Influence of temperature and strain rate on the deformation and damage mechanisms of oxide dispersion strengthened ferritic steels
Autor: | Frédéric Mompiou, Alexis Deschamps, J. Garnier, F. Barcelo, P. Wident, M. Dadé, J. Malaplate |
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Rok vydání: | 2018 |
Předmět: |
010302 applied physics
Materials science Uniaxial tension Oxide 02 engineering and technology Plasticity Strain rate 021001 nanoscience & nanotechnology 01 natural sciences chemistry.chemical_compound Deformation mechanism chemistry Powder metallurgy 0103 physical sciences Hardening (metallurgy) General Materials Science Composite material Dislocation 0210 nano-technology |
Zdroj: | Materialia. 4:585-594 |
ISSN: | 2589-1529 |
DOI: | 10.1016/j.mtla.2018.11.016 |
Popis: | Deformation and damage mechanisms of Fe-14Cr based oxide dispersion strengthened (ODS) steels have been investigated through a multi scale approach on model materials elaborated by powder metallurgy Uniaxial tensile behavior was studied from room temperature to 800 °C at several strain rates. Furthermore, the plasticity of Fe-14Cr ODS steels has been analyzed at the grain scale by in situ transmission electron microscopy (TEM) straining experiments between room temperature and 650 °C, evidencing a clear evolution with temperature of the dislocation motion. The evolution of yield stress with temperature has been separated into three domains, which can be explained by changes of deformation mechanisms. At low temperatures, the hardening is associated to the pining of dislocations on nano-oxides whereas dislocations motion is thermally activated at higher temperatures. At high temperatures, a competition between intra- and inter-granular mechanisms is observed. The transition in damage mechanism, related to the change of deformation mode, explains the observed reduction of ductility. |
Databáze: | OpenAIRE |
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