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High-intensity electrical discharges are used in the unconventional technique known as electrical discharge machining (EDM) to machine metals of any hardness. Due to their extraordinary conductivity and strength, carbon nanotubes (CNTs) have recently been explored in EDM too. However, material removal with CNT yarn (CNTY) has not been studied thoroughly. This work advocates the use of a pristine CNTY as an EDM tool. The feasibility is examined through characterization and material removal experiments. The measurements show that the CNTY (< 100 µm in diameter) has an electrical conductivity and current carrying capacity of 2.66 × 104 S/m and 1.76 × 103 A/cm2, respectively. Steel and aluminum are the workpieces for machining experiments conducted in air and hydrocarbon oil dielectrics, respectively. Significant material removal and extended tool life are obtained in the air dielectric. It is suggested that the oxidation of steel increases material removal in the air while reducing tool life. The effect of tool thickness is also investigated. Thicker (> 100 µm) multi-ply tools extend tool life and, therefore, machining time by more than 14 s in the air and nearly 2.5 s in the oil. Other factors that restrict machining include intensified discharges and the shielding effect of the carbide layer formed on the workpiece. [ABSTRACT FROM AUTHOR]

Inconel 625 superalloy and stainless steel 304 are known for their significant corrosion resistance along with their high hardness and strength. Therefore, they are used in a wide range of industries, including oil and gas and nuclear. Electrical discharge machining is among the most widely used processes for machining of these metals. However, this process has limitations, such as low material removal efficiency, high surface roughness, and the formation of a recast layer. Therefore, in this study, the effective parameters on increasing the material removal efficiency and reducing recast layer thickness are investigated. These parameters include the dielectric fluid, electrode material, discharge current, and pulse duration. After performing the test matrix, the effect of each of the input parameters on the material removal rate, surface roughness, and thickness of the recast layer is evaluated using the ANOVA method. The results of this analysis showed that the type of dielectric fluid and the presence of silver oxide nanoparticles have a significant effect on output variables. When using sunflower oil fluid containing nanoparticles and the silver electrode, the recast layer and surface roughness are reduced, while the average material removal rate increases by 40% compared to the traditional mode. Also, due to the biodegradability of deionized water and sunflower oil fluids, the environmental sustainability of the process in this study is increased and while increasing productivity, it leads to the sustainable development of the EDM process. [ABSTRACT FROM AUTHOR]

This study investigates how machining characteristics and surface modifications affect low-carbon steel (S15C) during electrical discharge machining (EDM) processes with semi-sintered electrodes. Among the machining characteristics determined, the material removal rate (MRR), surface deposit rate (SDR), and electrode wear rate (EWR) are included. Additionally, exactly how semi-sintered electrodes affect the surface modifications is also evaluated by electron probe microanalyzer (EPMA), micro hardness, and corrosion resistance tests. The experimental results confirmed that the composition of the semi-sintered electrodes is transferred onto the machined surface efficiently and effectively during the EDM process, and that the process is feasible and can easily form a modified layer on the machined surface. [ABSTRACT FROM AUTHOR]