Název: Microstructure and Anisotropy of Creep in Ti-46Al-2W-0.5Si Castings
Autoři: Dlouhý, Antonín ; Kuchařová, Květa ; Svoboda, Milan ; Válek, Robert ; Březina, Josef
Typ dokumentu: Příspěvky z konference
Konference/Akce: International Conference on Materials structure and Micromechanics of Fracture /3./, Brno (CZ), 2001-06-27 / 2001-06-29
Rok: 2001
Jazyk: eng
Abstrakt: The present study investigates microstructure and creep behaviour of the cast alloy Ti-46A1-2W-0.5Si (at-%) at temperatures 700, 750 and 800°C and applied stresses between 250-420 MPa. Solidification of the alloy during precision casting is associated with two processes: (i) the growth of the [0001].alpha. oriented columnar grains from the mould wall into the cast interior and (ii) the enrichment of the central part of the cast with aluminium. The first process results in a fully lamellar microstructure where lamellae are preferentially oriented parallel to the cast surface. The second process contributes to the development of the duplex microstructure in the central part of the cast. It is shown that distinct microstructural types in different regions of the cast result in different creep strengths. Specimens taken from inside of the cast and oriented parallel to the cast bar axis exhibited the lowest creep strength while similarly oriented specimens cut from the fully lamellar region near the cast surface were the strongest. The third type of the creep specimens cut out of the central region of the cast and oriented perpendicular to the cast bar axis showed the intermediate creep strength. The observed variations of the creep strength are associated with the preferential orientation of the lamellas and with the fraction of equiaxed .gamma.-grains in the duplex regions of the cast.
Klíčová slova: gamma-TiAl; gas turbine; intermetallics
Číslo projektu: CEZ:AV0Z2041904 (CEP), OC 522.100, IBS2041001 (CEP)
Poskytovatel projektu: GA MŠk, GA AV ČR
Zdrojový dokument: MATERIAL STRUCTURE & MICROMECHANICS OF FRACTURE PROCEEDINGS MSMF-3, ISBN 80-214-1892-3

Instituce: Ústav fyziky materiálů AV ČR (web)
Informace o dostupnosti dokumentu: Dokument je dostupný v příslušném ústavu Akademie věd ČR.
Původní záznam: http://hdl.handle.net/11104/0074516

Trvalý odkaz NUŠL: http://www.nusl.cz/ntk/nusl-26439


Záznam je zařazen do těchto sbírek:
Věda a výzkum > AV ČR > Ústav fyziky materiálů
Konferenční materiály > Příspěvky z konference