|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Coupled Effects of Shear and Temperature on Intermixing in Cu-Ni Multilayers
||Qin Pang, Jenna A. Bilbrey, Arun Devaraj, Suveen Mathaudhu, Peter V. Sushko
|On-Site Speaker (Planned)
Epitaxial films represent a convenient model for studies of initial stages of mechanically induced deformations. Here, we discuss atomic-scale pathways of shear-induced intermixing across epitaxial Cu-Ni heterojunction at finite temperatures. Using first principles simulations, we found that the orientation of shear vector with respect to the interface determines whether shear leads to intermixing between Cu and Ni or interface reorientation. The isolated vacancies were found to reduce the magnitude of the shear corresponding to the onset of plastic deformation, facilitating the intermixing process. There is a preferential vacancy diffusion across the interface from Ni into Cu, corresponding to the diffusion of Cu atoms into the Ni host. The energy barrier for this process (0.6 eV) decreases under applied shear by as much as 8.3 % for shear strain of 0.08 at 0K. This effect is enhanced at elevated temperature; spontaneous diffusion is observed at simulated temperature of 1000 K.
||Computational Materials Science & Engineering, Phase Transformations, Thin Films and Interfaces