About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
|
Symposium
|
Computational Discovery, Understanding, and Design of Multi-principal Element Materials
|
Presentation Title |
Computational Studies of Deformation Twinning in BCC Complex Concentrated Alloys |
Author(s) |
Ganlin Chen, Amir Hassan Zahiri, Liang Qi |
On-Site Speaker (Planned) |
Liang Qi |
Abstract Scope |
Deformation twinning provides critical plastic deformation mechanisms to tune the strength and ductility of BCC Complex Concentrated Alloys (CCAs). However, physical mechanisms that determine the types/magnitudes of twinning in CCAs are still unclear due to the complex potential energy landscape related to plastic deformations and diffusionless phase transformations in CCAs. We applied computational studies to understand and tune the correlations between diffusionless phase transformations and deformation twinning in these CCAs at various compositions and temperatures. First-principles calculations were performed to study the structures and energy stability of different phases related to the twinning paths. We also applied atomistic simulations with classical interatomic potentials to further analyze the nucleation and growth mechanisms of twin embryos in both Ti-Nb binary alloys and Ti-Nb-Mo-Ta CCAs at finite temperatures. These atomistic simulation results combined with crystallographic theory can provide quantitative energetic criteria to select the twinning activities based on the phase stability of CCAs. |