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In the present research, the AZ31 alloy is machined by wire-cut electric discharge machining (WEDM). The experiments were designed according to the Box-Behnken design (BBD) of response surface methodology (RSM). The input process variables, namely servo feed (SF), pulse on-time (Ton), servo voltage (SV), and pulse off-time (Toff), were planned by BBD, and experiments were performed to investigate the cutting rate (CR) and recast layer thickness (RCL). The analysis of variance (ANOVA) was performed to determine the influence of machining variables on response characteristics. The empirical models developed for CR and RCL were solved using Multi-Objective Particle Swarm Optimization (MOPSO). Pareto optimal front is used for the collective optimization of CR and RCL. The optimal solution suggested by the hybrid approach of RSM-MOPSO is further verified using a confirmation test on the random setting indicated by the hybrid algorithm. It is found that the minimum RCL (6.34 µm) is obtained at SF: 1700; SV: 51 V; Toff: 10.5 µs; and Ton: 0.5 µs. However, maximum CR (3.18 m/min) is predicted at SF: 1900; SV: 40 V; Toff: 7 µs; and Ton: 0.9 µs. The error percentage of ±5.3% between the experimental results and predicted solutions confirms the suitability of the proposed hybrid approach for WEDM of AZ31.

Abstract Optimization of the manufacturing conditions with more than one performance characteristics have been a thing of concern, especially for Response Surface Method (RSM) optimization. Hence, this study addressed this challenge by reanalyzing a data presented in a previous study using grey relational analysis (GRA) and regression analysis. Central Composite Design (CCD) of RSM with high and low values of manufacturing conditions; voltage (50, 70) V, current (8, 16) A, pulse ON time (6, 10) μs, and pulse OFF time (7, 11) μs. The manufacturing conditions for optimal biomedical Ti-13Zr-13Nb alloy were obtained to be 50V voltage, 8A current, 6 μs pulse ON time, and 11 μs pulse OFF time. It was also revealed that the mathematical model was very efficient because the modeled GRG was in consonant with the experimental one. In addition, it was also established that current was the most significant manufacturing condition with a contribution of 47.27%. Voltage, factors interactions and residual error were insignificant on the GRG value of the titanium alloy. In conclusion, it can be deduced that the a small value of voltage within the considered settings could be used to manufacture better grade Ti-13Zr-13Nb alloy and also the small value of residual error showed the high manufacturability of the material.

With the enhancement in science and technology, necessity of complex shapes in manufacturing industries becomes essential for more versatile applications. These lead to demand for light weight and durable materials for applications in aerospace, defence, automotive, as well as sports and thermal management. Due to its high-tech structural, functional applications like defence, automobile, aerospace, thermal sensitive materials. Al-Matrix composites are considered as one of those classes of advanced engineering materials. In the present study, Al-RHA (Rice Husk Ash) composites are prepared by powder metallurgy route using 10% and 15% RHA by weight as reinforcement. Presence of abrasive particles leads to difficulty of conventional machining on Al-RHA composites hence non-conventional machining WEDM (Wire-Electric Discharge Machining) has been investigated. Suitable machining parameters for composites using wire EDM have been tried to get maximum material removal rate and speed. Optimizations of experimental parameters have been studied using Taguchi and Anova to standardize the process parameters for machining. Prime process parameters like servo-voltage, pulse-on time and pulse-off-time have been taken into consideration to study cutting quality of Al-RHA Metal matrix Composite using cutting speed as response parameters while effect of RHA weight fraction addition is also considered for evaluation to understand its influence on affecting the response.

Electrical Discharge Machining (EDM) process is a widely used machining process in several fabrication, construction and repair work applications. Considering Pulse-On Time, Pulse OFF time, Peak-Current and Gap voltage as the inputs and among all possible outputs, in the present work Material Removal Rate and Surface Roughness are considered as outputs. In order to reduce the number of experiments Design of Experiments (DOE) was undertaken using Orthogonal Array and later on the outputs were optimized using ANN and PSO. It was found that the results obtained from both the techniques were tallying with each other.

Abstract: The manufacturing industry is changing very drastically in all the aspect regarding the manufacturing technology as well as the quality concern as per as the quality is considered. Quality is becoming a significant trend in todays growing automobile industry. In the field of metal cutting operations, the surface roughness is becoming more dominant parameter as per as the quality of the component is considered. Electrical discharge machining is becoming a most powerful non conventional machining which is being widely used in the field of machining. Most specifically our work was conducted on the electrical discharge wire cut machining for achieving the desired surface roughness (Ra) and adequate material removal rate (MRR). The input parameter for our research work were selected as Peak current, pulse on time & pulse off time while the output parameter was selected as MRR and the surface roughness. Aluminum 6082 Grade material is used as a specimen and the research methodology implemented for the research work is taguchi and Anova. Keywords: Wire cut EDM, Taguchi, MRR surface roughness, Anova.

