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Problem statement: Electrical Discharge Machining (EDM) is now a well-established machining option in many industries. Tungsten carbide (WC-Co) is an important tool and die material mainly because of its high hardness, strength, wear resistance and high melting point. Normally, EDM is capable of machining geometrically complex or hard material component, that are precise and difficult to machine. The objective of this research is to study the performance of different electrode materials on tungsten carbide workpiece with EDM process. Approach: The electrode materials were graphite (Poco EDM-3), copper-graphite (Poco EDM-C3) and copper-tungsten (solid).The important parameters were discharge current, on time, off time, open-circuit voltage and electrode polarity. A workpiece material was a tungsten carbide (W 90-Co10). Results: The results show that the electrode negative polarity performs very well, Poco EDM-3 gives higher Material Removal Rate (MRR). Both powder electrode (EDM-3 and EDM-C3) give the better MRR and EWR more than solid electrode. Conclusion: The suitable duty factor is 11%. The Surface Roughness (SR) of copper-tungsten give the best when current peak intensity not over 20 amperes.

The performance of electrical discharge machining for drilling holes decreases with machining depth because the conventional flushing and electrode cannot completely eliminate debris particles from the machining area. In this study, a modified electrode for self-flushing in the electrical discharge machining process with a step cylindrical shape was designed to improve machining performance for deep hole drilling. The experimental results of the step cylindrical electrode showed that the material removal rate increased by approximately 215.7%, 203.8%, and 130.4%, and the electrode wear ratio decreased by approximately 47.2%, 63.1%, and 37.3%, when compared with a conventional electrode for the diameters of 6, 9, and 12 mm, respectively. In addition, the gap clearance and concavity of the side wall of the drilled hole was reduced with the step cylindrical electrode. The limited high flank of the electrode led to an increase in the escape area of the debris that was partially removed from the machining area, and the limited secondary spark on the side wall of the electrode resulted in a reduction in machining time.

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In the industrial field, electric discharge machining (EDM) is the most commonly used non-traditional machining process because it has the potential to machine electrically conductive materials of high hardness. To satisfy the need for rapid and economical fabrication of EDM electrodes, techniques that use the addition of more metal in the manufacturing process are gaining in popularity. This study presents an investigation of the characterization of ternary metals (Cu–Ni–TiN) for EDM electrodes by using powder metallurgy, which leads to enhancement of the mechanical properties, such as the hardness, electrical properties, and other properties, for the formation of Cu in Ni-TiN electrodes using a cold press at pressures of 18, 20, and 22 MPa. The influences of the parameters of this process were identified for the betterment of Cu–Ni–TiN on the surface. The specimens were calcined in a furnace at 1100 °C for 1 h, with a mixture of argon and hydrogen gas as a controlled gas in the ratio of 95:5. The specimens were investigated in terms of hardness, electric resistivity, apparent density, and porosity. The results show that the 80% Cu–3% Ni–17% TiN electrode at 18 MPa had the highest hardness (124.38 HV) and the lowest electric resistivity (0.39188 cm), while the specimen increased Cu with a ratio of 85% Cu–3% Ni–12% TiN, and a pressure of 20 MPa was found to have the highest density (8.5472 g/cm3) and the lowest porosity (6.2922%). As a further confirmation of the above results, the X-ray diffraction (XRD) patterns of the surfaces of the specimens exhibited major phases that supported the ternary Cu–Ni–TiN phase. However, we also achieved the successful use of Cu–Ni–TiN electrodes as a titanium source (as an alternative to the conventional metal powder) to provide a novel approach to fabricating composite electrodes through the EDM process.

In this study, effect of machining parameters and wear mechanism in milling process of mold steel AISI-P20 and AISI-1050, using 10 mm twin flute type end mill diameter. The experimental results found that characteristics of milling surfaces and wear of the mill end were directly influenced by changes of parameters for all test conditions. As a result, the quality of milling surfaces also changed. However, mould steels which had the good quality surface is AISI-1050, with roughnesses of 2.120 μm. Quality milling surfaces were milled by using the most suitable parameter feed rate of 45 mm/min, a spindle speed of 637 rpm and a cut depth level of 3 mm, for both grades. Moreover, material removal rate and duration of the milling process, the milling end mills affect wear of the edge in every bite when the feed rate is low, high speed and level depth of cut at least. It was found that limited wear less will affect the surface roughness (Ra) represents the good quality surface.

Abstract. Wire electrical discharge machining (WEDM) is a widespread technique used in manufacturing industry for high precision machining of all types of conductive materials such as metals and its alloys of any hardness which are difficult to machine with traditional techniques. In order to get a precise workpiece with good surface quality, some extra repetitive finish cuts along the rough cutting contour are necessary. The selected parameters are servo voltage (SV) and voltage (V). The goal of the research was to obtain accurate dimension (10 + 0.005 mm and surface roughness < 0.46 microns). The experiment material is SKD-11 steel. The experiments are designed by 3k full factorial experimental design at 3 level 2 factors and 9 experiments with 2 replicates. The experiment determines the significant effective factor at confidential interval 95%. The SV factor is the significant effective factor and voltages parameter affects to the average roughness surface. Experimental results show that a surface roughness under 0.46 micron and accurate dimension value + 5 micron of 10 x 10 millimeters can be obtained.