Oxygen-dislocation interaction in titanium from first principles. (15th March 2019)

• Record Type: Journal Article
• Authors: Chaari, Nermine; Rodney, David; Clouet, Emmanuel
• Is Part Of: Scripta materialia. Number 162(2019)
• Page Start: 200
• Page End: 203
• Publication Date: 2019-03-15
• Subjects: Dislocation -- Plasticity -- Titanium -- Oxygen -- Hardening; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2018.11.025
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: The interaction between screw dislocations and oxygen interstitial atoms is studied with ab initio calculations in hexagonal close-packed titanium. Our calculations evidence a strong repulsion when the solute atoms are located in the dislocation glide plane, leading to spontaneous cross-slip, which allows the dislocation to bypass the atomic obstacle. This avoidance process explains several experimental observations in titanium in presence of oxygen: (1) a larger lattice friction against screw dislocation motion, (2) a reduction of the dislocation glide distance in prismatic planes and (3) an enhancement of cross-slip in pyramidal planes. Graphical Abstract: