| About this Abstract |
| Meeting |
Materials Science & Technology 2011
|
| Symposium
|
Phase Stability, Diffusion, Kinetics and their Applications (PSDK-VI)
|
| Presentation Title |
Molecular Dynamics Simulations of Reaction, Diffusion and Segregation in Nanoscale Equiatomic Ni-Al Systems |
| Author(s) |
Irina V Belova, Alexander V Evteev, Elena V Levchenko, Graeme E. Murch |
| On-Site Speaker (Planned) |
Irina V Belova |
| Abstract Scope |
Using long-time molecular dynamics simulations in combination with one of the most reliable embedded-atom method potentials, we analyze the alloying reaction in Ni–Al core-shell nanoparticles as well as diffusion and segregation in B2-NiAl and liquid Ni50-Al50 phases. We show the ability to control the self-heating rate and alloying pathways of the reaction in Ni–Al core-shell nanoparticles. We demonstrate that near the stoichiometric composition of B2-NiAl isolated Ni vacancies strongly dominate in concentration over all of their bound complexes with Ni antisites. It suggests that near the stoichiometric composition isolated Ni vacancies play the key role in atomic diffusion for both Ni and Al atoms. We show that Al segregation to the surface takes place in both B2-NiAl and liquid Ni50Al50 phases. It is estimated that near the melting temperature Ni atoms diffuse on average 1.2 and 2.5 times faster than Al atoms in liquid Ni50Al50 and B2-NiAl phases, respectively. |
| Proceedings Inclusion? |
Definite: A CD-only volume |