About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Nanostructured Materials in Extreme Environments
|
Presentation Title |
Nanotwin Stability under Temperature-dependent Deformation States |
Author(s) |
Jarod Robinson, Akarsh Verma, Eric Homer, Gregory B. Thompson |
On-Site Speaker (Planned) |
Jarod Robinson |
Abstract Scope |
Nanotwins can provide significant strengthening; however, these same boundaries can also de-twin facilitating a loss of strength. This de-twinning behavior can become more prevalent at cryogenic temperatures. In this work, a series of copper nanotwinned columnar grains have been alloyed with aluminum. These alloys have been subjected to deformation at approximately -190°C and ambient temperature. Under indentation, at a lower aluminum solute content (2at.%), the columnar grains bent and corresponded with a loss of twins. In contrast, at a higher aluminum solute content (8at.%) the grains sheared and retained the high density of twins. Molecular dynamics based atomistic simulations reveal an increase in the incoherent twin boundary velocity with decreasing temperature (Non-Arrhenius behavior), but this boundary velocity is reduced and becomes more invariant with temperature as the solute content increases. Coupling increases in solid solution strengthening and nanotwin stabilization is used to explain the microstructural differences between the alloys. |
Proceedings Inclusion? |
Planned: |
Keywords |
Copper / Nickel / Cobalt, Modeling and Simulation, |