Název:
High Temperature Fatigue Behaviour of Third Generation of TiAl Alloys
Autoři:
Obrtlík, Karel ; Kruml, Tomáš Typ dokumentu: Příspěvky z konference Konference/Akce: International Colloquim Mechanical Fatigue of Materials - ICMFM /16./, Brno (CZ), 2012-09-24 / 2012-09-26
Rok:
2012
Jazyk:
eng
Abstrakt: Low cycle fatigue properties of lamellar TiAl with 7.8 at.% Nb were studied at four temperatures: room temperature, 700, 750 and 800 °C. Up to 750 °C, stable cyclic behaviour is observed while cyclic softening is characteristic for 800°C. The strength of the alloy is still high even at 800 °C. The TEM observation did not reveal any substantial changes in the microstructure due to the cycling at RT. At 750 °C, the lamellar structure was in some places destroyed by cyclic plasticity and pure g-phase islands with high density of dislocation debris were formed. At 800 °C, the domains without lamellar structure cover about 10% of inspected volume and are almost dislocation free. The results show that the diffusion processes leading to vanishing of small prizmatic dislocation loops start to operate between 750 and 800 °C. The destruction of lamellar microstructure and annealing of dislocation debris is the reason for cyclic softening at 800 °C.
Klíčová slova:
high temperature fatigue; lamellar microstructure; TEM; TiAl Číslo projektu: ED1.1.00/02.0068, GAP107/11/0704 (CEP) Poskytovatel projektu: GA MŠk, GA ČR Zdrojový dokument: Proceedings of the 16th International Colloquium Mechanical Fatigue of Materials, ISBN 978-80-87434-05-5
Instituce: Ústav fyziky materiálů AV ČR
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Informace o dostupnosti dokumentu:
Dokument je dostupný v příslušném ústavu Akademie věd ČR. Původní záznam: http://hdl.handle.net/11104/0216786