0386069 - ÚFM 2013 RIV SK eng J - Článek v odborném periodiku
Lukáš, Petr - Kunz, Ludvík - Navrátilová, Lucie
Initiation of fatigue cracks in ultrafine-grained copper.
Kovové materiály. Roč. 50, č. 6 (2012), s. 407-419. ISSN 0023-432X. E-ISSN 1338-4252
Institucionální podpora: RVO:68081723
Klíčová slova: ultrafine-grained microstructure * fatigue * slip bands * microcrack initiation * grain coarsening
Kód oboru RIV: JL - Únava materiálu a lomová mechanika
Impakt faktor: 0.687, rok: 2012

Ultrafine-grained copper of commercial purity produced by ECAP technique was tested in fatigue in the range of lives from 5x103 to 2x1010 cycles. The fatigue strength of ultrafine-grained copper is by a factor of 2 higher than that of conventional-grained copper. The density of surface slip bands decreases with the decreasing stress amplitude and is extremely low in the very-high-cycle region. Fatigue microcracks were found to initiate in cyclic slip bands, which run across many grains in regions of near-by oriented grains. The very first fatigue damage in high-cycle and very-high-cycle regions consists in formation of cavities and elongated voids representing crack nuclei. No grain coarsening was observed either in bulk or in areas underneath the surface slip markings.
Trvalý link: http://hdl.handle.net/11104/0215366