MACHINABILITY OF PURE METALS BY ELECTRICAL DISCHARGE MACHINING

  • Pedro Miguel Horta Sousa IDMEC, Departamento de Engenharia Mecânica, Instituto Superior Técnico, Universidade de Lisboa, Portugal
  • Ivo Manuel Ferreira de Bragança Departamento de Engenharia Mecânica, Instituto Superior de Engenharia de Lisboa, Portugal https://orcid.org/0000-0001-5409-619X
  • Abílio Manuel Pinho de Jesus Departamento de Engenharia Mecânica, Faculdade de Engenharia da Universidade do Porto, Portugal
  • José Duarte Ribeiro Marafona Departamento de Engenharia Mecânica, Faculdade de Engenharia da Universidade do Porto, Portugal https://orcid.org/0000-0001-9173-0962
  • Pedro Alexandre Rodrigues Carvalho Rosa IDMEC, Departamento de Engenharia Mecânica, Instituto Superior Técnico, Universidade de Lisboa, Portugal
Keywords: electrical discharge machining, crater morphology, machinability, pure metals

Abstract

Electrical discharge machining (EDM) involves the generation of micro-plasmas subjected to high temperature and pressure to promote the material removal. Hence, to understand the material removal mechanism it is of great importance the knowledge of the interaction plasma-solid. Knowing how physical and chemical properties of materials affect heat transfer at the electrode surface, how this eventually affects electrical properties of the plasma channel over the discharge time are key issues to achieve a better understanding of this machining technology. This research attempts to provide some answers to these issues by means of single plasma discharge tests under laboratory-controlled conditions carried out on pure and low-alloyed materials in favour of comprehensiveness and forthcoming numerical modelling. These results demonstrate that material eroded volume is correlated with process operating parameters and that crater morphology has presented a more regular shape in pure metals than in engineering materials. The machinability index of the materials under study has been determined by calculations of the eroded volume and electrical power measures. Further to the low predictability of the models presented in literature, it was also proposed a basic conceptual model referring to the morphology of the eroded craters.

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Published
2018-03-01
How to Cite
Sousa, P. M. H., Bragança, I. M. F. de, Jesus, A. M. P. de, Marafona, J. D. R., & Rosa, P. A. R. C. (2018). MACHINABILITY OF PURE METALS BY ELECTRICAL DISCHARGE MACHINING. Revista Produção E Desenvolvimento, 4(1), 54-67. https://doi.org/10.32358/rpd.2018.v4.311
Section
Associated Editors