Glide and cross-slip of a-dislocations in Zr and Ti

Slip systems involving dislocations with Burgers vectors have been studied in hexagonal close packed Zr and Ti, by means of in situ straining experiments in a transmission electron microscope, at various temperatures and as a function of resolved shear stress. The results show that Zr and Ti are ver...

Full description

Saved in:
Bibliographic Details
Published in:Acta materialia 2018-08, Vol.155, p.23-34
Main Authors: Caillard, D., Gaumé, M., Onimus, F.
Format: Article
Language:English
Subjects:
Condensed Matter
Dislocations
In situ straining experiments
Materials Science
Physics
Titanium
Transmission electron microscope
Zirconium
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Slip systems involving dislocations with Burgers vectors have been studied in hexagonal close packed Zr and Ti, by means of in situ straining experiments in a transmission electron microscope, at various temperatures and as a function of resolved shear stress. The results show that Zr and Ti are very similar in many respects. Prismatic slip is activated at rather low resolved shear stresses, and is controlled by the interaction between mobile dislocations and solute atoms (presumably oxygen). Pyramidal slip requires substantially higher resolved shear stresses and is characterized by straight screw dislocations moving by a kink-pair mechanism. Basal slip is activated at and above room temperature, for resolved shear stresses equal or higher than those in the prismatic planes. The slip traces are always wavy, presumably due to intensive cross slip from basal to prismatic planes. It also involves straight screw dislocations moving by a kink-pair mechanism. These microscopic observations are discussed in the light of some aspects of the mechanical behavior, in particular the increase of yield-stress at decreasing temperature and the discontinuity of activation area close to room temperature. [Display omitted]
ISSN:1359-6454
1873-2453
DOI:10.1016/j.actamat.2018.05.038