Publication details
On the energetics of the cubic-to-hexagonal transformations in TiAl plus Mo alloys
| Authors | |
|---|---|
| Year of publication | 2022 |
| Type | Article in Periodical |
| Magazine / Source | Acta Materialia |
| MU Faculty or unit | |
| Citation | |
| Web | https://doi.org/10.1016/j.actamat.2022.118268 |
| Doi | http://dx.doi.org/10.1016/j.actamat.2022.118268 |
| Keywords | Density functional theory; TiAl; Martensitic transformations; Diffusionless transformations |
| Description | Diffusionless transformations allow access to metastable phases and enrich the materials design portfolio. They are well suited for atomistic modeling; nonetheless, they are challenging when involving disordered systems or alloys with complex compositions. This work presents a comprehensive study of transforma-tion energetics between bcc and hcp ordered and disordered phases in the TiAl+Mo model alloy system. By employing two complementary techniques I. VASP-SQS, and II. EMTO-CPA, we can show that chemical disorder flattens the energy landscape but may introduce a small barrier. Unlike that, the energetics of ordered phases are barrier-less and hence would suggest a spontaneous transformation. Finally, we show that Mo stabilizes the bcc phases, leading to a barrier-less transformation hcp -+ bcc for both ordered and disordered states when Mo content exceeds ti 12 at.%. |