@inproceedings{KutzscheZhangAppeletal., author = {Kutzsche, Anja and Zhang, J. and Appel, Fritz and Leyens, Christoph and Viehweger, Bernd}, title = {Forging of Beta-Phase containing gamma-TiAl alloys}, language = {en} } @incollection{LindemannGlavatskikhLeyensetal., author = {Lindemann, Janny and Glavatskikh, Maria and Leyens, Christoph and Oehring, Michael and Appel, Fritz}, title = {Influence of Mechanical Surface Treatments on the High Cycle Fatigue Performance of Gamma Titanium Aluminides}, language = {en} } @misc{PaulOehringAppeletal., author = {Paul, Jonathan and Oehring, Michael and Appel, Fritz and Pyczak, Florian}, title = {Depth resolved near-surface residual stresses in γ-based TiAl before and after high-temperature exposure}, series = {Intermetallics}, volume = {84}, journal = {Intermetallics}, issn = {0966-9795}, pages = {103 -- 111}, language = {en} } @inproceedings{GlavatskikhLindemannLeyensetal., author = {Glavatskikh, Maria and Lindemann, Janny and Leyens, Christoph and Oehring, Michael and Appel, Fritz}, title = {Surface Strengthening for Enhanced Fatigue Performance of Gamma Titanium Aluminides}, series = {Structural aluminides for elevated temperatures, proceedings of the Structural Aluminides for Elevated Temperatures Symposium, held during TMS 2008 annual meeting \& exhibition, New Orleans, Louisiana, USA, March 9 - 13, 2008}, booktitle = {Structural aluminides for elevated temperatures, proceedings of the Structural Aluminides for Elevated Temperatures Symposium, held during TMS 2008 annual meeting \& exhibition, New Orleans, Louisiana, USA, March 9 - 13, 2008}, editor = {Kim, Young-Won}, publisher = {TMS}, address = {Warrendale, Pa.}, isbn = {978-0-87339-720-9}, pages = {111 -- 118}, language = {en} } @article{LindemannKutzscheOehringetal., author = {Lindemann, Janny and Kutzsche, Anja and Oehring, Michael and Appel, Fritz}, title = {Influence of Mechanical Surface Treatments on the Fatigue Performance of the Gamma TiAl Alloy Ti-45Al-9Nb-0.2C}, series = {Materials Science Forum}, volume = {539-543}, journal = {Materials Science Forum}, issn = {0255-5476}, pages = {1553 -- 1558}, language = {en} } @article{LindemannBuqueAppel, author = {Lindemann, Janny and Buque, Cesar and Appel, Fritz}, title = {Effect of Shot Peening on the Fatigue Performance of a Lamellar Titanium Aluminide Alloy}, language = {en} } @misc{PyczakAppelLimbergetal., author = {Pyczak, Florian and Appel, Fritz and Limberg, Wolfgang and Lorenz, Uwe and Oehring, Michael and Paul, Jonathan and Schimansky, Frank-Peter}, title = {Novel Processing Techniques for gamma-TiAl Alloys}, series = {Materials Science Forum}, journal = {Materials Science Forum}, number = {690}, issn = {1662-9752}, pages = {145 -- 148}, language = {en} } @misc{SongAppelPyczaketal., author = {Song, Lin and Appel, Fritz and Pyczak, Florian and Zhanbing, He and Junpin, Lin and Tiebang, Zhang}, title = {Characterization of primary, secondary and tertiary {202¯1}<1¯014> successive internal twins in the D019 ordered hexagonal α2-Ti3Al phase}, series = {Acta Materialia}, journal = {Acta Materialia}, number = {222}, issn = {1873-2453}, doi = {10.1016/j.actamat.2021.117391}, abstract = {Due to the lack of independent slip systems and the difficulty in mechanical twinning, D019 ordered α2-Ti3Al phase is known to be of substantial mechanical anisotropy, which partly accounts for the low ductility of two-phase (α2+γ) TiAl alloys. However, recent studies have shown that in Al-rich α2 phase compression deformation twins can be activated, which could be beneficial for the ductility of the alloys. In the present study, for the first time, we have revealed a novel internal twinning mechanism of α2 phase in a TiAl alloy deformed at high temperature. Three twin generations of a common type {202¯1}[removed] were revealed: Secondary twins formed within the primary twin, and tertiary twins formed in the secondary twin. It is important to note that this internal twin structure can only be observed in the [removed] direction but not the commonly used [removed] direction. The shear plane P of all twin variants is of type {12¯10}. Due to the variation of the twinning elements between the twin variants, the twinning shear is blunted. The interfaces between the twin variants are characterized by high-resolution electron microscopy. Special attention was paid to the structure of the coherent and incoherent twin boundaries. The effect of chemical ordering is discussed. Our results also shed light on the complex twinning mechanisms in hexagonal structures.}, language = {en} } @misc{SongAppelWangetal., author = {Song, Lin and Appel, Fritz and Wang, Li and Oehring, Michael and Hu, Xingguo and Stark, Andreas and He, Junyang and Lorenz, Uwe and Zhang, Tiebang and Lin, Junpin and Pyczak, Florian}, title = {New insights into high-temperature deformation and phase transformation mechanisms of lamellar structures in high Nb-containing TiAl alloys}, series = {Acta Materialia}, volume = {186}, journal = {Acta Materialia}, issn = {1873-2453}, doi = {10.1016/j.actamat.2020.01.021}, pages = {575 -- 586}, language = {en} } @misc{SongWangOehringetal., author = {Song, Lin and Wang, Li and Oehring, Michael and Hu, Xingguo and Appel, Fritz and Pyczak, Florian and Zhang, Tiebang}, title = {Evidence for deformation twinning of the D019-α2 phase in a high Nb containing TiAl alloy}, series = {Intermetallics}, volume = {109}, journal = {Intermetallics}, issn = {0966-9795}, doi = {10.1016/j.intermet.2019.03.014}, pages = {91 -- 96}, language = {en} } @misc{SongAppelLiuetal., author = {Song, Lin and Appel, Fritz and Liu, Wenhao and Pyczak, Florian and Zhang, Tiebang}, title = {{11¯01} tension twins and {11¯01}-{22¯01}/{22¯01}-{11¯01} double twins in the D019 ordered hexagonal α2-Ti3Al phase}, series = {Acta Materialia}, volume = {260}, journal = {Acta Materialia}, number = {3}, doi = {10.1016/j.actamat.2023.119335}, language = {en} }