Effect of non-glide components of the stress tensor on deformation behavior of bcc transition metals
In this paper the authors demonstrate by atomic computer simulation that the non-Schmid slip behavior in bcc metals is a direct consequence of the non-planar core structure of 1/2<111> screw dislocations and their response to the applied stress tensor. The analysis has been carried out in detail for tantalum using the Finnis-Sinclair type central force many-body potentials. Two distinct non-Schmid effects have been discerned. The first is twinning-antitwinning slip asymmetry on {l{underscore}brace}112{r{underscore}brace} planes. This is an intrinsic property of the bcc structure and depends on the sense of the applied glide stress. The second non-Schmid effect is extrinsic and is controlled by the non-glide shear stresses perpendicular to the total Burgers vector on {l{underscore}brace}110{r{underscore}brace} planes into which the stress-free core of screw dislocations spread.
- Research Organization:
- Kyoto Univ. (JP)
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 20014963
- Resource Relation:
- Conference: Multiscale Modeling of Materials, Boston, MA (US), 11/30/1998--12/03/1998; Other Information: Single article reprints are available through University Microfilms Inc., 300 North Zeeb Rd., Ann Arbor, Michigan 48106 (US); PBD: 1999; Related Information: In: Multiscale modeling of materials. Materials Research Society symposium proceedings: Volume 538, by Bulatov, V.V.; Diaz de la Rubia, T.; Phillips, R.; Kaxiras, E.; Ghoniem, N. [eds.], 607 pages.
- Country of Publication:
- United States
- Language:
- English
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