Number of the records: 1
Deformation mechanisms of nanograined metallic polycrystals
- 1.
SYSNO ASEP 0358270 Document Type J - Journal Article R&D Document Type Journal Article Subsidiary J Článek ve WOS Title Deformation mechanisms of nanograined metallic polycrystals Author(s) Saada, G. (FR)
Kruml, Tomáš (UFM-A) RID, ORCIDNumber of authors 2 Source Title Acta Materialia. - : Elsevier - ISSN 1359-6454
Roč. 59, - (2011), s. 2565-2574Number of pages 10 s. Language eng - English Country GB - United Kingdom Keywords nanocrystalline materials ; grain boundary defects ; plastic deformation Subject RIV JJ - Other Materials CEZ AV0Z20410507 - UFM-A (2005-2011) UT WOS 000289131100001 DOI 10.1016/j.actamat.2010.12.035 Annotation This paper is an attempt to discuss the relevance of the physical concepts used to describe the plastic flow behaviour of a wide class of nanograined metallic polycrystals, by critically analyzing recent experimental observations on nanograined Ni and Cu. The paper focuses on the description of the elastic–plastic transition, and of the strain rate sensitivity. Using the generally accepted assumption that plastic flow results from dislocation nucleation at grain boundaries, it is shown that two deformation regimes must be distinguished: a nucleation- controlled mechanism at low strain rates, and a combined nucleation and propagation mechanism at high strain rates. At low deformation rates, the average nucleation rate is determined either from knowledge of the stress–strain curve, or from analysis of creep or relaxation kinetics. The strain rate sensitivity is shown to be related to the effect of stress on the nucleation rate. Workplace Institute of Physics of Materials Contact Yvonna Šrámková, sramkova@ipm.cz, Tel.: 532 290 485 Year of Publishing 2012
Number of the records: 1