flow of gaseous dielectric fluid for the dry WEDM process. The proposed method is intended to provide efficient flushing of debris from the sparking gap and minimizes the debris resolidification on the material surface. Which in turns, minimize the cutting cycles and improve geometrical accuracy of the work material. Titanium alloy, Ti-6Al-4 V (ASTM Grade 5) thin sheet was used for the experiments using side flow and concentric flow modes with a compressed air jet as dielectric media. Current, air pressure, pulse-on time and pulse-off time have been selected as process parameter, and the effects on cutting velocity (CV), kerf width (Kw) and material removal rate (MRR) were investigated. Results indicate that the proposed concentric flow system resulted in a higher CV and MRR and generated a lower Kw than side flow system of dielectric supply. Results of analysis of variance (ANOVA) indicated that current is the most significant parameter contributing to CV and MRR. However, air pressure and pulse-on time significant parameters for Kw for both the dielectric supply modes. Moreover, the response prediction models developed using regression analysis indicated good conformance with the actual results. Improved performance in the case of CDWEDM indicates that the concentric flow system of dielectric supply can be technically viable and economically feasible alternate to conventional side flow system in order to exploit the dry WEDM process effectively and efficiently. [ABSTRACT FROM AUTHOR]

In the dry wire electrical discharge machining (WEDM) process, the liquid dielectric is replaced with gaseous medium to enhance the machining environment safety. Also, this modification improves the surface quality of machined specimen but decreases the material removal rate of the process. In the present work, experimental study of dry WEDM process has been performed while machining of Al/SiC metal matrix composite. At first, a series of exploratory experiments has been conducted to identify appropriate gas and wire material based on their cutting velocity. After selection of the best gas and best wire, they were used for later stage of experiments. At the next stage, experiment were designed and conducted based on L Taguchi's orthogonal array to study the effect of pulse on time, pulse off time, gap voltage, discharge current, wire tension and wire feed on cutting velocity (CV) and surface roughness (SR). Analysis of variances (ANOVA) has been performed to identify significant factors. In order to correlate relationship between process inputs and responses, adaptive neuro-fuzzy inference system has been utilized. At the end, a grey relational analysis has been used to maximize CV and minimize SR simultaneously. Results indicated that oxygen gas and brass wire guarantee superior cutting velocity. Also according to ANOVA, pulse on time and current were found to have significant effect on CV and SR. [ABSTRACT FROM AUTHOR]