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Title: First-principles study of the α - ω phase transformation in Ti and Zr coupled to slip modes

 [1];  [1];  [1]
  1. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
Publication Date:
Sponsoring Org.:
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Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 123; Journal Issue: 4; Related Information: CHORUS Timestamp: 2018-01-30 11:58:14; Journal ID: ISSN 0021-8979
American Institute of Physics
Country of Publication:
United States

Citation Formats

Kumar, Anil, Bronkhorst, Curt A., and Lookman, Turab. First-principles study of the α - ω phase transformation in Ti and Zr coupled to slip modes. United States: N. p., 2018. Web. doi:10.1063/1.5007074.
Kumar, Anil, Bronkhorst, Curt A., & Lookman, Turab. First-principles study of the α - ω phase transformation in Ti and Zr coupled to slip modes. United States. doi:10.1063/1.5007074.
Kumar, Anil, Bronkhorst, Curt A., and Lookman, Turab. 2018. "First-principles study of the α - ω phase transformation in Ti and Zr coupled to slip modes". United States. doi:10.1063/1.5007074.
title = {First-principles study of the α - ω phase transformation in Ti and Zr coupled to slip modes},
author = {Kumar, Anil and Bronkhorst, Curt A. and Lookman, Turab},
abstractNote = {},
doi = {10.1063/1.5007074},
journal = {Journal of Applied Physics},
number = 4,
volume = 123,
place = {United States},
year = 2018,
month = 1

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on January 30, 2019
Publisher's Accepted Manuscript

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  • We use first-principles density functional theory to study the preferred modes of slip in the high-pressure ω phase of Zr. The generalized stacking fault energy surfaces associated with shearing on nine distinct crystallographic slip modes in the hexagonal ω-Zr crystal are calculated, from which characteristics such as ideal shear stress, the dislocation Burgers vector, and possible accompanying atomic shuffles, are extracted. Comparison of energy barriers and ideal shear stresses suggests that the favorable modes are prismatic < c >, prismatic-II <101¯0> and pyramidal-II < c+a >, which are distinct from the ground state hexagonal close packed α phase of Zr.more » Operation of these three modes can accommodate any deformation state. The relative preferences among the identified slip modes are examined using a mean-field crystal plasticity model and comparing the calculated deformation texture with the measurement. In conclusion, knowledge of the basic crystallographic modes of slip is critical to understanding and analyzing the plastic deformation behavior of ω-Zr or mixed α-ω phase-Zr.« less
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