Effect of heat-treatment on the microstructure and fatigue properties of lamellar γ-TiAl alloyed with Nb, Mo and/or C

0524225 - ÚFM 2021 RIV CH eng J - Článek v odborném periodiku
Chlupová, Alice - Heczko, Milan - Obrtlík, Karel - Dlouhý, Antonín - Kruml, Tomáš
Effect of heat-treatment on the microstructure and fatigue properties of lamellar γ-TiAl alloyed with Nb, Mo and/or C.
Materials Science and Engineering A Structural Materials Properties Microstructure and Processing. Roč. 786, JUN (2020), č. článku 139427. ISSN 0921-5093. E-ISSN 1873-4936
Grant CEP: GA MŠMT(CZ) LQ1601
Institucionální podpora: RVO:68081723
Klíčová slova: TiAl alloys * Heat treatment * Microstructure * Mechanical properties * Fatigue
Obor OECD: Materials engineering
Impakt faktor: 5.234, rok: 2020
Způsob publikování: Omezený přístup
https://doi.org/10.1016/j.msea.2020.139427

In this study, the effect of the heat-treatment was investigated on five different γ-TiAl compositions alloyed with
7 at.% of Nb and varying content of Mo and C. Mechanical properties of as-received and heat-treated alloys were
assessed using tensile and symmetrical tension-compression cyclic loading at room temperature and 750 °C.
Scanning electron microscopy, electron back-scatter and X-ray powder diffraction, as well as high-resolution
scanning transmission electron microscopy, were used to characterize microstructural changes induced by the
heat-treatments. Modification of lamellar substructure in terms of a significant decrease of lamellar spacing
directly affects the mobility of dislocations. Together with the change in the phase composition of the alloys, it is
the key mechanism leading to the improvement of the ultimate tensile stress, fracture plastic strain as well as
higher cyclic strength. It also increases the cumulative plastic strain in cyclic loading both at ambient and
elevated temperatures.
Trvalý link: http://hdl.handle.net/11104/0309678