Papers by Keyword: WEDM

Abstract: Superalloys, referred to as nickel alloys, have several uses in engineering and are widely used in industries that are as diverse as chemical processing and food processing. The high thermal conductivity and high strength of these materials make them hard to remove material from with traditional processing techniques. The majority of modern techniques for machining harder materials are alternatives to older methods. The present study is focusing on Wire Electrical Discharge Machining (WEDM), a modern machining technique used for the processing of tougher materials. The aspiration of this work is to present a Taguchi-based Grey technique that can be used to optimize a number of different performance indicators. The connection between the input and output variables has been analyzed using a regression model. Taguchi's design approach has been applied to the design of trials, with the Pulse on/off time and the applied current serving as independent variables. For enhancing the multiple machining performance of nickel alloy during Wire Electrical Discharge Machining (WEDM), this experimental effort seeks to pinpoint the most effective variables. This is accomplished using the Taguchi-Grey method. The performance analysis offers producers with concrete proof of the efficiency of evolved systems, allowing them to make well-informed and effective choices.

Abstract: Abstract. This study aims to investigate wire electrical discharge machining of copper alloys. Extensive research was done to design an optimum cutting method with adequate wire balance to achieve the requisite surface smoothness and geometrical dimensional correctness. Parameters were used in this work to simulate the process pulse-on time, pulse-off time, peak current, servo feed-rate, servo-volt, wire-feed rate, wire tension, and water pressure. For each given treatment requirement, the primary impacting elements are highlighted. The results are the best standard settings that have been designed to satisfy the client’s varied developing needs. A low pulse achieves superior surface polish on time and a high pulse off time. According to the (ANOVA) findings, the most significant cutting parameter is the pulse on-time (Ton), which affects surface roughness by (42.922)%, followed by pulse off time (Toff), which affects surface roughness by (24.860)%, and servo feed (SF), which affects surface roughness by (6.850)%. The impact of the process variables was wire tension on response characteristics, dimensional deviation, cutting rate, and surface roughness.

Abstract: 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.

Abstract: Wire-cut electrical discharge machining (WEDM) has emerged as the most important non-traditional machining technique in the recent years due to its exceptional accuracy and capability to produce net near shape components of electrically conductive materials. Ti-6Al-4V alloy is a hard-to-machine material and popularly used in bio-medical, aerospace, automotive, defence applications etc. due to its distinct merits. In this work, Taguchi optimization technique is applied to obtain optimum cutting conditions for material removal rate (MRR) and power consumption (PC) in WEDM of Ti6Al4V alloy. The result showed 16.38% improvement in MRR and 10.36% reduction in PC at the optimal parameter settings compared to initial cutting conditions. ANOVA result established pulse off time and current as highly significant process parameters affecting MRR (I: 56.58%, T_off: 23.57%) and PC (T_off: 43.26%, I: 31.24%). The response surface variation PC and MRR is studied using 3D plots. Surface morphology of machined component using scanning electron microscope images is also discussed.

Abstract: This paper presents the experimental work of the surface roughness, surface topography, elementary analysis and microhardness of wire electro-discharge (WEDM) machining of grade 5 titanium alloy (Ti-6Al-4V). Ti-6Al-4V has wide range of application in alloys due to its superior mechanical properties such as corrosion resistance, high tensile strength and toughness. Based on its great hardness value, conventional machining leads to high rates of tool wear, thus, WEDM is an alternative to manufacture Ti-6Al-4V, in which better surface characteristics can be produced. This work explores the surface integrity of Ti-6Al-4V alloy after WEDM in different input parameter. From the experimental work, good surface integrity can be achieved with low peak current. The scanning electron microscope (SEM) analysis depicted the appearance of craters, crack, recast layer and globule of debris on the machined surface. Within the chemical composition on the machined surface, titanium seizes the highest percentage as there is no alternation of the metallurgical structure of the parent material. The microhardness value gradually increases from the machined surface to the parent material of Ti-6Al-4V due to over-aging of the machined surface and the work hardening during the process.

