| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Development in Light Weight Alloys and Composites
|
| Presentation Title |
Solute Synergy Improved Thermal Stability of Nanotwinned Al Alloys |
| Author(s) |
Nicholas A. Richter, Yifan Zhang, Mingyu Gong, Tongjun Niu, Bo Yang, Sichuang Xue, Jian Wang, Xinghang Zhang |
| On-Site Speaker (Planned) |
Nicholas A. Richter |
| Abstract Scope |
Nanocrystalline Aluminum (Al) alloys have various engineering applications. However, they often suffer from poor thermal stability due to the large driving force for grain coarsening. In this study, we implement a strategy of solute synergy to simultaneously bolster mechanical strength and thermal stability. Using in-situ micropillar compression testing, it is shown that Zr additions can largely improve the flow stress of nanotwinned Al-Co alloys to 1.3 GPa, while maintaining significant deformability. Zr solutes also promote microstructural and mechanical stability even when annealing up to 400 °C (0.72Tm of Al). Density functional theory calculations uncover the role of Co-Zr solute pairs in pinning and stabilizing incoherent twin boundaries. This work highlights the possibilities for improvement of mechanical strength and thermal stability of nanocrystalline Al alloys when combining solute pairs that possess these synergistic effect. |