Experimental Investigation of the Micro-hardness of EN-31 Die Steel in a Powder-Mixed Near-Dry Electric Discharge Machining Method

Abstract

The Powder-Mixed Near-Dry Electric Discharge Machining (PMND-EDM) methodology has proven to be efficient in terms of machining rate, surface morphology, and environmental friendliness, unlike traditional EDM. In this study, the presence of a conductive metallic powder (zinc) in the dielectric medium was responsible for changing the topography of the workpiece (EN-31) and resulted in a higher micro-hardness value of the machined component. In this research, an approach has been made to optimize the significant process parameters by using a Taguchi L9 orthogonal array (OA) to obtain machined components with higher values of micro-hardness, which was measured in terms of Vickers hardness HV. The selected process parameters were tool diameter, mist flow rate, metallic powder concentration, and dielectric mist pressure. By introducing foreign particles (metallic powder), the topography of the machined products has been improved, and the micro-hardness value was found to be enhanced. The confirmation experiment was performed for optimal process parameter settings, and the enhanced microhardness value was found to be 506.63 HV in the machined EN-31 die steel.

Analysis and Optimization of Process Parameters of Powder Mixed Near Dry- EDM by using Grey Relational Optimization

“…You can find 1. Chemical composition or structure and physical characteristics of the workpiece -EN-31 material [22][23][24] the properties of the workpiece and tool in Table 1 and Table 2, respectively.…”

“…The setup's panel incorporates various key components, including a dielectric chamber for mixing, mist flow meter for a dielectric, manual regulators, and pressure gauges that play a crucial role in determining the working pressure of the dielectric medium. After that, the material removal rate is calculated according to Sundriyal s. discussed in literature survey 22,28 .…”

Sustainable developments in near-dry electrical discharge machining process using sunflower oil-mist dielectric fluid

“…In the early stages of the traditional EDM technique, vegetable oil served as the dielectric uid. Due to its good sustainability, availability, and affordability, used vegetable oil would be employed as a dielectric uid in electrical applications (Sundriyal et al 2020a). The formation of harmful pollutants such as sulfur, ozone-forming potential, sulfur oxides and sulfates, carbon dioxide, and carbon monoxide during the burning of biofuels was prevented or only partially prevented (Singh and Sharma 2017).…”

Experimental investigation and performance enhancements characteristics of gaseous assisted powder mixed near dry electric discharge machining

“…2,3 It was also illustrated that near-dry EDM with powder additives was efficient in performance characteristics such as higher material removal rate, reduced residual stress and better surface quality in the machined products. [4][5][6][7][8][9] Investigations related to field of powder mixed EDM has also been performed by researchers. Silicon carbide (SiC) powder additives were suspended in the dielectric oil for powder mixed EDM (PMEDM) to study surface topography of Ti-6Al-4V-ELI work material.…”