Strange behavior of dislocations of a certain type: Self-locking
- Authors: Greenberg B.A.1, Ivanov M.A.2
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Affiliations:
- Institute of Metal Physics, Ural Branch
- Kurdjumov Institute of Physical Metallurgy
- Issue: Vol 2016, No 4 (2016)
- Pages: 266-285
- Section: Physical Foundations of Strength and Plasticity
- URL: https://journals.rcsi.science/0036-0295/article/view/170430
- DOI: https://doi.org/10.1134/S0036029516040091
- ID: 170430
Cite item
Abstract
The results of studying the self-locking of dislocations, namely, the transformation of glissile dislocations into blocked dislocations in the absence of an applied stress, are generalized. The existence of selflocking is theoretically grounded and experimentally proved via the observation of dislocation extension along a preferred direction upon loading-free heating after preliminary plastic deformation. The following concept is developed to explain the experimental results: an effective force appears in the case of a two-valley dislocation potential relief; it is proportional to the difference between the valley depths and causes the transformation of a dislocation into an indestructible barrier. The temperature anomaly of yield strength and the dislocation self-locking are shown to have the same nature—a two-valley dislocation potential relief. Both effects were observed in Ni3Al- and TiAl-type intermetallics and a pure metal (magnesium).
About the authors
B. A. Greenberg
Institute of Metal Physics, Ural Branch
Author for correspondence.
Email: bella@imp.uran.ru
Russian Federation, ul. S. Kovalevskoi 18, Yekaterinburg, 620990
M. A. Ivanov
Kurdjumov Institute of Physical Metallurgy
Email: bella@imp.uran.ru
Ukraine, bul’v. Akad. Vernadskogo 36, Kiev, 03680