|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Computational Design and Simulation of Materials (CDSM 2018): Atomistic Simulations
||Simulation of Solidification/Devitrification in Ni-Nb Alloys
||Mikhail Mendelev, Tongqi Wen, Cai-Zhuang Wang
|On-Site Speaker (Planned)
Ni-Nb is an interesting case of binary metallic alloys without stable stoichiometric compounds which nevertheless can form a bulk metallic glass (Ni62Nb38). The liquid/glass structure of this alloy has been intensively studied to explain this phenomenon. However, this approach ignores the obvious fact that glass will necessarily form if crystalline counterparts cannot form or grow. Therefore, we employed the classical molecular dynamics (MD) simulation to study the competing crystalline phase growth. A new semi-empirical potential was fitted to the pure element data, the alloy liquid structure obtained from the ab initio molecular dynamics simulation and the formation energies of the most important crystalline compounds. The MD simulation demonstrated that while the Ni3Nb phase shows rather fast growth from the liquid alloys, the growth of the Ni6Nb7 phase is extremely slow even when this phase is in contact with the liquid of the same composition which explains the good glass formability.
||Planned: Supplemental Proceedings volume