| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advancing Current and State-of-the-Art Application of Ni- and Co-based Superalloys
|
| Presentation Title |
Numerical Calculation of Antiphase Boundary Energy of Ni-superalloys |
| Author(s) |
Mohammad Dodaran, Ali Hemmasian Ettefagh, Shengmin Guo, Shuai Shao |
| On-Site Speaker (Planned) |
Mohammad Dodaran |
| Abstract Scope |
Energetics of planar defects, such as antiphase boundary (APB), in the γ’ precipitates strongly affects tensile and fatigue properties in γ-γ’Ni-superalloys. For monotonic strength, APB energy represents the resistance of precipitates to slip. For fatigue, APB energy is closely related to the cross-slip tendency of superscrew dislocations. Cross-slip induces irreversible cyclic plastic deformation and, therefore, accumulation of fatigue damage. In this study, the effect of composition on APB energy is explored using cluster expansion (CE) method combining density function theory (DFT) calculations and Monte Carlo (MC) sampling. DFT calculations were performed by Quantum Espresso package to obtain energies of symmetrically inequivalent family of clusters providing input for CE. CE extracts the interaction among different alloying elements and calculates energy of atomistic structures with chemical disordering introduced by MC technique. APB energy, as a function of composition, is finally calculated by comparing the energies of structures with and without APBs. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |