Crystallinity, surface morphology, and chemical composition of the recast layer and rutile-TiO2 formation on Ti-6Al-4V ELI by wire-EDM to enhance biocompatibility

  • Saadman Sakib RahmanEmail author
  • Md. Zurais Ibne Ashraf
  • M. S. Bashar
  • M. Kamruzzaman
  • A. K. M. Nurul Amin
  • M. M. Hossain


In this study, the surface morphology, chemical composition, and crystallography of the recast layer on wire electrical discharge machining (wire-EDM) modified Ti-6Al-4V ELI were investigated through scanning electron microscopy, backscattered electron imaging, energy-dispersive x-ray spectroscopy, and x-ray diffraction. The characteristics of the two tailored cutting strategies, namely, main cut and finish trim cut, were evaluated in terms of micro-cracks, micro-pores, recast layer thickness (RLT), surface roughness (SR), phase transition, and micro-hardness. In addition, the relative changes of the SR, RLT, and kerf width were demonstrated with regard to peak current and pulse spacing. Noticeably fewer amounts of micro-cracks, micro-voids, remarkable truncation of RLT and SR, and nanoporous structure were attained at finish trim cut mode. It was also found out that an α → α′ + rutile-TiO2 phase transition occurred on the recast layer of wire-EDM modified sample at finish trim cut. Furthermore, recast layer showed higher micro-hardness compared to that of the heat-affected zone and bulk material. In essence, the wire-EDM finish trim cut treatment is a potential technology to feasibly enhance the biocompatibility for Ti-6Al-4V ELI alloy through the formation of rutile-TiO2 and amelioration of the surface morphology.


Ti-6Al-4V ELI Wire-EDM Recast layer X-ray diffraction Rutile-TiO2 Biocompatibility 


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Copyright information

© Springer-Verlag London Ltd. 2017

Authors and Affiliations

  • Saadman Sakib Rahman
    • 1
    Email author
  • Md. Zurais Ibne Ashraf
    • 1
  • M. S. Bashar
    • 2
  • M. Kamruzzaman
    • 3
  • A. K. M. Nurul Amin
    • 1
  • M. M. Hossain
    • 3
  1. 1.Department of Mechanical and Production EngineeringAhsanullah University of Science and TechnologyDhakaBangladesh
  2. 2.Institute of Fuel Research and Development, Bangladesh Council of Scientific and Industrial ResearchDhakaBangladesh
  3. 3.Department of Mechanical EngineeringDhaka University of Engineering and TechnologyGazipurBangladesh

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