About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Characterization Techniques for Quantifying and Modeling Deformation
|
| Presentation Title |
In-Situ TEM Investigation of Fracture Growth in Novel Nanolaminate Thin Films |
| Author(s) |
Vivek Devulapalli, Tijmen Vermeij, Amit Sharma, Johann Michler, Xavier Maeder |
| On-Site Speaker (Planned) |
Vivek Devulapalli |
| Abstract Scope |
In-situ transmission electron microscopy reveals deformation mechanisms in Cu-Al multilayer thin films with ultrathin amorphous Al₂O₃ interlayers. The multilayer system comprised 30-120 nm Cu-10% Al layers separated by 2 nm Al₂O₃ interlayers deposited via atomic layer deposition. Using a correlative approach, we conducted micron-scale SEM testing to derive stress-strain data and correlated these findings with nanoscale TEM observations. Real-time TEM observations during tensile testing showed void nucleation preferentially at ALD/grain boundary interfaces, forcing tortuous crack paths that enhanced toughness. Multiple concurrent deformation mechanisms operated ahead of crack tips: dislocation glide, grain boundary sliding, detwinning, and grain rotation. Twin fraction decreased from 30% to 20% during crack growth. Remarkably, amorphous Al₂O₃ interlayers exhibited exceptional ductility, thinning from 2 nm to ~500 pm before failure. This unprecedented behavior in brittle ceramics, combined with complex crack propagation pathways, contributes to enhanced mechanical performance and provides crucial design insights for damage-tolerant metallic thin films. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, Thin Films and Interfaces, Mechanical Properties |