Abstract: One of the non-conventional machining processes widely used in the industry is the wire electrical discharge machining (WEDM). This process has many advantages, like the great precision and quality that can be achieved. As well as other manufacturing operations, the success of the process relies on a correct selection of the cutting parameters. The present paper outlines an experimental study to optimize the machining time and the surface roughness in WEDM of AISI D2 tool steel during roughing machining. The Taguchi methodology is used to evaluate the effects and contributions of the pulse-on time, pulse-off time, servo voltage, and wire speed, on the response variables. The desirability method is employed to define a set of cutting parameters that allows reducing both machining time and surface roughness at the same time. The pulse-on time is the most significant factor for reducing the machining time, followed by the servo voltage, the pulse-off time and the wire speed. For surface roughness, the pulse-off time is the factor with the greatest influence over the response variable. The results obtained show that the machining time is reduced by 4.65%, and the surface roughness is diminished by 4.60% when compared with the initial values that are commonly used in the machining of AISI D2 tool steel. Therefore, greater production rates can be achieved without compromising the quality of the machined parts.

Abstract: Wire electric discharge machine (WEDM) is a non-conventional machining process used to machine the hard to cut materials. WEDM has wide applications in die and punch industries, automobile, aerospace and medical industries. In this process the material is processed with the help of a wire electrode. In present work, Al6063/SiC/Ti composite was processed with the help of WEDM. As this spark-erosion machine tool have number of input process parameters, so to process any material it became mandatory to investigate the range of the machining parameters in which machine tool operate successfully. Every material represents its unique material characteristics due to which it can be machined successfully in a limited range of the parameters. Above and below this range the wire will break abruptly. So, in this present work an attempt has been made to investigate the range of the process parameters in which WEDM can process Al6063/SiC/Ti composite efficiently. The input parameters considered for the present work are pulse on-time, pulse off-time, servo voltage, peak current, wire feed and wire tension. After the experiments it was found that the pulse on-time, pulse off-time, servo voltage and wire-feed were the significant process parameters in the investigations of cutting rate and surface roughness.

Abstract: Wire Cut Electrical Discharge Machining (WEDM) is a non-conventional thermal machining process which is capable of accurately machine alloys having high hardness or part having complex shapes that are very difficult to be machined by the conventional machining processes. The WEDM finds applications in automobiles, aero–space, medical instruments, tool and die industries, etc. The input parameters considered for WEDM are pulse on time, pulse off time, flushing pressure, servo voltage, wire feed rate and wire tension. Performance of WEDM is mainly assessed by output variables such as, material removal rate (MRR), kerf width (Kw) and surface roughness (Ra) of the work piece being machined. Looking at the need of a suitable optimization model, the present work explores the feasibility of machine learning concepts to predict optimum surface roughness and kerf width simultaneously by making use of experimental data available in the literature for machining of Hastelloy C– 276 using WEDM. In most of the literatures, single objective optimization has been carried out for predicting optimum cutting parameters for WEDM. Hence, the present work presents a methodology that makes use of a machine learning algorithm namely, gradient descent method as an optimization technique to optimize both surface roughness and kerf width simultaneously (multi objective optimization) and compare the results with the existing literatures. It was observed that the input parameters such as pulse on time, pulse off time, and peak current have significant effect on both surface roughness and kerf width. The gradient descent method was successfully used for predicting the optimum values of response variables.

Abstract: Difficult-to-cut materials, generally high hardness, strength and toughness, are generally difficult to machine in conventional machining. Also tool wear is high in conventional machining processes. Wire Cut Electric Discharge (WEDM) machining is particularly used for machining complex profiles, demanding very high accuracy. The current work focuses on the optimization of roughness of a surface that is machined using WEDM; the process parameters considered for optimization are pulse-on-time (P_on), pulse-off time (P_off), wire feedrate (WFR) and spark gap voltage (SGV). One of the surface integrity aspect is considered as surface roughness (SR) and other related to machining output considered as material removal rate (MRR) for the output responses. The paper presents, a multi-criteria decision making technique, with Grey Relational Analysis (GRA) integrated with Particle Swarm Optimization (PSO) for optimizing the process parameters. Further, confirmation tests that were conducted also validated the improvement in SR and MRR.

Abstract: Machinability of aerospace material, Inconel 625 through Wire cut electrical discharge machining has been performed and compared using Taguchi’s Orthogonal L18 (2¹*3⁵). Normal diffused and cryogenic treated diffused wires are being used as a tool electrode to investigate the effects of machining parameters viz. tool electrode, peak current, pulse on time, pulse off time, wire feed and wire tension on the response MRR. The present study resulted that cryogenic treated tool electrode give better performance in comparison to normal wire electrode assisting in improving stock removal and less electrode wear. Pulse on time and peak current are observed as the most influenced parameter. Scanning Electron Microscopy (SEM) studies has been conducted and presented.