Peculiarities of Plastic Deformation and Failure of Nanoparticles of B.C.C. Transition Metals
| Periodical | Materials Science Forum (Volumes 567 - 568) |
|---|---|
| Main Theme | Materials Structure & Micromechanics of Fracture V |
| Edited by | Pavel Šandera |
| Pages | 65-68 |
| DOI | 10.4028/www.scientific.net/MSF.567-568.65 |
| Citation | Sergiy Kotrechko et al., 2007, Materials Science Forum, 567-568, 65 |
| Online since | December, 2007 |
| Authors | Sergiy Kotrechko, O. Filatov, O. Ovsjannikov |
| Keywords | "Orthorhombic" Path, B.C.C. Transition Metals, Failure, Nanoparticle, Plastic Deformation |
| Price | US$ 28,- |
Atomic mechanisms of the beginning of plastic deformation and failure initiation in nanoparticles of b.c.c. transition metals are presented in this report. It is shown that strength level of nanoparticles of b.c.c. transition metals is pre-determined by the lattice instability within the local region of the crystal. At uniaxial tension even at low temperatures perfect crystal becomes unstable to shear („orthorhombic“ path), i.e. local shear instability is the main mechanism of stress relaxation in nanoparticles of b.c.c. metals. Specific features of local instability of nanoparticle under hydrostatic tension are considered. A model of the temperature dependence of strength is offered. It is shown that nanoparticle strength decreases as square root function of temperature with temperature growth. Just this is essential difference of the temperature dependence of nanoparticle strength from the same for “ordinary” single- and polycrystals.
