Journal Article

Experimental investigation and multi-objective optimization of eco-friendly near-dry electrical discharge machining of shape memory alloy using Cu/SiC/Gr composite electrode

Krishnaveni, Kondreddi, Medikondu, Nageswara Rao, Dwivedi, Jaiprakash Narain, Boopathi, Sampath, Palaniappan, Murugesan, Gowri, Nagarajan Vasantha

2023

Overview

The near-dry electrical discharge machining processes have been conducted using air-mist or gas mist as a dielectric fluid to minimize the environmental impacts. In this article, near-dry electrical discharge machining (NDEDM) experiments have been performed to improve machining performance using an oxygen-mist dielectric fluid, a copper composite electrode, and Cu-Al-Be polycrystalline shape memory alloy (SMA) work materials. The copper composite electrode is made up of 12 wt% silicon carbide and 9 wt% graphite particles. The oxygen-mist pressure (Op), pulse on time (Ton), spark current (Ip), gap voltage (Gv), and flow rate of mixed water (Fr) were used as process parameters, and the material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) were used as performance characteristics. The global optimal alternative solution has been predicted by the PROMETHEE-II (Preference Ranking Organization METhod for Enrichment Evaluations-II) optimization technique. The best combinations of process parameters have been used to examine the microstructure of composite tools and SMA-machined surfaces by scanning electron microscopy (SEM) analysis. The best global optimum settings (oP: 9 bar, Ip: 60 µs, Ip: 12 A, Gv: 40 V, and Fr: 12 ml/min) are predicted to attain optimum machining performance (MRR: 39.049 g/min, TWR: 1.586 g/min, and SR: 1.78 µm). The tool wear rate of the NDEDM process has been significantly reduced by the copper composite electrode due to increasing microhardness, wear resistance, and melting point. When compared to the pure copper electrode tool, the MRR of NDEDM is improved to 21.91%, while the TWR and SR are reduced to 46.66% and 35.02%, respectively.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V
• Subject: alloys / Aquatic Pollution / Atmospheric Protection/Air Quality Control/Air Pollution / Composite materials / Copper / Earth and Environmental Science / Ecotoxicology / Electric discharge machining / electric discharges / electric potential difference / Electrodes / electron microscopy / Environment / Environmental Chemistry / Environmental Health / Environmental impact / Flow rates / graphene / Material removal rate (machining) / Melting point / Melting points / Microhardness / microstructure / Mist / mists / Multiple objective analysis / Optimization / Optimization techniques / Oxygen / Process parameters / Research Article / Scanning electron microscopy / Shape memory alloys / Silicon carbide / Surface roughness / Tool wear / Waste Water Technology / Water Management / Water Pollution Control / Wear rate / Wear resistance