5 years ago

Metastable Zr–Nb alloys for spinal fixation rods with tunable Young’s modulus and low magnetic resonance susceptibility

Metastable Zr–Nb alloys for spinal fixation rods with tunable Young’s modulus and low magnetic resonance susceptibility
Good ductility, low magnetic susceptibility, and tunable Young’s modulus are highly desirable properties for materials usage as spinal fixation rods. In this study, the effects of niobium content on the microstructure, magnetic susceptibility, and mechanical properties of Zr–xNb (13x≤23wt%) alloys were investigated. For the Zr–15Nb and Zr–17Nb alloys, a remarkable increase in Young’s modulus was achieved due to the occurrence of deformation-induced ω phase transformation. This was the result of the competition of two factors associated with the Nb content: an increase of the stability of β phase and a decrease of the amount of athermal ω phase with increasing Nb content. When the Nb content was 15% or 17%, the amount of deformation-induced ω phase was maximum. Moreover, the magnetic susceptibility decreased with the deformation-induced βω phase transformation, and the Zr–17Nb alloy with apparent kink bands exhibited a smaller amount of springback than the Zr–15Nb alloy with {332} 〈113〉 mechanical twins. Furthermore, the ions released from the Zr–xNb alloys in accelerated immersion tests were at a very low level. The combination of low initial Young’s modulus, and its remarkable variation induced by deformation, low magnetic susceptibility, good ductility, and smaller springback make the Zr–17Nb alloy a potential candidate for spinal fixation rods. Statement of Significance For the rods of spinal fixation devices, it is important but difficult to lower the springback for bending formativeness while keeping the low initial Young′s modulus for biocompatibility and lower the magnetic susceptibility for postoperative examination simultaneously. In this study, Zr–17Nb alloy was successfully developed via deformation-induced ω phase transformation during loading, simultaneously meeting the abovementioned properties for spinal fixation rods.

Publisher URL: www.sciencedirect.com/science

DOI: S1742706117305263

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.