TY  - JOUR
AU  - Wang, Li
AU  - Zenk, Carolin
AU  - Stark, Andreas
AU  - Felfer, Peter
AU  - Gabrisch, Heike
AU  - Göken, Mathias
AU  - Lorenz, Uwe
AU  - Pyczak, Florian
TI  - Morphology evolution of Ti<sub>3</sub>AlC carbide precipitates in high Nb containing TiAl alloys
JO  - Acta materialia
VL  - 137
SN  - 1359-6454
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - PUBDB-2017-14130
SP  - 36 - 44
PY  - 2017
AB  - This work elucidates the morphology evolution of perovskite Ti<sub>3</sub>AlC carbides in a Ti-45Al-5Nb-0.75C alloy during ageing at 800 °C. The carbides in the γ matrix are initially needle-shaped with their long axis parallel to the [001] lattice direction of the γ 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]γ 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.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000408596600004
DO  - DOI:10.1016/j.actamat.2017.07.018
UR  - https://bib-pubdb1.desy.de/record/398566
ER  -