[Zurück]

V. Moraes, H. Riedl, C. Fuger, P. Polcik, H. Bolvardi, D. Holec, P.H. Mayrhofer:
"Ab initio inspired design of ternary boride thin films";
Scientific Reports, 8 (2018), 9288; S. 1 - 9.

The demand to discover new materials is scientifcally as well as industrially a continuously present topic, covering all diferent felds of application. The recent scientifc work on thin flm materials has shown, that especially for nitride-based protective coatings, computationally-driven understanding and
modelling serves as a reliable trend-giver and can be used for target-oriented experiments. In this study, semi-automated density functional theory (DFT) calculations were used, to sweep across transition metal diborides in order to characterize their
structure, phase stability and mechanical properties. We
show that early transition metal diborides (TiB2, VB2, etc.) tend to be chemically more stable in the AlB2
structure type, whereas late transition metal diborides (WB2, ReB2, etc.) are preferably stabilized in the
W2B5−x structure type. Closely related, we could prove that point defects such as vacancies signifcantly
infuence the phase stability and even can reverse the preference for the AlB2 or W2B5−x structure.
Furthermore, investigations on the brittle-ductile behavior of the various diborides reveal, that the
metastable structures are more ductile than their stable counterparts (WB2, TcB2, etc.). To design thin
flm materials, e.g. ternary or layered systems, this study is important for application oriented coating
development to focus experimental studies on the most perspective systems.

ab initio, ternary diborides

http://dx.doi.org/10.1038/s41598-018-27426-w

https://publik.tuwien.ac.at/files/publik_274322