Investigating the electronic origins of the repulsion between substitutional and interstitial solutes in hcp Ti

N. S. Harsha Gunda, Carlos G. Levi, and Anton Van der Ven
Phys. Rev. Materials 5, 073604 – Published 7 July 2021
PDFHTMLExport Citation

Abstract

The high solubility of oxygen in Ti, Zr, and Hf makes it difficult to stabilize protective oxide scales on their surfaces as the subsurface regions can serve as boundless sinks that continuously dissolve oxygen. Alloying elements are crucial to reduce the oxygen solubility and diffusivity within early transition metals. Past studies have shown that most substitutional alloying additions to titanium repel interstitial oxygen. Here we use first-principles calculations to show that this repulsion is short ranged and explore several factors that are likely responsible for the repulsive interaction. Calculations of Bader charges suggest the existence of short-range Coulomb interactions due to the accumulation of charge on the substitutional solute and interstitial oxygen that is drawn from the Ti host. Misfit strains due to differences in the atomic radii of the solutes and Ti are also found to play a role. We identify a unique hybridization phenomenon between dissolved substitutional elements and interstitial oxygen within hcp Ti that leads to a repulsive interaction at short distances, similar to that between closed-shell atoms, which is especially pronounced for Al and Si solutes.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
4 More
  • Received 13 March 2021
  • Accepted 22 June 2021

DOI:https://doi.org/10.1103/PhysRevMaterials.5.073604

©2021 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

N. S. Harsha Gunda, Carlos G. Levi, and Anton Van der Ven*

  • Materials Department, University of California, Santa Barbara, California 93117, USA

  • *avdv@ucsb.edu

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 5, Iss. 7 — July 2021

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Materials

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×