Creep and microstructure of the alloy Fe-30 at. % Al with addition of 5 at. % Zr

0398608 - ÚFM 2014 RIV SK eng C - Conference Paper (international conference)
Dobeš, Ferdinand - Kratochvíl, P. - Kejzlar, P.
Creep and microstructure of the alloy Fe-30 at. % Al with addition of 5 at. % Zr.
Degradácia konštrukčných materialov 2013. Žilina: Žilinská univerzita, 2013 - (Chalupová, M.; Hurtalová, L.), s. 7-12. ISBN 978-80-554-0741-8.
[Degradácia konštrukčných materialov 2013. Zuberec (SK), 04.09.2013-06.09.2013]
R&D Projects: GA ČR(CZ) GAP108/12/1452
Institutional support: RVO:68081723
Keywords : Iron aluminides * creep * Laves phase * annealing
Subject RIV: JG - Metallurgy

Compressive creep of alloy based on Fe-30 at. % Al with addition of 5.2 at. % zirconium was studied at temperatures from 650 to 900 °C. The alloy was tested in two different states: (i) cast and (ii) annealed at 1000 °C for 50 hours. The microstructure of as cast alloy consisted of matrix (alpha/B2/D03) and fine lamellar eutectic composed from lambda and (alpha/B2/D03). The eutectic decomposed during annealing at 1000 °C into lambda and tau phases. Stress exponents and activation energies were estimated. The values of the stress exponent n can be explained by dislocation motion controlled by climb. Creep exposure at 900 °C for about 50 hours is probably sufficient for attainment the three-phase structure because the same microstructure was observed after creep at 900 °C, in both as-cast and annealed states. In contrast, creep expositions at 650 °C and 700 °C did not influence the appearance of microstructure.
Permanent Link: http://hdl.handle.net/11104/0226208