|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Ultrafine-grained Materials X
||Crystal Plasticity of Microstructural Evolution via Twin Boundary Migration in Nanotwinned Metals
||Shailendra P. Joshi, Kartikey Joshi
|On-Site Speaker (Planned)
||Shailendra P. Joshi
We investigate microstructure evolution in nanotwinned metals (NTM) using our 3D crystal plasticity materials that include size-dependent TB migration and strengthening effects. Yield strengthening and back stress effects are modeled via gradients of slip rate and slip while TB migration is explicitly modeled by incorporating twinning partial slip systems and dislocation-TB interactions leading to interfacial yielding. Detailed finite element calculations reveal intimate coupling between the material strengthening and TB migration induced softening as a function of twin size and loading orientation.
We propose an expression that maps TB migration speed to relevant material parameters. Using this expression, we perform numerical simulations of polycrystalline microstructures to predict microstructural evolution via TB migration. Results from polycrystalline simulations are compared with experimental results.
Finally, we present preliminary results on the role of TB migration in mediating ductile failure mechanisms in NT materials.
||Planned: Supplemental Proceedings volume