Parametric optimization of graphite powder-mixed electrical discharge machining of Ni-Cr dental alloy by response surface methodology


SAN E. S., ÖZERKAN H. B., SUBAŞI M., AYHAN E., MAVİ A., SALUNKHE S. S., ...More

SCIENTIFIC REPORTS, vol.15, no.1, 2025 (SCI-Expanded, Scopus) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 15 Issue: 1
  • Publication Date: 2025
  • Doi Number: 10.1038/s41598-025-32039-1
  • Journal Name: SCIENTIFIC REPORTS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, MEDLINE, Directory of Open Access Journals
  • Gazi University Affiliated: Yes

Abstract

In this study, the effects of machining parameters on material removal rate (MRR), electrode wear rate (EWR) and surface roughness (Ra) in the electrical discharge machining (EDM) of nickel-chromium-based alloy were investigated. Discharge current (I), pulse-on time (Ton), pulse-off time (Toff) and graphite powder concentration were selected as variable parameters in the study. An experimental setup was designed and manufactured for use in powder-mixed EDM experiments. Mathematical models were generated using response surface methodology (RSM), the most effective parameters on the results were determined and regression equations were obtained. Parameter optimization was performed with the highest MRR, lowest EWR, and lowest Ra performance targets. The ideal machining conditions were determined as I = 12.5 A, Ton=66 mu s, Toff=6 mu s and powder-mixed dielectric. Using the powder-mixed dielectric, 34.54% higher MRR, 20.01% lower EWR and 12.64% lower Ra were achieved on average. Using the created mathematical model, the result of the machining to be done with these parameters was predicted and the reliability of the model was tested by comparing the predicted results of the model and the results of the verification experiment.