About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Deformation and Transitions at Grain Boundaries VII
|
Presentation Title |
Predictions of Grain Boundary Segregation in bcc Refractory Metals based on Electronic Descriptors |
Author(s) |
Yong-Jie Hu, Ge Zhao, Baiyu Zhang, Chaoming Yang, Xiaofeng Qian, Liang Qi |
On-Site Speaker (Planned) |
Yong-Jie Hu |
Abstract Scope |
We discovered a universal correlation between two electronic descriptors and the solute-defect interaction energies in binary alloys of bcc refractory metals with transition-metal substitutional solutes. One electronic descriptor is the bimodality of the d-orbital local density of states for a matrix atom at the substitutional site, and the other is related to the hybridization strength between the valance sp- and d-bands for the same matrix atom. To test the predictive capabilities of the correlation model, substantial first-principles calculations were performed to calculate the solute segregation energies at complex high-index grain boundary (GB) structures in W and Ta. By comparing with direct first-principles calculations, our model shows excellent performance on the predictions of segregation energies and the overall temperature-dependent GB segregation concentrations for different matrix-solute element pairs. This newly discovered correlation model could be used as a screening tool to study the solute segregation in grain boundaries and other crystalline defects. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |