Abstract
Nanotwinned metals have demonstrated the capacity for concomitant high strength and ductility. However, metals with high stacking fault energies, such as aluminum (Al), have a low propensity for twin formation. Here, we show the fabrication of supersaturated solid-solution Al-Zr alloys with a high density of growth twins. Incoherent twin boundaries (ITBs) are strong barriers to dislocation motion, while mobile partial dislocations promote plasticity. These deformable nanotwinned Al-Zr alloys reach a flow stress of ∼1 GPa, as demonstrated using in situ micropillar compression tests. Density functional theory calculations uncover the role Zr solute plays in the formation and deformation of the nanotwinned microstructure. This study features a strategy for incorporating ITBs and 9R phase into Al alloys for simultaneous benefits to strength and deformability.
| Original language | English |
|---|---|
| Article number | 065104 |
| Journal | Journal of Applied Physics |
| Volume | 132 |
| Issue number | 6 |
| DOIs | |
| State | Published - Aug 14 2022 |
| Externally published | Yes |
Funding
This project is primarily funded by DoE-BES (Basic Energy Sciences) under Grant No. DE-SC0016337. The ASTAR crystal orientation system in TEM microscope is supported by ONR-DURIP under Award No. N00014-17-1-2921. Access to the Microscopy Facilities at Purdue University and Center for Integrated Nanotechnologies (managed by Los Alamos National Laboratory) is also acknowledged. Atomistic simulations were completed utilizing the Holland Computing Center of the University of Nebraska, which receives support from the Nebraska Research Initiative.