Fracture behavior of novel biomedical Ti-based high entropy alloys under impact loading

Gurel S., Yagci M. B., Canadinc D., Gerstein G., Bal B., Maier H. J.

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, vol.803, 2021 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 803
  • Publication Date: 2021
  • Doi Number: 10.1016/j.msea.2020.140456
  • Journal Name: MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, INSPEC, Metadex, Civil Engineering Abstracts
  • Keywords: High entropy alloy, Fracture, Impact response, TiTaHfNbZr, TiTaHfMoZr, TiTaHfNb, MECHANICAL-PROPERTIES, CORROSION BEHAVIOR, TI-6AL-4V ELI, MICROSTRUCTURE, RESISTANCE, TITANIUM, TA, FE, IMPURITIES, STABILITY
  • Abdullah Gül University Affiliated: Yes

Abstract

This paper focuses on the mechanical properties and fracture behavior of newly developed body-centered-cubic structured TiTaHfNb, TiTaHfNbZr and TiTaHfMoZr high entropy alloys (HEAs) under impact loading as part of an effort to evaluate their potential utility as implant materials. The experimental findings showed all three Ti based HEAs have lower Young's modulus as compared to the conventionally used implant materials. Fractography analysis revealed that the TiTaHfNb HEA demonstrated significant ductility with the highest energy absorption capacity, while the TiTaHfNbZr and the TiTaHfMoZr alloys exhibited mixed mode fracture with relatively low ductility. Specifically, the reduction of ductility and energy absorption capacity under impact loading was attributed to the addition of Zr and Mo into Ti-based HEA system, which facilitates formation of additional dislocations in the microstructure due to increased lattice distortion. The current findings demonstrate that, from a mechanical point of view, the TiTaHfNb HEA could be considered as an alternative implant material for applications demanding high wear and corrosion resistance, such as hip or knee implants, and thus, warrant further investigation of the biomedical performance of this alloy.Y