Publication detail
Effect of Cyclic Heat Treatment on Cast Structure of TiAl Alloy
PETRENEC, M. VRASPÍROVÁ, E. NĚMEC, K. HECZKO, M.
Czech title
Vliv cyklického tepelného zpracování na litou strukturu TiAl slitiny
English title
Effect of Cyclic Heat Treatment on Cast Structure of TiAl Alloy
Type
journal article - other
Language
en
Original abstract
The subject of the article is focused on the refining of the cast structure of gamma TiAl-2Nb alloy using cyclic heat treatment and on the analysis of the grain refining mechanism. Microstructure evolution after applied cycles of heat treatment was characterized using light, laser and electron microscopy and using microhardness tests. Application of five heat treatment cycles during which two phase transformations (eutectoid and alpha-recrystallization reactions) repeatedly took place resulted in refining of the cast columnar structure. The mean grain-lamellar colony size 512 mm was transformed to fully lamellar structure containing gamma and alpha2 phases having the mean grain size 229 mm. Lamellae thickness of gamma was not changed while the thickness of alpha2 phase decreased to 78 nm. Refining of alpha2 phase resulted in the increase of the microhardness by 20 %. The recrystallized cast structure obtained by cyclic heat treatment and the knowledge on the mechanisms of the refining the structure were compared and discussed with the literature data.
Czech abstract
Tato studie je zaměřena na zušlechtění lité struktury slitiny gamma TiAl-2Nb prostřednictvím cyklického tepelného zpracování a na analýzu mechanismu zjemnění zrn. Vývoj mikrostruktury po aplikaci cyklického tepelného zpracování byl charakterizován prostřednictvím světelné, laserové a elektronové mikroskopie a také použitím testů mikrotvrdosti. Rekrystalizovaná litá struktura získaná cyklickým tepelným zpracováním a znalost mechanismů zušlechtění struktury byly porovnány a diskutovány se známou literaturou.
English abstract
The subject of the article is focused on the refining of the cast structure of gamma TiAl-2Nb alloy using cyclic heat treatment and on the analysis of the grain refining mechanism. Microstructure evolution after applied cycles of heat treatment was characterized using light, laser and electron microscopy and using microhardness tests. Application of five heat treatment cycles during which two phase transformations (eutectoid and alpha-recrystallization reactions) repeatedly took place resulted in refining of the cast columnar structure. The mean grain-lamellar colony size 512 mm was transformed to fully lamellar structure containing gamma and alpha2 phases having the mean grain size 229 mm. Lamellae thickness of gamma was not changed while the thickness of alpha2 phase decreased to 78 nm. Refining of alpha2 phase resulted in the increase of the microhardness by 20 %. The recrystallized cast structure obtained by cyclic heat treatment and the knowledge on the mechanisms of the refining the structure were compared and discussed with the literature data.
Keywords in Czech
TiAl slitina, cyklické tepelné zpracování, zušlechtěná litá struktura, nesouvislé zdrsňování, mikrotvrdost
Keywords in English
TiAl alloy, cyclic heat treatment, refined cast structure, discontinuous coarsening, microhardness
RIV year
2013
Released
10.09.2013
Publisher
Trans Tech Publications
Location
Switzerland
ISSN
1013-9826
Volume
586
Number
9
Pages from–to
222–225
Pages count
4
BIBTEX
@article{BUT108924,
author="Martin {Petrenec} and Eva {Vraspírová} and Karel {Němec} and Milan {Heczko},
title="Effect of Cyclic Heat Treatment on Cast Structure of TiAl Alloy",
year="2013",
volume="586",
number="9",
month="September",
pages="222--225",
publisher="Trans Tech Publications",
address="Switzerland",
issn="1013-9826"
}