Influence of excess volumes induced by Re and W on dislocation motion and creep in Ni-base single crystal superalloys
- A comprehensive 3D discrete dislocation dynamics model for Ni-base single crystal superalloys was used to investigate the influence of excess volumes induced by solute atoms Re and W on dislocation motion and creep under different tensile loads at 850 °C. The solute atoms were distributed homogeneously only in \(\gamma\) matrix channels. Their excess volumes due to the size difference from the host Ni were calculated by density functional theory. The excess volume affected dislocation glide more strongly than dislocation climb. The relative positions of dislocations and solute atoms determined the magnitude of back stresses on the dislocation motion. Without diffusion of solute atoms, it was found that W with a larger excess volume had a stronger strengthening effect than Re. With increasing concentration of solute atoms, the creep resistance increased. However, a low external stress reduced the influence of different excess volumes and different concentrations on creep.
| Author: | Siwen GaoORCiDGND, Zerong YangGND, Maximilian GrabowskiORCiDGND, Jutta RogalORCiDGND, Ralf DrautzORCiDGND, Alexander HartmaierORCiDGND |
|---|---|
| URN: | urn:nbn:de:hbz:294-71034 |
| DOI: | https://doi.org/10.3390/met9060637 |
| Parent Title (English): | Metals |
| Subtitle (English): | a 3D discrete dislocation dynamics study |
| Publisher: | MDPI |
| Place of publication: | Basel |
| Document Type: | Article |
| Language: | English |
| Date of Publication (online): | 2020/04/06 |
| Date of first Publication: | 2019/06/01 |
| Publishing Institution: | Ruhr-Universität Bochum, Universitätsbibliothek |
| Tag: | DFT; creep; dislocation dynamics; excess volume; solute atom; superalloy |
| Volume: | 9 |
| Issue: | 6, Article 637 |
| First Page: | 637-1 |
| Last Page: | 637-15 |
| Institutes/Facilities: | Interdisciplinary Centre for Advanced Materials Simulation (ICAMS), Department of micromechanical and macroscopic modelling |
| open_access (DINI-Set): | open_access |
| Licence (English): |  Creative Commons - CC BY 4.0 - Attribution 4.0 International |
