Morphology evolution of Ti3AlC carbide precipitates in high Nb containing TiAl alloys

Wang L, Zenk C, Stark A, Felfer P, Gabrisch H, Göken M, Lorenz U, Pyczak F (2017)

Publication Type: Journal article

Publication year: 2017

Journal

Acta Materialia Elsevier

Book Volume: 137

Pages Range: 36-44

DOI: 10.1016/j.actamat.2017.07.018

Abstract

This work elucidates the morphology evolution of perovskite Ti3AlC carbides in a Ti-45Al-5Nb-0.75C alloy during ageing at 800 °C. The carbides in the g matrix are initially needle-shaped with their long axis parallel to the [001] lattice direction of the g matrix. After extended annealing, they decompose into small carbide sub-particles. By combining different transmission electron microscopy characterization methods and atom probe tomography it has been verified that the carbides first split into several parallel needles that are aligned along the [001]g lattice direction. Later these parallel needles further decompose into numerous small sub-particles, while the matrix phase region between the sub-particles crystallographically reorients. To the authors' knowledge this is the first work which demonstrates such a precipitate splitting process in a matrix with a tetragonal crystal structure. It is proposed that the decomposition into small sub-particles is energetically favourable owing to the elastic interaction energy between the split sub-particles.

Authors with CRIS profile

Carolin Zenk Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften) Peter Felfer Professur für Atom Probe Tomography Mathias Göken Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)

Additional Organisation(s)

Graduiertenkolleg 1896/2 In situ Mikroskopie mit Elektronen, Röntgenstrahlen und Rastersonden Interdisziplinäres Zentrum, Center for Nanoanalysis and Electron Microscopy (CENEM) Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)

Involved external institutions

Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung GmbH (HZG) DE Germany (DE)

How to cite

APA:

Wang, L., Zenk, C., Stark, A., Felfer, P., Gabrisch, H., Göken, M.,... Pyczak, F. (2017). Morphology evolution of Ti3AlC carbide precipitates in high Nb containing TiAl alloys. Acta Materialia, 137, 36-44. https://doi.org/10.1016/j.actamat.2017.07.018

MLA:

Wang, Li, et al. "Morphology evolution of Ti3AlC carbide precipitates in high Nb containing TiAl alloys." Acta Materialia 137 (2017): 36-44.

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