| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Mechanical Behavior Related to Interface Physics IV
|
| Presentation Title |
Partially Active Grain-Boundary Segregation and Maximum Tensile Strengths in Nanocrystalline Silver-Copper Alloys |
| Author(s) |
Pavel Nikitin, Frederic Sansoz |
| On-Site Speaker (Planned) |
Pavel Nikitin |
| Abstract Scope |
Enhancement of strength in nanocrystalline alloys through grain-boundary (GB) segregation is a common but still challenging approach, because our understanding of segregation-induced interface strengthening mechanisms remains limited. Additionally, atomistic simulations could elucidate these mechanisms, yet their accuracy heavily relies on interatomic potentials, necessitating experimental validation. In this talk, we present a detailed study combining large-scale hybrid Monte-Carlo and Molecular Dynamics simulations, STEM analysis, and micromechanical tensile experiments to elucidate the effects of heterogeneous GB segregation on strength and failure behavior in nanocrystalline Ag-Cu alloys synthesized by co-sputtering with different Cu solute concentrations. Our findings delineate three concentration-dependent plasticity regimes: (1) dilute GB solute strengthening at low concentrations, (2) shear-band softening at high concentrations, and (3) an extended plateau of maximum tensile strengths for intermediate concentrations. Direct STEM observations reveal non-uniform Cu segregation across different interfaces. A mechanistic model of interface strengthening by partially active GB segregation mechanism is proposed. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, Thin Films and Interfaces, Nanotechnology |