Study of nanometer-scaled lamellar microstructure in a Ti-45Al-7.5Nb alloy - Experiments and modeling

Autor(en)

Franz Dieter Fischer, Thomas Waitz, Christina Scheu, Limei Cha, Gerhard Dehm, Thomas Antretter, Helmut J. Clemens

Abstrakt

Quenching of Ti-45 at%Al-7.5 at%Nb from the single alpha-phase region to room temperature followed by aging below the eutectoid temperature leads to the precipitation of ultra-fine gamma-TiAl lamellae. In addition to an extensive experimental program, reported by Cha et al. in Intermetallics 16 (2008) 868-875, in this work a micromechanical and thermodynamical model is presented for the formation of gamma-TiAl lamellae within the alpha(2)-Ti3Al parent phase. A global transformation condition allows to predict a thickness to length ratio in accordance with experimental observations. Furthermore, a local transformation condition offers the basis for a kinetic law. The modeling concept can be applied to similar problems of combined diffusive and displacive phase transformations.

Organisation(en)

Physik Nanostrukturierter Materialien

Externe Organisation(en)

Montanuniversität Leoben, Ludwig-Maximilians-Universität München

Journal

Intermetallics

Band

18

Seiten

509-517

Anzahl der Seiten

9

ISSN

0966-9795

DOI

https://doi.org/10.1016/j.intermet.2009.09.012

Publikationsdatum

2010

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/cddbb733-c560-4b76-bb62-ac4c21e5892b