0542936 - ÚFM 2022 RIV GB eng J - Journal Article
Heczko, Milan - Mazánová, Veronika - Slone, Connor E. - Shih, M. - George, E.P. - Ghazisaedi, M. - Polák, Jaroslav - Mills, M. J.
Role of deformation twinning in fatigue of CrCoNi medium-entropy alloy at room temperature.
Scripta Materialia. Roč. 202, SEP (2021), č. článku 113985. ISSN 1359-6462. E-ISSN 1872-8456
Institutional support: RVO:68081723
Keywords : Medium- and high-entropy Alloys * Deformation twinning * Fatigue * Crack initiation * Crack initiation
OECD category: Materials engineering
Impact factor: 6.302, year: 2021 ; AIS: 1.221, rok: 2021
Method of publishing: Limited access
Result website:
https://www.sciencedirect.com/science/article/pii/S1359646221002657?via%3DihubDOI: https://doi.org/10.1016/j.scriptamat.2021.113985

Cylindrical specimens of CrCoNi alloy with electropolished surfaces were subjected to constant total strain amplitude low cycle fatigue. The alloy exhibited an initial period of cyclic hardening followed by cyclic softening until failure occurred. At the end of hardening stage at the peak of cyclic stress, well-developed persistent slip markings (PSMs) consisting of extrusions and intrusions were associated with thin deformation twins. A sophisticated experimental workflow was designed to extract information from the surface and the bulk of tested material. A combination of SEM, EBSD, ECCI, FIB and HR-STEM was used to study the internal structure and the surface profiles around the deformation twins, which were produced during the initial period of cyclic loading. Furthermore, localized cyclic plastic strain and stress concentrations near deformation twins led not only to early, well-developed PSMs, but also to the activation of TWIP and TRIP plasticity even at low macroscopic stress amplitudes.
Permanent Link: http://hdl.handle.net/11104/0320815