Principles and Characteristics of Different EDM Processes in Machining Tool and Die Steels

Abstract

Electric discharge machining (EDM) is one of the most efficient manufacturing technologies used in highly accurate processing of all electrically conductive materials irrespective of their mechanical properties. It is a non-contact thermal energy process applied to a wide range of applications, such as in the aerospace, automotive, tools, molds and dies, and surgical implements, especially for the hard-to-cut materials with simple or complex shapes and geometries. Applications to molds, tools, and dies are among the large-scale initial applications of this process. Machining these items is especially difficult as they are made of hard-to-machine materials, they have very complex shapes of high accuracy, and their surface characteristics are sensitive to machining conditions. The review of this kind with an emphasis on tool and die materials is extremely useful to relevant professions, practitioners, and researchers. This review provides an overview of the studies related to EDM with regard to selection of the process, material, and operating parameters, the effect on responses, various process variants, and new techniques adopted to enhance process performance. This paper reviews research studies on the EDM of different grades of tool steel materials. This article (i) pans out the reported literature in a modular manner with a focus on experimental and theoretical studies aimed at improving process performance, including material removal rate, surface quality, and tool wear rate, among others, (ii) examines evaluation models and techniques used to determine process conditions, and (iii) discusses the developments in EDM and outlines the trends for future research. The conclusion section of the article carves out precise highlights and gaps from each section, thus making the article easy to navigate and extremely useful to the related research community.

Surface Damaging of Brass and Steel Pins when Sliding over Nitrided Samples Cut by Finishing and Roughing EDM Conditions

“…Nitrided finishing EDM specimens reached similar hardness values to [ 18 ]. Regarding the EDM surface morphology ( Figure 3 a,c), the results present the same features as the work reported in [ 13 ], where the sample was EDMed with short pulses and a long duration.…”

“…Here, parameters such as type of tool and its geometry [5][6][7][8], the machining strategy [9,10] and the operational conditions [11,12] play an essential role on its final surface properties, and these parameters are tightly related to the service efficiency of the die (for example, fatigue resistance). Another option is the Electrical Discharge Machining (EDM) of the dies [13]. EDM is capable of making complex shapes and deep cavities; the only requirement is to work with an electrically conductive material.…”

Multi-response optimization for Nimonic alloy miniature gear fabrication using wire electrical discharge machining

“…Step 4: Calculate separation measures by using equations (5) and (6). The ideal solution for the separation of alternative is given as:…”

“…[2][3][4][5] The wire-EDM (WEDM) employs spark energy produced from electric discharge for material removal and is regarded as the process of choice. 6 The gears with diameter of less than 10 mm are classified as miniature gears. In comparison, the gears with a diameter between 1 and 10 mm and less than 1 mm are meso and micro gears, respectively.…”

Recent Advances and Perceptive Insights into Powder-Mixed Dielectric Fluid of EDM

“…The electrical discharges are the results of controlled pulses of direct current and occur between the tool electrode (cathode) and the work piece (anode) [ 12 ]. Generally, one of the largest uses of the EDM process is in tool-, die-, and mold-making [ 13 ]. In the powder-mixed EDM (PMEDM) process, electrically conductive powder is used in dielectric medium which reduces the insulating strength of dielectric fluid, and it increases the spark gap between tool and work piece which will result in an improvement of material removal rate (MRR) and surface finish [ 14 , 15 ].…”