About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Interstitial–Metal Interactions: The Outsized Role of Small Atoms
|
| Presentation Title |
Hydrogen-Vacancy Co-Segregation and Fast Grain-Boundary Hydrogen Diffusion in Copper |
| Author(s) |
Vasileios Fotopoulos, Alexander L. Shluger |
| On-Site Speaker (Planned) |
Vasileios Fotopoulos |
| Abstract Scope |
Hydrogen embrittlement and voiding in copper remain important reliability concerns in structural components and electronic interconnects, yet the atomistic pathway linking hydrogen exposure to degradation remains unclear. Here, we combine density functional theory and bond-order potential simulations to connect H₂ exposure at Cu surfaces with hydrogen incorporation, diffusion, and H–Cu vacancy complex formation at grain boundaries. DFT calculations show that atomic hydrogen preferentially adsorbs at undercoordinated surface sites and incorporates more favorably at a Σ5 grain boundary than in bulk Cu. Hydrogen also stabilizes Cu vacancy segregation, producing H–Cu vacancy co-segregation energy gains of up to −0.8 eV. Large-cell simulations reveal continuous surface-to-grain-boundary and grain-boundary diffusion pathways, with barriers as low as 0.20 eV, compared with 0.42 eV in bulk Cu and 0.6 eV for surface-to-bulk penetration. These results identify grain boundaries as fast hydrogen transport pathways and sites for vacancy stabilization. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Modeling and Simulation, Copper / Nickel / Cobalt |