Multi-Doping Effect on Ductility of TiAl3: A DFT Study
In this study, mechanical behaviors of D022–TiAl3 intermetallic compound co-doped by W–M (M = C, Ge, Pb, Si and Sn) were simulated using density functional theory. The calculated bulk modulus, shear modulus, Young’s modulus and Pugh’s ratio all confirm that the introduction of W–M co-dopants effectively increases ductility in D022–TiAl3. By detailed thermodynamic and electronic structure analysis, we revealed that W–M co-doped TiAl3 systems are mechanically and thermodynamically stable. Among all systems, the most ductile is realized by W–C co-doping. In addition, the further electronic structure calculations indicated that such high ductility might originate from the dopant-induced d-band shift and the resulting electron redistribution. We systematically investigated the doped TiAl3 systems from both mechanical and electronic points of view. This study may shed some lights on designing novel TiAl-based materials with enhanced ductility.
KeywordsMulti-doped TiAl3 Ductility Elastic properties First-principles calculations Electronic structure
This work was supported by the A*STAR Computational Resource Centre through the use of its high-performance computing facilities.
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