Rapid fabrication of function-structure-integrated NiTi alloys: Towards a combination of excellent superelasticity and favorable bioactivity

Research output: Contribution to journalArticleResearchpeer-review

Authors

  • Lei Zhang
  • Zhengyuan He
  • Jun Tan
  • Yuqin Zhang
  • Mihai Stoica
  • Konda Gokuldoss Prashanth
  • Y. H. Jiang

External Organisational units

  • Kunming University of Science and Technology
  • Engineering Technology Research Center of Titanium Products and Application of Yunnan Province
  • Politehnica University of Timisoara
  • Erich Schmid Institute of Materials Science
  • Leibniz Institute for Solid State and Materials Research, Dresden

Abstract

Porous NiTi has brought new expectations to the field of orthopaedic implants due to its excellent mechanical properties such as high strength and superelasticity together with good biocompatibility. In order to facilitate the surrounding bone tissue ingrowth into the implanted porous alloy, reasonably large sized pores and a high amount of porosity are required. There is, however, a major challenge for clinical applications: the higher the porosity, the worse are the mechanical properties and the superelasticity. In this work, therefore, function-structure-integrated NiTi alloys consisting of a central solid and an outer porous layer were fabricated by spark plasma sintering (SPS). When sintered at 750 °C, the NiTi alloy with 14% porosity in the inner part and 49% porosity as well as 350 μm average pore size in the outer layer exhibits an exceptionally high compressive strength (∼1375 MPa), together with an excellent superelastic recovery strain (>4%) and favorable cellular affinity (ROS1728 osteoblasts). Altogether, this work provides a strategy to design materials with function-structure integration and suggests that properly designed function-structure integrated NiTi alloys may be promising as advanced bone implants.

Details

Original languageEnglish
Pages (from-to)1-13
Number of pages13
JournalIntermetallics
Volume82.2017
Issue numberMarch
Early online date29 Nov 2016
DOIs
Publication statusPublished - 1 Mar 2017