Abstract: Wire electrical discharge machining is extensively used in machining of conductive materials. The WEDM process has the ability to machine complex shapes and hard electrically conductive metal components precisely. The main goal of wire electrical discharge machine manufacturers and users are to achieve a better stability and high productivity of the process with desired accuracy and minimum surface damage.The main objectives of the present research are to experimentally study the effect of various process parameters like pulse on time, pulse off time, wire feed, and wire tension on the performance measures like material removal rate, surface roughness and wire wear ratio. WEDM is a widely recognized unconventional material cutting process used to manufacture components with complex shapes and profiles of hard materials. In this paper we are presenting the development of WEDEM process using various pre define parameters using Taguchi method. Index Terms: WEDM, doe, orthogonal array, parameters, Taguchi method, H13, HDS, mean of means, SF, MRR, Ra, etc.

Abstract In this research work, an attempt was made to machine Ti6Al4V titanium alloy utilizing AA6061/10Gr composite tool. The composite tool was fabricated using stir casting technique and Al2O3 particles of size 5µm were incorporated in the dielectric fluid to enhance the machining performance. Experiments were conducted by varying Al203 concentration, pulse on time, current, and pulse off time, and the responses Material Removal Rate (MRR), Tool Wear Rate (TWR), and Surface Roughness (Ra) were recorded. Experiments runs were planned using Taguchi orthogonal array. The results revealed that adding powder increases MRR and TWR owing to the excessive heat generation and bridging effect respectively. The best surface finish was attained due to the increase in spark gap and complete flushing of machined debris. Coating of materials over the machined specimen was observed when the parametric value of Ton was higher than 60s under PMEDM conditions. Pits, craters and cracks were observed on the machined topography which was eliminated when 5g/l of Al2O3 particles were added to dielectric fluid. MEIOT technique was utilized for optimization and it was observed that Ton 15µs, Toff 4µs and current 7A and powder concentration of 10g/l results in best machining performance.

In the current study, an optimization process of powder-mixed electrical discharge machining (PMEDM) process when machining cylindrically shaped parts made of hardened 90CrSi steel is reported. In this study, SiC powder was mixed into the Diel MS 7000 dielectric solution. Additionally, graphite was chosen as the electrode material. The multi-objective functions were minimizing the surface roughness (SR) and electrode wear rate (EWR) and maximizing the material removal rate (MRR). The used input parameters of the optimization process included the powder concentration, the pulse-on time, the pulse-off time, the pulse current, and the servo voltage. A combination between the Taguchi method and the grey relation analysis (GRA) method with the support of Minitab R19 software was used to design the experiment and analyze the results. It was found that the optimal set of process parameters that can satisfy the above responses are Cp of 0.5 g/L, Ton of 8 µs, Toff of 8 µs, IP of 5 A, and SV of 4 V.

The present study looks into the effect of WEDM process parameters on the material removal rate (MRR) and surface roughness (SR) responses when machining hybrid composites (Al-Si12/boron carbide/fly ash) using the Taguchi technique. Fly ash and boron carbide (B4C) particles were used for reinforcement (3%, 6%, and 9% by weight), and aluminium alloy (Al-Si12) was used as a matrix material. ANOVA was used to find out the importance of machining factors that affect the quality features of the WEDM process, as well as the relative role of input parameters in determining the WEDM process’ responses. The greatest impact on the response is finalised by the signal-to-noise (S/N) ratio response analysis. However, as a last step, a confirmation experiment with the best combination was carried out to predict and validate the accuracy of the observed values. As the pulse on time and reinforcement increases, MRR also increases. As the gap voltage, wire feed, and pulse off time decrease, it increases. SR is increased by increasing the gap voltage, pulse on time, and pulse off time, wire feed, and reinforcement. The maximum MRR of 38.01 mm3/min and the minimum SR of 3.24 μm were obtained using optimal machining conditions.

Abstract The basic building block of any electric discharge machine is a generator, which ensures the operation of material separation itself. Not only the erosion rate and electricity consumption but also the quality of the machined surfaces depend on the design of the generator. These key factors for efficient machining have been investigated using a new energy-saving and powerful generator developed for the electric discharge machine (EDM) while machining 1.2363 and 1.2343ESR steels. In order to monitor and model the responses in the form of eroding rate and surface quality, a two-level half-factor experiment was performed with one replication at the corner points and two replications at the central points, for a total of 80 rounds. Both graphite and copper electrodes of sizes 10x10 mm and 100x100 mm were used for eroding and the influence of parameter settings: Open-voltage, Pulse current, Pulse on-time and Pulse off-time was monitored. It was found out that the shape of the electrode and Pulse current have the most significant effect on the erosion rate. The parameters Pulse current, Pulse on-time and their mutual interaction have the most significant effect on the surface topography. Statistically significant factors influencing the occurrence of defects turned out to be Pulse current, Pulse on-time and Material of workpiece, where it can be seen that the material 1.2343ESR is significantly less prone to the formation of surface defects.