0386294 - ÚFM 2013 RIV JP eng C - Konferenční příspěvek (zahraniční konf.)
Král, Petr - Dvořák, Jiří - Kvapilová, Marie - Svoboda, Milan - Sklenička, Václav
Influence of Grain Size on Creep Behavior of Copper Processed by ECAP.
Creep and Fracture of Engineering Materials and Structure. Sendai: The Japan Institute of Metals, 2012, s. 460-464. ISBN 978-4-88903-407-3.
[International Conference on Creep and Fracture of Engineering Materials and Structures (JIMIS 11) /12./. Kyoto (JP), 27.05.2012-31.05.2012]
Grant CEP: GA ČR GPP108/10/P469
Institucionální podpora: RVO:68081723
Klíčová slova: ultrafine-grained microstructure * equal-channel angular pressing (ECAP) * grain boundary sliding * copper
Kód oboru RIV: JJ - Ostatní materiály

Experiments were conducted to determine an effect of ECAP pressing on the creep behavior of pure Cu. The ECAP pressing was performed at room temperature by route Bc. Constant load creep tests in tension were conducted at 373, 473 and 573 K under different stresses. The values of the stress exponent n of the minimum creep rate for ultrafine-grained (UFG) and coarse-grained material were determined. The results demonstrate that the n of coarse-grained material increases from the value n ~ 6 measured at 573 K to the value of n ~ 14 determined at 373 K. However, the values of stress exponent n of UFG material were about 6 at 373, 473 and 573 K over relatively wide range of strain rates. Microstructure of samples was characterized by transmission electron microscope (TEM) and scanning electron microscope (SEM) equipped with the electron backscatter unit (EBSD). It was found that the change of grain size and number of high-angle grain boundaries in the microstructure influence the transition from power law behavior region to the power law breakdown and that creep behavior of UFG Cu is influenced by grain boundary sliding and cavitation.
Trvalý link: http://hdl.handle.net/11104/0215948