| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Grain Boundaries, Interfaces, and Surfaces: Fundamental Structure-Property-Performance Relationships
|
| Presentation Title |
The Role of Grain Boundaries in Nucleation-controlled Plasticity of Metal Nanoparticles |
| Author(s) |
Eugen Rabkin, Amit Sharma, Jonathan Amodeo, Tatyana Fedyaev, Anuj Bisht, Olivier Thomas |
| On-Site Speaker (Planned) |
Eugen Rabkin |
| Abstract Scope |
We demonstrated that coating single crystalline Ag nanoparticles with a thin polycrystalline Au layer leads to mechanical weakening of the particles. Moreover, while the single crystalline Ag nanoparticles yield in a single large displacement burst when loaded in compression, their Ag-Au core-shell counterparts demonstrate a more homogeneous deformation with signs of strain hardening. On the contrary, twinned nanoparticles of the homogeneous Ag-Au alloys yield in a similar manner and at a comparable stress as single crystalline Ag particles. Our molecular dynamics simulations demonstrate that weakening of the core-shell particles at low strains is attributed to the dislocation nucleation at the random grain boundaries in the polycrystalline Au shell, and at the Ag-Au interphase boundary. Coherent twin boundaries are not as efficient as random ones in nucleation of new dislocations. |