@misc{CaoWangTaoetal., author = {Cao, Xianli and Wang, Li and Tao, Hui and He, Weiwei and Liang, Xiaopeng and Liu, Bin and Oehring, Michael and Paul, Jonathan and Pyczak, Florian and Liu, Yong}, title = {Morphology evolution of P-Ti3AlC carbides and their influence on creep properties in a crept Ti-45Al-5Nb-0.75C alloy}, series = {Journal of Materials Research and Technology}, volume = {29}, journal = {Journal of Materials Research and Technology}, publisher = {Elsevier BV}, issn = {2238-7854}, doi = {10.1016/j.jmrt.2024.02.146}, pages = {4181 -- 4190}, language = {en} } @misc{WangWangLiangetal., author = {Wang, Li and Wang, Yihao and Liang, Xiaopeng and Liu, Bin and He, Junyang and Oehring, Michael and Pyczak, Florian and Liu, Yong}, title = {Revealing the unique evolution and splitting behavior of carbides at atomic-scale in TiAl alloys : the role of elastic interactions and chemical fluctuations}, series = {Acta materialia}, volume = {296}, journal = {Acta materialia}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {1359-6454}, doi = {10.1016/j.actamat.2025.121277}, pages = {1 -- 17}, abstract = {Cubic perovskite-Ti3AlC carbides are essential strengthening particles in TiAl alloys, especially for application above 800 °C where coarsening is expected to occur. However, these carbides can decompose into small sub-particles upon extended annealing, and the underlying atomic-scale mechanisms, especially structural and compositional changes, driving this unique splitting remain unclear. This study revisits this behavior in a Ti-45Al-5Nb-0.75C alloy utilizing probe-corrected transmission electron microscopy, atom probe tomography and first-principle calculations. The results reveal that the elastic interactions significantly influence carbide evolution. While needle-like carbides transform to intact plates during aging, those in high-density regions tend to coalesce or align along elastically softest γ-matrix directions, forming low-energy plate-like carbide conglomerates. With extended annealing, periodic chemical fluctuations driven by lattice misfit, especially along the needles induce splitting. Simultaneously, a γi-phase with a larger tetragonality and a 90°-rotated c-axis relative to the γ matrix emerges between the sub-particles, which exhibits near-zero lattice mismatch with carbides along [001], combined with mass-center shifts of carbides, further stabilizing the split configurations. This study provides atomic-scale insights into the evolution and stability of strengthening precipitates in systems with tetragonal misfit, and offers new strategies for improving creep properties of TiAl alloys by tailoring carbide configurations.}, language = {en} }