TY  - JOUR
AU  - Wang, Li
AU  - Oehring, Michael
AU  - Lorenz, Uwe
AU  - Stark, Andreas
AU  - Pyczak, Florian
TI  - New insights into perovskite-Ti<sub>3</sub>AlC precipitate splitting in a Ti-45Al-5Nb-0.75C alloy by transmission electron microscopy
JO  - Intermetallics
VL  - 100
SN  - 0966-9795
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - PUBDB-2018-03646
SP  - 70 - 76
PY  - 2018
N1  - © Elsevier B.V.
AB  - The addition of carbon in TiAl alloys can improve the mechanical properties by precipitate hardening through the perovskite Ti<sub>3</sub>AlC carbide. Usually precipitates coarsen during continuous annealing. However, in the Ti-45Al-5Nb-0.75C alloy a splitting of the perovskite carbides was observed in later stages of annealing. By investigation with transmission electron microscopy the details of this splitting process are revealed after annealing at 900 °C. The results show that the re-orientation of the γ phase regions between sub-particles is associated with the splitting step from carbide needles into small sub-particles. γ domains with a different orientation with respect to the γ matrix nucleate and gradually replace the γ matrix phase in regions between the carbide sub-particles. The progress of the splitting process is locally different in different carbides and also in one individual carbide. By increasing the temperature from 800 to 900 °C the growth of the emerging carbide conglomerates and the splitting process of the carbides are greatly accelerated. It is found that both are diffusion-controlled processes.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000440119100010
DO  - DOI:10.1016/j.intermet.2018.06.006
UR  - https://bib-pubdb1.desy.de/record/410498
ER  -